• Restorative Dentistry and Endodontics
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• v.9 no.1
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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).

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.11
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• pp.69-76
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• 2010

From the present paper we researched about the design of 4-Way Wilkinson divider with waveguide to stripline transition which used to split the LO signal with equi-amplitude and equi-phase in the X-Band Monopulse radar RF front-end. The monopulse radar front end operating in the X-Band is composed of 3 waveguide reception mixers which down convert sum, azimuth and elevation signal to IF and one SSB waveguide mixers which generate X-Band test signal. It is required the 4-way divider with low loss, equi amplitude and equiphase splitting the LO signal to provide the LO signal to each mixer consisting RF frontend. In this paper we designed and fabricated the 4-Way Wilkinson divider with waveguide transition to divide the LO signal into equi-amplitude and equi-phase. The fabricated Wilkinson divider have the insertion loss 6.8dB, VSWR 1.06~1.28, and phase balance maximum 4.5degree for each output ports.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.7
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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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.517-522
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• 2013

Small size ice-cream maker has two evaporators having different evaporating temperatures of $4^{\circ}C$ and $-8^{\circ}C$. In such case, ice-cream maker system design becomes complicated because multiple capillary tubes affects one another. In this study, performance analysis was conducted for the soft ice-cream maker having two evaporators operating at different temperatures. The compressor was analyzed using efficiency models, the capillary tube was modeled assuming one-dimensional flow, the condenser and the evaporators were modeld based on UA-LMTD method. The refrigeration cycle simulation program was developed applying the enthalpy, pressure and mass balance on each component. Comparison of the test data with the simulated results for R404A revealed that evaporator temperatures of refrigerator and freezer agreed within $3^{\circ}C$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.326-333
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• 2020

This study focused on self-effects and spouse-effects that impact marital satisfaction in sex role stereotypes, work-family conflict and work-family enrichment. 95 double-income couples participated in this study, and the paired T-Test and multiple regression analysis were conducted. The result of the study showed that sex role stereotypes, work-family conflict, and work-family enrichment are not significant differences in husband and wife, but a husbands was significantly higher than wife in marital satisfaction. In the next step, we considered variables affecting marital satisfaction, and found a significant difference between husband and wife. Work-family enrichment positively affected the husband's marital satisfaction, while the wife's satisfaction was positively affected by the husband's sex role stereotype and negatively affected by her work-family conflict. This study suggests that marriage enrichment programs, the education of husband and wife, and couple counseling should consider individual effects and spouse effects.

• Journal of the Korean Society of Physical Medicine
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• v.14 no.4
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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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• 2009.06a
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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.

• Journal of Korean Physical Therapy Science
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• v.26 no.3
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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.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.3
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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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• v.15 no.3
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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.