• 한국식품조리과학회지
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• 제16권2호
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• pp.99-111
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• 2000

The purpose of this study was to assess the qualities of cook/chilled soy sauce-glazed soybean curd with various packaging conditions as a trial to develop health-oriented convenience foods. The effects of three packaging methods, linear low density-polyethylene (LLD-PE), top sealing, and modified atmosphere packaging(MAP) on the shelf-life of HACCP-based cook/chilled soy sauce-glazed soybean curd were evaluated during 20 days of chilled storage in terms of time-temperature, microbiological (total aerobic plate count, psychrotrophic plate count, coliform, and fecal coliform count), chemical(pH and peroxide value(POV)), and sensory evaluation. The results of microbiological and chemical analyses were within the limits of the microbial and chemical standards for all phases after cooking. No significant differences were detected in microbial counts of the samples for all three packaging methods. However, sensory evaluation indicated that the top sealing and MAP methods showed a longer shelf-life than LLD-PE packaging. Recommended shelf-life of the product was 12 days for LLD-PE packaging, and 16 days for both top sealing and MAP. In conclusion, MAP was considered as the most effective packaging method for assuring microbial and sensory quality of this cook/chilled product.

• 한국화재소방학회논문지
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• 제18권4호
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• pp.93-102
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• 2004

원자력발전소에서 방화벽 관통부 내화충전구조는 화재가 발생장소 이외의 구역으로 전파되는 것을 차단하여 타구역에 설치된 안전에 중요한 기기를 보호하는 중요한 구성요소이다. 그러나 국내 장기 가동중 원전의 경우 관통부 충전구조의 내화성능을 입증하는 인증시험서가 구비되어 있지 않아 별도의 내화성능평가가 이루어져야 하고, 성능평가 결과가 적정 내화등급을 만족하지 못하는 관통부에 대해서는 관통물질의 재배치 둥의 구조변경이 이루어져야 한다 본 연구는 분석적인 방법에 의한 관통부 충전구조의 내화성능 평가기법을 정립하고. 분석적인 방법을 적용하여 실제 발전소에 설치된 관통부 충전구조의 내화등급을 결정하는 방법을 제시하였다. 이를 통하여 분석에 의한 관통부 충전구조의 내화성능평가방법은 내화인증시험서가 없는 국내 장기가동 원자력발전소에 효율적으로 적용될 수 있을 것으로 판단된다.

• Transactions on Electrical and Electronic Materials
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• 제8권6호
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• pp.255-259
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• 2007

We have synthesized $CaS:Eu^{2+}$ phosphor by using a sealing vessel and evaluated its photoluminescence properties. The method using a sealing vessel is simple and economical in comparison with other methods reported up to date. As an activator concentration was increased from 0.1 mol% to 4 mol%, the main emission wavelength of the phosphor was increased from 642 nm to 651 nm due to the crystal field splitting of 5d levels of $Eu^{2+}$ ion. Although the same amount of $Eu_2O_3$ was used, the concentration of the activator ions, which were reduced from $Eu^{3+}\;to\;Eu^{2+}$ and substituted $Ca^{2+}$ ions, was increased with increase of firing temperature. Therefore, the main emission wavelength was also. shifted from 645 nm to 651 nm with increase of firing temperature from $1100^{\circ}C\;to\;1300^{\circ}C$. The critical distance($R_{c1}=20.65\;{\AA}$) between $Eu^{2+}$ ions calculated from the critical concentration was well matched with that($R_{c2}=19.17\;{\AA}$) calculated from the Dexter formula.

• 대한치과보철학회지
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• 제35권4호
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• pp.767-780
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• 1997

One of the most common problems of implant prosthesis is the screw loosening of abutment screws. This brings on discomfort in mastication, inflammation in the peri-implant tissue due to poor oral hygiene and fracture of prosthesis or loss of osseointegration. To prevent screw loosening, appropriate implantation to direct the occlusal force to the long axis of the implant, accurate design of the superstructure, decrease of the occlusal table, and adequate torque on the abutment screw are necessary. In this study the screw loosening torque was evaluated in implants with dimples or flutes in the internal surface of abutment screw holes. The abutments were fastened with slot type and hexagonal type abutment screws and were sealed with vinyl poly siloxane impression and bite registration material respectively. The screw loosening torque was evaluated after 1,800 and 12,600 times loading under a loading machine. The results were as follows. 1. The flute form group showed significantly higher loosening torque compared to the dimple form group and the group with no inner surface treatment (p<0.05). 2. There was no statistical difference in loosening torque according to the sealing materials. 3. The loosening torque according to the types of abutment screw showed no significant difference. 4. The loosening torque was significantly higher after 1800 times loading compared to 12600 times loading(p<0.05). From the above results. it is thought that formation of a flute in the internal surface of the screw hole decreases the chance of screw loosening, but the sealing materials and types of abutment screw did not show significant difference in prevention of screw loosening.

• 한국생산제조학회지
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• 제18권4호
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• pp.436-441
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• 2009

An air filter is a device to remove dust from the air supplied to the automotive engine. A requirement for the optimum air filter is to improve the capability to remove particles from the air it takes in, that is the efficiency and amount of dust collection. By removing dust from the air, the air filter prevents the engine cylinder from wear, reduces ventilation resistance, and thus improves engine output and guarantees intake performance. In order to guarantee such air filter performance, it is very important to properly seal the air filter. For passenger cars made in Korea, the air filters are fabricated with steel caps as their frames are large and their engine capacity is big. Recently however, European countries and Japan started using urethane for manufacturing the air filter, so that all foreign-made cars now have urethane filters. The urethanes used for air filters are applied in two ways: One is to use soft urethane for both top and bottom of the air filter and the other is to use soft urethane for the top and hard urethane for the bottom. Each of these method has unique problems. In this study, hard urethane is used for both top and bottom of the filter in order to improve those problems and increase the sealing efficiency. Especially for the top, NBR (rubber mold) is pre-settled in tough urethane and then the urethane is solidified through foaming, which makes it possible to develop a solid and double-sealed filter.

