• The Journal of Korean Academy of Prosthodontics
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• v.47 no.1
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• pp.29-38
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• 2009

Statement of problem: A casting connection technique is widely used for repair, correction and addition to base metal framework. However, a casting connection technique may increase the risk of failure in clinical situations when high stresses exist. Purpose: The purpose of this study was to investigate the mechanical retentive groove design comparatively to increase the joint strength by using the three-dimensional finite element analysis model of a 3-unit fixed partial denture. Material and methods: Ten finite element models were constructed. (Model A: One retentive groove, Model B: Two retentive grooves, Model C: Three retentive grooves, Model D: Four retentive grooves, Model E: One horizontal groove and two vertical grooves, Model F: Two horizontal grooves and one vertical groove, Model G: One groove with the enlarged dimension, Model H: Two grooves with the enlarged dimension, Model I: One groove with the increased height, Model J: One groove with the increased width of base). The vertical force was applied to the mesial and the distal fossa to the casting connection of mandibular first molar. Results: The main factors, affecting joint strength of casting connection were both the retention between the primary cast and the secondary cast and the thickness of the primary cast remaining after preparing retentive groove. The increase of retentive force, according to the numbers and the dimension of retentive groove had an effect on distributing stress. However, in some cases, the increase of retentive force resulted in the increase of stress by reducing thickness of the primary cast in the connection area. Conclusion: The design of retentive groove that limits number of retentive groove for metal thickness and increases the depth of retentive groove for retention is highly recommended.

• 한국정보통신설비학회:학술대회논문집
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• 2009.08a
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• pp.40-44
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• 2009

지하구는 도시의 신경망이라 할 수 있는 통신, 전력, 상수도, 난방, 쓰레기 처리시설 등 도시 운용/관리를 위한 주요시설물을 안전하게 수용하고, 유지 관리하기 위한 시설로 IT기술을 이용하여 수용된 시설을 효과적으로 유지/관리하고, 재난으로부터 안전하게 보호함과 동시에 최소의 비용과 에너지로 수용된 시설물을 유지관리하기 위한 연구가 많이 진행되고 있다. 따라서 본 논문에서는 지하구(공동구, 통신구, 전력구)의 운용 및 유지관리와 지하구에서 발생될 수 있는 각종 재난에 대응하기 위한 지하구 운용 및 유지관리에 대해 알아보고, 지하구 내부에 수용된 시설물을 효과적으로 유지관리하고 재난에 신속히 대응하기 위한 지하구 환경모니터링 시스템에 대해 기술 하고자 한다. 지하구 환경모니터링 시스템은 지하구 내부에는 전력, 상수도, 통신, 난방 등 다양한 시설물이 수용되어 있으며, 이러한 시설물의 부식, 고장 등으로부터 보호하기 위해 지하구내부의 환기시스템의 송풍기와 지하수와 기상재해로 인한 지하구 및 수용시설물의 침수를 막기 위한 양수펌프에 대해 실시간 상태모니터링 통해 송풍기 및 펌프의 고장여부를 판단하여 관리자에게 알림으로써 관리자가 신속하게 대응 할 수 있도록 하였다. 송풍기의 제어는 지하의 내부와 외부에 설치된 온/습도 센서를 통해 지하구 내부환경을 최적으로 유지할 수 있도록 함으로써 쾌적한 지하 내부환경 유지하고, 급/배기가 필요할 경우에만 송풍기를 가동함으로써 에너지를 절약 할 수 있으며, 화재, 침수 등에 대한 재난시 환풍기의 급/배기, 정지 등을 신속하게 제어할 수 있도록 하였다. 또한 지하구내부에서 발생된 재난을 유/무선을 이용하여 신속하게 지하구 주변의 장치(U-Pole 또는 통합컨트롤러)를 통해 경보를 전파함으로써 주변 시민들이 안전하게 대피할 수 있도록 하였다. 그리고 지하구 환경모니터링 시스템을 검증하기 위해 실제 지하구 및 실험실에 시스템 및 Test Board을 설치하여 운용시험을 실시 하였다.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.4 no.2
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• pp.18-23
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• 1998

Weight loss of cucumber packed with corrugated paperboard box after 7 days storage at 20oC was 4.9%, and those of 20LD, 40LD film and EPS box were 0.8, 0.7, and 0.8%. Total ascorbic acid content of EPS was 15% higher than that of control. Hardness of EPS was also similar trend. Chlorophil content of cucumber packed with EPS box was 21% higher than that of control. Decay of control was 1-2 pieces per box, but the others was not found. Overall appearence of LD, EPS was better than that of control.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.2
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• pp.87-94
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• 2013

To investigate the effects of functional MA films (FMA) masterbatched by zeolite powder treated with 1 N HCl, 0.5 N NaCl solution and anti-fogging agent (NA) compared with control on the freshness extension of 'Fuji' apples during storage at $15^{\circ}C$. Preference, weight loss, total ascorbic acid, sugar content, acidity, change of gas composition in package were measured. After 150 days of storage, the weight loss of control (L) apples was 1%, that of apple in FMA film (NA) was 1.5% after 150 days. Total ascorbic acid content of apples in control (L) after 150 days was 2.09 mg%, those of apple in FMA film (NA) was 2.72 mg%. The titratable acidity of apple in FMA film was higher than that in control, while soluble solids content of apples in FMA film was lower than that in control after 150 days. Ethylene gas adsorbability in control was 192.2 ppm and those in FMA film was 141.4 ppm after 150 days. Overall, apples in FMA film was better than that of control. It was verified that apples packed with LLDPE film (control) lasted about 130days, while those with FMA films lasted about 170 days. Also, FMA films treated with anti-fogging agent few different compare to nontreated film, but commerdity on the display in market was considered higher than that of non-treated anti-fogging agent.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.170.2-171
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• 2003

