A gasketed plate heat exchanger(GPHE) requires a much smaller installation space than a shell & tube heat exchanger because of its compact and good thermal performances. However, GPHEs have a disadvantage of being relatively vulnerable to high temperature and pressure due to rubber gaskets. To overcome a GPHEs’ disadvantage, Welded Block type Plate Heat Exchangers(WBPHE) have been developed. The flow pattern and heat transfer principle of WBPHE are very similar to GPHEs, so they are very compact and can be applied to high temperature and pressure. In this study, the structure and characteristics of WBPHE are briefly introduced, and its thermal performances were conducted experimentally using hot and cold water in the Reynolds number’s range from 5,500 to 10,000. Test results were compared with the experimental correlations of other researchers, which shows that significant deviations were noticed in the heat transfer coefficient predictions with a deviation range from 31% to 85%. The previous friction factor correlations also predicted the current results with big errors from 25% to 45%. These deviations are expected to be due to different chevron angles between previous studies and the current study, and also the end-plate effect is expected to be one of the potential causes that led to these deviations.

The purpose of this study was to optimize the rice protein extracted using a response surface methodology. The experiment was designed based on a CCD (Central Composite Design), and the independent variables were the high pressure (X1, 0-400 MPa) and processing time (X2, 0-10 minutes). The results of the extraction content (Y1), residue content (Y2), and recovery yield (Y3) were fitted to a response surface methodology model (R2= 0.92, 0.92, and 0.93, respectively). Increasing the pressure and processing time has a positive effect on the extraction content (Y1), residue content (Y2), and recovery yield (Y3). Therefore, these high-pressure conditions (independent variables) can significantly affect the improvement in rice protein extraction efficiency. Thus, the optimal conditions of X1 and X2 were 400 MPa and 10 min., respectively. Under these optimal conditions, the predicted values of Y1, Y2, and Y3 were 62.93, 57.53 mg/g, and 91.76%, respectively.

This study was carried out to produce stable evening primrose oil in water emulsion by using various emulsifier with HLB (8.6, 12, 16.7), concentration (0-45%) and emulsification methods such as high-speed emulsification (7,000 rpm, 2 min) and high-pressure homogenization (10,000 psi, 1 cycle). And then properties of evening primrose oil in water emulsion was evaluated with keeping at room temperature and 40oC during 28 days. Lower HLB 8.6 and high viscosity emulsifier added emulsions were not appropriate for high-pressure homogenization and were separated in a day. The optimum emulsification condition was HLB 12 and high-pressure homogenization (10,000 psi, 1 cycle) for evening primrose oil in water emulsion. These emulsions produced by optimum condition were not separated with the aqueous phase and the oil phase and they were nano-sized around 200 nm, higher zeta-potential (±mV), mono-polydispersed (<0.3), and less oxidized (<0.4) during 28 days.

Recently, automobile washing methods have been carried out using steam of high temperature and high pressure instead of water. Therefore, it is necessary to secure the structural stability of the steam tank. In this study, it is necessary to reduce the weight of the steam tank by reducing the thickness of the existing steam tank by about 25%. The safety of the product design was verified through simulation to ensure the robustness of the product by securing the structural stability and fatigue analysis at high temperature and pressure of the steam tank according to the weight reduction. For newly developed products compared to existing models.

In this study, temperature and pressure of guided wave radar products are transmitted at high temperature and high pressure. In the case of transmission of temperature pressure, high temperature and high pressure steam leak from the guide rod part to the atmosphere causes the failure. Therefore, in this study, structural analysis and thermal flow analysis of the product are performed to identify the problem of the product, so as to prevent leakage in the product development by grasping the cause of the leakage of the product. In this study, if the method of assembling the lower end of the piston rod and the gasket is changed from line contact to face contact,