• Elastomers and Composites
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• 제53권4호
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• pp.213-219
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• 2018

The degradation mechanism and physical properties of an FKM O-ring were observed with thermal aging in this experiment. From X-ray photoelectron spectroscopy (XPS) analysis, we could observe carbon (285 eV), fluoro (688 eV), and oxygen (531 eV) peaks. Before thermal aging, the concentration of fluoro atoms was 51.23%, which decreased to 8.29% after thermal aging. The concentration of oxygen atoms increased from 3.16% to 20.39%. Under thermal aging, the FKM O-ring exhibited debonding of the fluoro-bond by oxidation. Analysis of the C1s, O1s, and F1s peaks revealed that the degradation reaction usually occurred at the C-F, C-F2, and C-F3 bonds, and generated a carboxyl group (-COOH) by oxidation. Due to the debonding reaction and decreasing mobility, the glass transition temperature of the FKM O-ring increased from $-15.91^{\circ}C$ to $-13.79^{\circ}C$. From the intermittent CSR test, the initial sealing force was 2,149.6 N, which decreased to 1,156.2 N after thermal aging. Thus, under thermal aging, the sealing force decreased to 46.2%, compared with its initial state. This phenomenon was caused by the debonding reaction and decreasing mobility of the FKM O-ring. The S-S curve exhibited a 50% increase in modulus, with break at a low strain and stress state. This was also attributed to the decreasing mobility due to thermal aging degradation.

• Restorative Dentistry and Endodontics
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• 제44권4호
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• pp.38.1-38.8
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• 2019

Navigation of the main root canal and dealing with a dens invaginatus (DI) is a challenging task in clinical practice. Recently, the guided endodontics technique has become an alternative method for accessing root canals, surgical cavities, and calcified root canals without causing iatrogenic damage to tissue. In this case report, the use of the guided endodontics technique for two maxillary lateral incisors with multiple DIs is described. A 16-year-old female patient was referred with the chief complaint of pain and discoloured upper front teeth. Based on clinical and radiographic findings, a diagnosis of pulp necrosis and chronic periapical abscess associated with double DI (Oehler's type II) was established for the upper left lateral maxillary incisor (tooth #22). Root canal treatment and the sealing of double DI with mineral trioxide aggregate was planned for tooth #22. For tooth #12 (Oehler's type II), preventive sealing of the DI was planned. Minimally invasive access to the double DI and the main root canal of tooth #22, and to the DI of tooth #12, was achieved using the guided endodontics technique. This technique can be a valuable tool because it reduces chair-time and, more importantly, the risk of iatrogenic damage to the tooth structure.

• 한국IT서비스학회지
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• 제17권3호
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• pp.53-61
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• 2018

In this paper, we propose a car sealing monitoring system combined with ICT Technology. The automobile sealer is an adhesive used to bond inner and outer panels of doors, hoods and trunks of an automobile body. The proposed car sealer monitoring system is a system that can accurately and automatically inspect the condition of the automobile sealer coating process in the general often factory production line where the lighting change is very severe. The sealer inspection module checks the state of the applied sealer using an area scan camera. The vision inspection algorithm is adaptive to various lighting environments to determine whether the sealer is defective or not. The captured images and test results are configured to send the task results to the task manager in real-time as a smartphone app. Vision inspection algorithms in the plant outdoors are very vulnerable to time-varying external light sources and by configuring a monitoring system based on smart mobile equipment, it is possible to perform production monitoring regardless of time and place. The applicability of this method was verified by applying it to an actual automotive sealer application process.

• Restorative Dentistry and Endodontics
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• 제13권1호
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• pp.113-120
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• 1988

The purpose of this study was to evaluate and compare the sealing ability of ZOE, FR and AH-26. Seventy two upper and lower anterior and premolor teeth were randomly selected and instrumented in a conventional method with K-file. After instrumentation and dry the canal, the teeth were divided into 3 groups and twenty four teeth in each group were filled with ZOE, FR, and AH-26 respectively. All the specimens were immersed into Indian Ink and decalcified in nitric acid and cleared in methyl salicylate. The apical leakage was evaluated by measuring the degree of ink penetration with caliper at the intervals of 1 day, 7 days and 14 days. The results were as follows; 1. In AH-26 and FR groups, there was increase in penetration related to increased time of immersion in the ink. 2. FR group showed the least penetration in 3 groups. 3. Statistics showed that there was no significant difference among the each sealer groups.

• 조명전기설비학회논문지
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• 제23권5호
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• pp.29-35
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• 2009

FED는 잠재적인 평판기술에 따라 현재 연구되고 있다. 이 논문의 제안은 FED 핵심적인 개발을 위한 진공 패키징 기술에 대한 연구결과를 보여준다. FED 진공 패키징을 위해서는 유리/유리 접합, 진공배기, 게터기술, 그리고 시뮬레이션, 진공패키징 기술을 연구하였다. 유리/유리 접합은 프릿 글래스를 사용하므로 형태에 따르고, 내부 압력은 $2{\times}10^{-5}$[Torr]이며 패널로서 완성을 보여준다. 게터의 결과에 따라 그것은 압력의 증가는 박막 게터에 의해 불순기체가 줄어드는 것을 보여주었다.