최근 식생활의 변화로 쌀 소비량이 감소하면서 쌀 소비확대를 위하여 쌀의 영양적 우수성과 기능성을 강조한 다양한 가공식품 개발이 요구되고 있는 실정이다. 따라서 기존 가공식품의 원료를 쌀로 대체하고자 하는 다양한 연구가 이루어지고 있다. 본 연구는 박력분 대신 쌀가루를 사용하여 파운드케？을 제조하였으며 또한 파운드케？ 제조에 있어서 다량의 유지 사용으로 인한 고열량 문제를 개선하기 위하여 유지 첨가량을 50％까지 감소시키고 그 품질특성을 비교하였다. 쌀을 주원료로 한 파운드케？의 부피는 대조구에 비하여 19% 감소하였으며 유지를 30%, 50％ 감소시킴에 따라 17%, 24% 감소하였다. 비부피 역시 대조구가 1.94 ml/g인 것에 비하여 쌀파운드케？이 1.58 ml/g 그리고 유지 30%, 50% 감소구는 1.72 ml/g, 1.66 ml/g으로 나타났다. 색도 조사 결과 Lightness는 쌀을 주원료로 했을 때 대조구에 비하여 약간 감소하였고 redness는 높거나 비슷하였으며 yellowness는 약간 증가하였으나 유의적인 차이는 보이지 않았다. 쌀파운드케？의 물성 조사 결과 hardness, adhesiveness, gumminess, chewiness는 대조구에 비하여 컸고 유지 첨가량이 감소함에 따라 감소하였으며 springiness, cohesiveness는 대조구에 비하여 작았으며 유지 첨가량이 감소함에 따라 증가하는 것으로 나타났다.

• Food Science and Preservation
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• v.6 no.3
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• pp.260-263
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• 1999

This study was measured weight loss, total ascorbic acids, titratable acidity and soluble solids contents to investigate the effect of EPS(expended polystyrene foam) box. double wall corrugated paperboard box and LDPE film pouches during storage at 25$^{\circ}C$. The rate of weight loss was 5.7% in corrugated paperboard box after 10 days. but those of 20LD, 40LD film and EPS box were 1.0, 0.8, and 0.9%, respectively. Total ascorbic acid content and titratable acidity of EPS box was 15.0% and 24.4% higher than that in corrugated paperboard box, but the obvious differents were not observed among the LDPE film pouches and EPS box. The titratable acidity was decrease during storage, but total soluble solids content was slightly increase. Overall appearences of LDPE pouches and EPS box were boner than those of corrugated paperboard box.

• Journal of the Korean Society for Railway
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• v.18 no.1
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• pp.43-52
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• 2015

In this study, to minimize both the costs associated with track maintenance and the energy consumption for train operation, a numerical method that evaluates the optimal vertical stiffness of a fastener for concrete track is presented. A progress model of the track damage is established in order to calculate the concrete track maintenance cost according to the fastener stiffness. Also, the quantitative relationship between the progress of the track damage and the maintenance of the concrete track is derived. The wheel load is more exactly evaluated by using the advanced vehicle-track interaction model, which can precisely consider the behaviors of the track components. An optimal range for the stiffness of the fastener, a range that is applicable to the design of concrete track for domestic high speed lines, is proposed.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.1
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• pp.35-41
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• 2013

This study investigated the effect of functional MA films (FMA) incorporated with zeolite powder treated with 1 N HCL solution and anti-fogging agent on the freshness extension of Satsuma mandarin. Preference, weight loss, total ascorbic acid, sugar content, titratable acidity and gas composition in package of Satsuma mandarin were evaluated during storage at $15^{\circ}C$. After 120 days of storage, the weight loss of mandarin packed with LLDPE film (control, L) was 1%, FMA film (CA) was 1.6%. Total ascorbic acid content of Satsuma manderin in control was 19.97 mg%, those of CA was 24.25 mg%. The titratable acidity of Satsuma manderin in CA was higher than that of control, while soluble solids content of CA was lower than that of control after 120 days. Ethylene gas content of control was 89.5 ppm and those of CA was 73.6 ppm after 120 days. Quality of Satsuma mandarin packed with CA was better than that of control. It was verified that shelf-life of Satsuma mandarin in control was 100 days and those of CA film was 130 days. Quality of Satsuma mandarin was few different between treated with anti-fogging agent and non-treated, but commodity of film treated with anti-fogging agent was considered better than that of non-treated.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.4 no.2
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• pp.12-17
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• 1998

Weight loss of pear packed with corrugated paperboard box after 50 days storage at $20^{\circ}C$ was 4.4%, and those of 20LD, 40LD film and EPS box were 0.8-0.7%. Ascorbic acid content of EPS was 20% higher than that of control. Hardness of EPS was also similar trend. Titratable acid and total soluble solid content of pear were not different among the packages. Decay of control was 1-2 pieces per box, but the others was not found. Overall appearences of LD, CE and EPS were better than that of control.

• Food Science and Preservation
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• v.6 no.3
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• pp.255-259
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• 1999

This study was measured weight loss, total ascorbic acids, titratable acidity and soluble solids contents to investigate the effect of EPS(expended polystrene foam) box, double wall corrugated paperboard box and LDPE film pouches during storage at 25oC. The rate of weight loss was 5.9% in corrugated paperboard box after 7 days, but those of 20LD, 40LD film and EPS box were 1.1, 1.0, and 1.1% , respectively. Total ascorbic acid content of EPS box was 20% higher than that in corrugated paperboard box, but the obvious differents were not observed among the LDPE film pouches and EPS box. The titratable acidity was decrease during storage, but total soluble solids content was increase. Overall appearences of LDPE pouches and EPS box were better than those of corrugated paperboard box.