• 한국자원식물학회지
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• 제28권2호
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• pp.243-252
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• 2015

본 연구는 제주특산식물인 좀향유의 현지 내･외 보존을 위한 기초 연구로서 증식체계를 마련하고 전처리제 처리에 따른 발근 특성과 시비에 따른 유묘의 생장 효과를 등을 알아보았다. 온실과 밀폐상의 온습도 조사결과 평균 온도는 비슷하였으나 공중 습도는 온실보다 밀폐상이 높은 습도를 유지하였으며, 좀향유 삽목 후 온실은 10일, 밀폐상은 7일만에 최초 발근을 확인하여 밀폐상의 빠른 발근율을 보였으며 온실과 밀폐상에서의 생존율, 발근율, 뿌리수 등은 근소하게 밀폐상이 높게 조사되어 온실보다 밀폐상이 효과적이었다. 발근억제물질 제거를 위한 전처리제 처리는 AgNO₃ 77.5%를 제외한 다른 처리구에서 95% 이상의 높은 발근율로 조사되어 좀향유의 경우 발근억제 물질은 적은 것으로 판단된다. 유묘의 용기별 질소 시비량 및 Osmocote 시비시험 결과 시비량과 용기의 조건에 따라 생존율과 생장 등에 차이를 보였다. 배양판에서 완효성 비료인 Osmocote를 시비한 결과 생존율, 지상부, 지하부 생장 등이 가장 양호하여 좀향유의 유묘 증식을 위해서는 Osmocote 시비가 바람직 할 것으로 판단된다.

• 한국정밀공학회지
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• 제23권3호
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• pp.163-170
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• 2006

Thin films play an important role in many technological applications including microelectronic devices, magnetic storage media, MEMS and surface coatings. It is well known that a thin film's material properties can be very different front the corresponding bulk properties and thus there has been a strong need for the development of a miniature tester to measure the mechanical properties of a thin film. Two testers are designed and set up in small size of 62 mm width, 20 mm depth and 90-120 mm height to fit in a chamber of scanning electron microscope (SEM). One tester has a homemade 0.2 N load cell and a low-priced electromagnetic actuator. The other has a commercial 5 N load cell, a $52{\mu}m$ piezoelectric actuator and some novel grips. Two types of 3.5 microns thick polysilicon specimen are tested to prove the testers' applicability. The strain is measured by the two ways. Firstly, it is measured by an ISDG system in the atmosphere far the reference. Secondly, the same test is repeated in a SEM chamber to monitor the strain as an in-situ experiment. The strain is evaluated by observing the gap change between two markers.

• Corrosion Science and Technology
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• 제23권2호
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• pp.113-120
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• 2024

An attempt was made to apply digital image correlation (DIC) strain analysis to in-situ scanning electron microscopy (SEM) observations of bending deformation to quantify local strain distribution inside a ZnMgAl-alloy coating in deformation. Interstitial-free steel sheets were hot-dipped in a Zn-3Mg-6Al (mass%) alloy melt at 400 ℃ for 2 s. The specimens were deformed using a miniature-sized 4-point bending test machine inside the SEM chamber. The observed in situ SEM images were used for DIC strain analysis. The hot-dip ZnMgAl-alloy coating exhibited a solidification microstructure composed of a three-phase eutectic of fine Al (fcc), Zn (hcp), and Zn2Mg phases surrounding the primary solidified Al phases. The relatively coarsened Zn₂Mg phases were locally observed inside the ZnMgAl-alloy coating. The DIC strain analysis revealed that the strain was localized in the primary solidified Al phases and fine eutectic microstructure around the Zn₂Mg phase. The results indicated high deformability of the multi-phase microstructure of the ZnMgAl-alloy coating.