Plant growth and morphology are affected by light environments. The morphogenesis and growth of the plants growing in plant factories are different from those grown under sunlight due to the effect of far-red light included in sunlight. The objective of this study was to compare the morphogenesis and growth of cucumber plants grown under artificial sunlight, high pressure sodium lamp (HPS), and HPS with additional far-red light (HPS+FR). The artificial solar (AS) with a spectrum similar to sunlight was manufactured using sulfur plasma lamp, incandescent lamp, and green-reducing optical film. HPS was used as a conventional electrical light source and far-red LEDs were added for HPS+FR. The optical properties of each light source was analyzed. The morphogenesis, growth, and photosynthetic rate were compared in each light source. The ratio of red to far-red lights and phytochrome photostationary state were similar in AS and HPS+FR. There were significant differences in morphology and growth between HPS and HPS+FR, but there were no significant differences between AS and HPS+FR. SPAD was highest in HPS, while photosynthetic rate was higher at AS and HPS. Although the photosynthetic rate in HPS+FR was lower than HPS, the growth was similar in AS. It was because canopy light interception was increased by longer petioles and larger leaf areas induced by FR. It is confirmed that the electrical light with additional far-red light induces similar photomorphogenesis and growth in sunlight spectrum. From the results, we expect that similar results will be obtained by adding far-red light to electrical light sources in plant factories.

The 3-way valve have been used as a valve for opening and closing the valve by the flow control in the pressure system of the cryogenic and high pressure environment. In this paper, numerical analysis and experimental study on fracture nipple of 3-way ultra high pressure valve applied to space launch vehicle was carried out. We have developed a 3-way valve numerical simulation modeler of cryogenic environment using commercial software ANSYS 18.2. As results of numerical analysis, optimum nipple condition was derived. In addition, a 3-way valve prototype was fabricated and the fracture test was performed and compared with the numerical analysis results.

본 연구에서는 발아와 고압처리에 따른 검정콩 조사포닌 추출물의 in-vitro 항암 활성을 확인하기 위하여 검정콩을 발아시킨 후 고압처리하고, 조사포닌 추출물을 제조한 후 인체 유래 유방암(MCF-7), 대장암(HCT-116), 전립선암(PC-3) 및 위암(AGS) 세포주에 대한 증식억제효과를 검토하였다. 대조구의 조사포닌 추출물은 400 μg/mL 농도에서 4종의 암세포주에 대하여 67.02~91.70% 범위의 생존율을 보여 항암 효과가 낮았지만, 발아 4일차 콩을 150 MPa의 압력에서 고압처리한 검정콩의 조사포닌 추출물은 23.94~57.37% 범위의 생존율을 보여 발아와 고압처리에 의해 암세포 성정억제효과가 증가하였다. 특히, 위암세포(AGS)의 경우 다른 세포주에 비해 저농도에서도 세포증식효과를 보여 가장 높은 암세포 증식억제 효과를 나타내었다. 이상의 결과로부터 항암 활성을 나타내는 Soyasaponin, B group의 soyasaponin 및 soyasapogenol의 함량은 발아와 고압처리에 의해 증가하였고, 고압처리 발아콩으로부터 항암 활성을 나타내는 사포닌 추출물의 개발이 가능할 것으로 생각된다. 또한, 추후 항암 활성 물질의 분리동정과 메커니즘 규명에 대한 연구가 수행되어야 할 것으로 판단된다.

인공광을 이용한 보광은 시설재배에서 작물의 정상적인 생육과 수확량을 유지하고 품질 향상을 위하여 사용되는 실용적인 방법이다. 본 연구의 목적은 황 플라스마 램프(SP)와 고압 나트륨 램프(HPS)의 보광이 파프리카의 생육 및 수확량에 미치는 영향을 조사하는 것이다. 생장상에서는 SP 및 HPS를 기본 광원으로, 온실에서는 보광으로 사용하여 작물 생육에 미치는 효과를 비교 분석하였다. 생장상에서는 정식 2 주 후 SP와 HPS 하에서 초장, 엽면적, 줄기 직경, 엽수, 생체중 및 건물중을 매주 측정 하였다. 온실재배에서는 무보광을 대조구로 하였다. 보광은 07:00부터 21:00까지 외부일사 100W·m-2 미만일 때 처리되도록 하였다. 보광 처리 후 3주부터 매주 생육량을 측정하였고, 2주 마다 수확하여 과실수와 과실무게를 측정하였다. 생장상에서는 높은 광합성속도로 인하여 SP가 HPS보다 생육이 양호하였고, 온실에서는 보광처리가 대조구보다 수확량이 유의적으로 높았다. 온실에서의 초장, 마디수, 엽장, 생체중, 건물중은 SP와 HPS 간의 유의적인 차이는 없었다. 그러나 수확 시 과실수와 수량은 광합성 증진과 및 과실수의 증가로 인하여 SP에서 많았다. SP는 태양광과 유사한 광 스펙트럼을 보였으나, HPS와 비교하여 높은 PAR과 적색과 원적색 파장의 광양자속의 합이 높았기 때문에 파프리카의 광합성과 수확량을 증가시켰다.

