• 한국세라믹학회지
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• 제24권3호
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• pp.223-226
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• 1987

Among many densification routes for silicon nitride, HIP(hot isostatic pressing) is becomming more popular these days, mainly due to the fact that it can produce highly reliable products with superior mechanical properties. This study involves in sintering of silicon nitride followed by HIP which requires no canning. Various property changes curing sintering and HIP are observed and analyzed in terms of microstructural changes. Porosity decrease and enhanced interlocking of grains by HIP are considered to be the major causes for improved mechanical properties of silicon nitride.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.610-615
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• 2001

In the interest of improved automotive fuel economy, one solution is reducing vehicle weight. Achieving significant weight reductions will normally require reducing the panel thickness or using alternative materials such as aluminum alloy sheet. These changes will affect the dent resistance of the panel. In this study, the correlation between panel size, curvature, thickness, material properties and dent resistance is investigated. A parametric approach is adopted, utilizing a "design software" tool incorporating empirical equations to predict denting and panel stiffness for simplified panels. The developed design program can be used to minimize panel thickness or compare different materials, while maintaining adequate panel performance.

• 한국분말재료학회지
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• 제9권5호
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• pp.303-306
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• 2002

P/M high speed steels with various Co contents were fabricated by gas atomization and Canning/HIP process. As Co content in P/M high speed steel increased, hardness, transverse rupture strength and yield strength in compressive testing increased due to solid solution hardening of Co in matrix. Especially, PM high speed steels with Co have high deformation resistance to repeated compressive loading.

• 한국식품과학회지
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• 제3권1호
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• pp.25-28
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• 1971

Aspergillus saitoi가 생산(生産)하는 섬유소분해효소(纖維素分解酵素)의 생산조건(生産條件)과 밀감내과피(內果皮)의 탈피효과(脫皮效果)를 검토한 결과(結果)는 다음과 같다. 1. Asp. saitoi의 배양최적(培養最適) 온도(溫度)는 $30^{\circ}C$, 시간(時間)은 72시간(時間)에서 섬유소(纖維素) 생성능(生成能)이 가장 좋았다. 2. 본효소(本酵素)를 10배(倍) 농도로 희석하여 (희석효소액 : 밀감 2 : 1) $40^{\circ}C$의 항온조(恒溫槽)에서 $3.5{\sim}4$시간(時間) 작용(作用)시킨 것이 탈피정도(脫皮程度), 풍미(風味), 광택(光澤)이 우수하여 밀감 syrup 통조림 제조조건으로 최적(最適)이었다.

• 산업경영시스템학회지
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• 제40권1호
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• pp.165-172
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• 2017

Machines are physically or chemically degenerated by continuous usage. One of the results of this degeneration is the process mean shift. Under the process mean shift, production cost, failure cost and quality loss function cost are increasing continuously. Therefore a periodic preventive resetting the process is necessary. We suppose that the wear level is observable. In this case, process mean shift problem has similar characteristics to the maintenance policy model. In the previous studies, process mean shift problem has been studied in several fields such as 'Tool wear limit', 'Canning Process' and 'Quality Loss Function' separately or partially integrated form. This paper proposes an integrated cost model which involves production cost by the material, failure cost by the nonconforming items, quality loss function cost by the deviation between the quality characteristics from the target value and resetting the process cost. We expand this process mean shift problem a little more by dealing the process variance as a function, not a constant value. We suggested a multiplier function model to the process variance according to the analysis result with practical data. We adopted two-side specification to our model. The initial process mean is generally set somewhat above the lower specification. The objective function is total integrated costs per unit wear and independent variables are wear limit and initial setting process mean. The optimum is derived from numerical analysis because the integral form of the objective function is not possible. A numerical example is presented.