• 한국지반공학회지:지반
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• 제13권4호
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• pp.109-120
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• 1997

공용하중 상태에서 지반이 경험하는 변형률 크기는 0.1~1% 미만임이 밝혀지고 있다. 변형특성을 보다 엄밀히 평가하기 위하여는 미소변형률 영역에서의 신뢰성 있는 변형측정이 가능한 현장시험기기의 개발이 필요하다. 본 연구의 목적은 공내째하시험기(PMT)를 사용하여 지반의 미소변형률 전단탄성계수를 측정하는 것이다. 공내재하시험에서 시추공 설치에 따른 주위 지반의 교란효과를 제거하기 위하여 초기 하중재하단계가 아닌 역재하-재재하 단계에서 PMT 주위지 반의 응력상태 및 변형률 크기를 고려하여 미소변형률 잔단탄성계수를 결정하였다. 실내 토조에서 성형한 모래시료와 화강풍화토 현장지반에서 시험을 수행하였으며,시험결과로부터 본 연구 에서 사용한 PMT시험은 변형률 크기 10-2%~0.5% 범위에서 신뢰성 있는 전단탄성계수 측정이 가능하였다. 또한 변형률 크기를 고려하여 다른 실내외시험에서 결정된 전단탄성계수와 비교 하면 서로 잘일치하는 결과를 얻을 수 있었다.

• 한국자동차공학회논문집
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• 제9권4호
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• pp.1-9
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• 2001

The soot yield has been studied by a premixed propane-oxygen-inert gas combustion in a specially designed disk-type constant-volume combustion chamber to investigate the effects of pressure, temperature and turbulence on soot formation. Premixtures are simultaneously ignited by eight spark plugs located on the circumference of chamber at 45 degree intervals in order to observe the soot formation under high pressures. The eight flames converged compress the end gases to a high pressure. The laser schlieren and direct flame photographs for observation field with 10 mm in diameter are taken to examine into the behaviors of flame front and gas flow in laminar and turbulent combustion. The soot volume fraction in the chamber center during the final stage of combustion at the highest pressure is measured by the in situ laser extinction technique and simultaneously the corresponding burnt gas temperature by the two-color pyrometry method. The pressure and temperature during soot formation are changed by varying the initial charge pressure and the volume fraction of inert gas compositions, respectively. It is found that the soot yield increases with dropping temperature and rising pressure at constant equivalence ratio, and that the soot yield of turbulent combustion decreases in comparison with that of laminar combustion because the burnt gas temperature increases with the drop of heat loss.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.222-222
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• 2011

Titanium dioxide (TiO2) has a number of applications in optics and electronics due to its superior properties, such as physical and chemical stability, high refractive index, good transmission in vis and NIR regions, and high dielectric constant. Atomic layer deposition (ALD), also called atomic layer epitaxy, can be regarded as a special modification of the chemical vapor deposition method. ALD is a pulsed method in which the reactant vapors are alternately supplied onto the substrate. During each pulse, the precursors chemisorb or react with the surface groups. When the process conditions are suitably chosen, the film growth proceeds by alternate saturative surface reactions and is thus self-limiting. This makes it possible to cover even complex shaped objects with a uniform film. It is also possible to control the film thickness accurately simply by controlling the number of pulsing cycles repeated. We have investigated the ALD of TiO2 at 100$^{\circ}C$ using precursors titanium tetra-isopropoxide (TTIP) and H2O on -O, -OH terminated Si surface by in situ X-ray photoemission spectroscopy. ALD reactions with TTIP were performed on the H2O-dosed Si substrate at 100$^{\circ}C$, where one cycle was completed. The number of ALD cycles was increased by repeated deposition of H2O and TTIP at 100$^{\circ}C$. After precursor exposure, the samples were transferred under vacuum from the reaction chamber to the UHV chamber at room temperature for in situ XPS analysis. The XPS instrument included a hemispherical analyzer (ALPHA 110) and a monochromatic X-ray source generated by exciting Al K${\alpha}$ radiation (h${\nu}$=1486.6 eV).