바다속 60 km 깊이의 수압과 같은 압력을 사용하여 순간적이고 균일한 압력전달로 가열공정을 최소화함으로써 신선한 맛과 향, 텍스처, 비타민의 유지 등 품질보존을 할 수 있는 기술인 HPP는 식중독과 부패미생물을 억제하는 효과를 가져올 수 있는 기술로 현재 가장 활발히 연구되고 있는 분야이다. 기존의 열처리가 단백질의 변성, 화학적 변화, 전분의 호화, 효소의 활성에 영향을 미쳐서 보존성을 유지한다면 HPP는 열처리의 장점은 그대로 갖고 있으면서 열처리에서 야기되는 원치 않는 화학적 변화를 최소화할 수 있다는 장점을 갖고 있다 보존기간이 길어 소비자들이 우려하는 첨가물의 사용이 필수적인 육류가공품에 대해서는 초고압처리에 대한 국내 연구가 미비하여 본 연구에서는 대표적인 육가공품인 슬라이스햄에 대해 600MPa 초고압처리(0분, 4분, 6분)가 이들의 신선도에 미치는 영향을 실험하였다. 수분함량은 48~69%, 염도 1.07-1.11%에서 변화를 보이고 있었고, pH는 처음 6.4-6.5에서 6.1-6.15까지 낮아졌으나 대조군과 처리군간의 차이는 나타나지 않았다. 초고압처리 후 20oC에서 보관한 일반세균 결과는 4주까지 모든 군에서 미미한 수준에서 일반미생물이 발견되었으나 5주부터는 대조군과 HPP 6분 처리군에서 105을 초과하였고 7주에는 4분 처리군, 6분처리군에서 식품으로 섭취가 불가능한 106을 초과하는 것으로 나타났다. 대장균군은 20oC 가중실험으로 7주간 관찰하였음에도 불구하고 모든 군에서 대장균군이 발견되지 않았다. 육류의 단백질 신선도 판정에 사용되는 방법인 VBN은 4주차까지는 1 mg% 미만의 VBN값을 보였고 5주부터는 1~2 mg%의 값을 나타냈다. 그러나 군별 차이는 나타나지 않았다(p > 0.05). 육의 조직내 지방 산패 정도의 지표로 사용되는 TBA는 7주가 끝날 때까지 0.18 mgMA/kg 이하였고 이 수치는 신선육의 범위에 들며, 처리군별 차이를 보이지 않았다. 본 실험에서는 포장재의 변성이 발생하지 않았고 가스의 발생으로 인한 부풀어 오름도 발생하지 않았는데, HPP의 효과가 전혀 관찰되지 않은 사실은 포장재의 밀착으로 인한 공기와의 차단만으로 기본적인 보존 효과를 보인 것이 아닌가 사료된다.

The investigation on the lightweight of automobiles has been underway in commercial vehicles as well as passenger cars due to global warming and strengthening of European emission standards. In this study, the V-arm were developed for lightweight parts using aluminum alloy instead of steel with high pressure die casting processing. This study has focused on lightweight adaptive concept design. Several models of V-arm were designed and analyzed for the fluidity and solidification. V-arm was produced with ADC12 by high pressure die-casting process. The mechanical properties of developed V-arm were measured; such as tensile strength, elongation, shear strength, and durability. The possibility of mass production with the light weight aluminum V-arm substitute from the steel. The weight was reduced about 38% from 16kg to 9.98kg. The productivity was improved with decreasing the process from 8 to 5 by All-in-0ne process using high pressure die-casting.