• 한국수산과학회지
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• 제29권6호
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• pp.900-908
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• 1996

Changes of paralytic shellfish toxin components and specific toxicity in blue mussel, Mytilus edu/is and oyster, Crassostrea gigas during canning process were investigated by high performance liquid chromatography (HPLC). The $mole\%$ of the frozen shucked blue mussel were in order of $27.5\;mole\%$ of gonyautoxin 1, $23.0\;mole\%$ of gonyautoxin 8 (C1) and $23.0\;mole\%$ of epi-gonyautoxin 8 (C2), while those of the frozen shucked oyster were in order of $29\;mole\%$ of C1, $22\;mole\%$ of C2, $16.7\;mole\%$ of gonyautoxin 2. Both samples had minor amounts of saxitoxin and neosaxitoxin. On the other hand, in case of specific toxicity, the major toxins were consisted of gonyautoxin $1\~4$ in both sample. The toxicity of gonyautoxin $1\~4$ were 88 and $84\%$ in blue mussel and oyster, respectively. According to the experimental results, C1, C2 and gonyautoxin 4 were very sensitive to heat treatment, while gonyautoxin 2 and saxitoxin were pretty heat resistant than any other toxin components.

• 대한기계학회논문집A
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• 제35권11호
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• pp.1471-1476
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• 2011

자동차 배기계의 앞쪽에 배치된 촉매변환기는 배기가스 중 유해한 성분을 무해한 것으로 변환하는 제품이다. 이것의 중심부인 담체는 단면의 윤곽이 원형이나 타원형이고 내부는 미세한 격자형 벽으로 채워진다. 담체를 매트로 두르고 캔에 넣는 캐닝공정 중 과대한 압력을 받아서 담체가 취성파괴될 것이 염려된다. 담체의 파괴를 방지하고자 매트의 압력의 분포를 예측하는 유한요소 프로그램을 개발하였다. 이것은 Microsoft EXCEL로 작성되어 입출력이 모두 간편하다. 담체는 강체, 캔은 선형탄성체로 단순하게 취급하고 매트의 재료비선형성을 고려하였다. 캔은 굽힘과 균일인장이나 압축에 저항하는 것으로 모델링하였다. 편의상 요소의 갯수는 35개, 반복 횟수는 20회로 제한하였다. ABAQUS의 해석결과와 잘 일치하여 본 프로그램의 타당성을 입증하였다.

• 한국수산과학회지
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• 제33권5호
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• pp.399-402
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• 2000

일반적인 수산물 통조림의 내용물 속에는 물, 기름 및 조미액즙 등 packing medium이 들어있다. 본 연구에서는 새우, 꽁치 및 굴을 원료로 건조 및 조미 후 packing medium이 없는 새로운 형태의 조미통조림을 제조하고 이들 제품의 진공도별 (15, 30, 45 및 60cmHg) 열침투 특성을 조사할 목적으로 본 연구를 수행하였다. 진공도별 제품의 열침투 속도는 진공도가 높을수록 빠르게 나타났으며 동일시간 살균했을 때 진공도가 높을수록 Fo치가 높게 나타났다. 한편 상법으로 제조된 water pack과 본 시험에서 제조한 조미통조림과의 열침투 속도를 비교했을 때 새우와 꽁치 조미통조림의 경우는 진공도 15cmHg 이상에서는 열침투 속도가 water pack 제품보다는 빠르게 나타났고 굴 제품의 경우는 water pack 제품이 30cmHg 이상에서 열침투 속도가 빠르게 나타났다. 따라서 packing medium이 없는 조미 통조림의 경우 진공도 30cmHg 이상이 되면 기존의 water pack 제품보다 열침투 속도가 빠르다는 사실이 관찰되었다.

• 대한기계학회논문집A
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• 제21권1호
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• pp.73-82
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• 1997

High temperature densification behaviors of alumina powder compacts were investigated under hot pressing and hot isostatic pressing. An alumina part of valve-head shape was fabricated under hot pressing and its forming process was simulated by finite element calculation. an alumina powder compact encapsulated by a stainless steel container was also densified under hot isostatic pressing. Inhomogeneous deformations during hot isostatic pressing due to the canning effect were observed experimentally and predicted by finite element analysis.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2309-2312
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• 2003

This paper presents the minimization of the energy costs based on energy saving for industrial retort process of canned food. The approved proposed method is related the optimal steam or hot water flow control to achieve desired temperature of retort process. The smooth response and zero steady state error can be also achieved. The performances of the proposed control technique were observed using a small tuna canned food plant in Thailand as an illustrative example. The experimental results are given to support the saving in energy costs and some benefits of the proposed technique.