• 농업과학연구
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• 제45권4호
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• pp.695-706
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• 2018

This study was conducted to investigate the effect of a steam chamber type on the ruminal fermentable characteristics and nutrient degradabilities of corn flakes in Hanwoo. Three Hanwoo equipped with a ruminal fistula were used as experimental animals. There were two treatments: Corn flake using a steam chamber (CFSC, 1.0 atm - $100^{\circ}C$ 96 min) or corn flake using a pressurized steam chamber (CFPSC, 1.5 atm - $111^{\circ}C$ 12 min), respectively. In the in vitro trial, the ruminal pH was significantly lower in the CFPSC than in the CFSC (p < 0.01). The ammonia concentration was increased by 14.1% in the CFPSC compared to the CFSC (p < 0.05). The concentration of acetic acid was higher in the CFSC than in the CFPSC (p < 0.01). The concentrations of propionate, butyrate and total-VFA at 24 and 48 h were higher in the CFPSC than in the CFSC (p < 0.05). In the in situ trial, the degradability of dry matter was significantly higher in the CFSC than in the CFSC (p < 0.01). In addition, the degradabilities of starch and crude protein were significantly higher in the CFSC than in the CFSC (p < 0.01). Thus, the present results indicate that the pressurized steam chamber could be recommended to improve the feed value of corn flake according to the increase in the starch degradability and volatile fatty acid production.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1359-1364
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• 2008

It is well known that the standard penetration test (SPT) has been used in all over the world to get geotechnical properties of the ground. However, it is difficult to apply the SPT to the dense sand, gravel, weathered rock, etc. For the application of the SPT in these grounds, it is necessary to change in the diameter and the impact energy of the SPT. For the improvement of site investigation technology, Large Penetration Testing device (KICT-type LPT) was developed and applied to the in situ condition. The drop height and weight of the hammer in developed system were decided as 760mm and 150kg, respectively. And the developed sampler has the inner diameter of 63 mm and the length of 500 mm with the adjustment of energy ratio to the SPT of 1.5. In this study, the performance of KICT-type LPT was evaluated by using a calibration chamber system and pile driving analyzer (PDA)

• Journal of Advanced Marine Engineering and Technology
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• 제23권3호
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• pp.300-310
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• 1999

A constant-volume combustion chamber is developed to measure the burnt gas temperature over the wide ranges of equivalence ratio from 1.5 to 2.7 and pressure from 0.1 to 2.7 and pressure from 0.1 to 6 MPa by two-color method. The combustion temperature is also calculated by the conventional two-region model. The premixed fuel rich propane-oxygen-inert gas mixtures under high pressures are simultaneously ignited by eight spark plugs located on the circumference of combustion chamber with 45 degree intervals. The eight converging flames compress the end gases to high pressures. The transmissiv-ity in the chamber center during the final stage of combustion at the highest pressure is measured by in situ laser extinction method. Comparisons are made with the combustion temperatures between two-color method and two-region model. It is found that the burnt gas temperature mea-sured by two-color method is higher than that calculated by two-region model because of being the negative temperature gradient on the calculation and the temperature distribution of light path-length on the measurement and the burnt gas temperature for the turbulent combustion is higher than that of the laminar combustion under the same conditions because the heat loss for turbulent combustion is lower due to the shorter combustion period.

• 한국초전도ㆍ저온공학회논문지
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• 제8권3호
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• pp.18-22
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• 2006

We obtained in-situ $MgB_2$ thin films in an one-step process using ESSD (Evaporation Sputtering Simultaneous Deposition) method. In our approach. the Ma evaporator is designed specially Mg and B are simultaneously evaporated and sputtered, respectively, in the specially designed ESSD chamber. The background pressure was less than $1{\times}10^{-6}$ Torr. The substrate temperature was kept at 623 K. The film properties were investigated by both electrical resistivity and PPMS. As a result, typical $T_c$ of films was 11 K.