• Journal of Advanced Marine Engineering and Technology
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• 제32권3호
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• pp.387-393
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• 2008

This paper has dealt with the probability of oyster shell desiccant cooling system driven by renewable energy of photo-volatic effect with fundamental experiment. The test materials for desiccant are activated charcoal, silica-gel, hi-dry, and oyster shell. The experiments were mainly performed with focusing on the observation of surface features, adsorption amounts of the adsorbent species, and the effect of temperature. Oyster shell has sufficient probability for using as desiccant in a air-conditioning system. Moreover, the heat releasing device would be attached in the system, the system based with oyster shell can be operated with high efficiency.

• 한국정밀공학회지
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• 제14권1호
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• pp.126-141
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• 1997

The purpose of this research is to develope a FEM program for analyzing solidification processes of axisymmetric casting, considering phase changes and the contact between the metal and mold. Tempera- ture recovery method is employed fro considering the phase changes releasing the latent heat and the coin- cident node method is used for calculating the amount of heat transfer between the metal and mold. Tan- gent modulus algorithm is adopted for calculating flow stress and a gap element is employed for modeling the interface between the mold and metal in finding deformed shapes. In order to verify the developed program, axisymmetric aluminum and steel casting processes are simulated. Temperature distribution, phase front position, and shrinkage and porosity creation are compared with measurements, FIDAP results, and good agreements are examined.

• JSTS:Journal of Semiconductor Technology and Science
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• 제2권4호
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• pp.288-294
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• 2002

This paper presents the design, fabrication and characterization of a 32 by 32 electroplated micromirror array on a glass, a low cost substrate. Approaches taken in this work for the fabrication of micromachined mirror arrays include a line addressing scheme, a seamless array design for high fill factor, planarization techniques of polymeric interlayers, a high yield methodology for the removal of sacrificial polymeric interlayers, and low temperature and chemically safe fabrication techniques. The micromirror is fabricated by aluminum and the size of a single micromirror is 200 $\mu\textrm{m}{\;}{\times}200{\;}\mu\textrm{m}$. Static deflection test of the micro-mirror has been carried out and pull-in voltage of 44V and releasing voltage of 30V was found.

• International Journal of Precision Engineering and Manufacturing
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• 제9권4호
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• pp.63-65
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• 2008

The increased interest in reducing the environmental effects caused by releasing organic compounds and aqueous waste has motivated the development of polymeric materials in supercritical fluids. Recently, supercritical fluids have been used in material synthesis and processing because of their special properties, such as high diffusivity, low viscosity, and low surface tension. Supercritical carbon dioxide is the most attractive because it is non-toxic, non-flammable, and has moderate critical temperature and critical pressure values. Supercritical carbon dioxide can also swell most polymers. In this study, we prepared polymer/clay nanocomposites using supercritical fluids. Cloisites 10A, 15A, 25A, and 30B used in this study are montmorillonites modified with a quaternary ammonium salt. The nanocomposites of polymer/clay were characterized by X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry.

• Animal Systematics, Evolution and Diversity
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• 제17권2호
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• pp.171-177
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• 2001

작약도에서 서식하고 있는 쌍뾰족혹히드라(Obelia bicuspidata Clarke, 1875)의 생활사를 서식지와 실험실에서 조사하였다. 쌍뾰족혹히드라는 종히드라과(Campanulariidae)에 속하고 주로 뻘 해안에 있는 작은 바위 또는 굴의 패각에 부착한다. 해파리를 방출하며 해파리 눈(medusa buds)은 일년에 2번, 즉 3월과 6월 사이, 9월과 10월 사이에 발달한다. 폴립 성장의 최적온도는 4-8$^{\circ}C$로 나타났고 수온이 9$^{\circ}C$이상으로 올라가면 퇴화하기 시작하여 수표면 온도가 약 25一되는 8월에는 히드라협이 모두 퇴화하는 것으로 나타났다. 해파리는 작고 폴립에서 방출된 후 약 9일 후 생식선이 발달하였다. 본 연구에서 쌍뾰족혹히드라는 냉수성 종으로 판명되었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.323-323
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• 2013

High power light-emitting diodes (LEDs) are widely used in many device applications due to its ability to operate at high power and produce high luminance. However, releasing the heat accumulated in the device during operating time is a serious problem that needs to be resolved to ensure high optical efficiency. Ceramic or Aluminium base metal printed circuit boards are generally used as integral parts of communication and power devices due to its outstanding thermal dissipation capabilities as heat sink or heat spreader. We investigated the characterisation of electroless plating of Ni-B film according to plating bath temperature, ranging from $50^{\circ}C$ to $75^{\circ}C$ on Ag paste/anodised Al ($Al_2O_3$)/Al substrate to be used in metal PCB for high power LED packing systems. X-ray diffraction (XRD), Field-Emission Scanning Electron Microscopy (FE-SEM) and X-ray Photoelectron Spectroscopy (XPS) were used in the film analysis. By XRD result, the structure of the as deposited Ni-B film was amorphous irrespective of bath temperature. The activation energy of electroless Ni-B plating was 59.78 kJ/mol at the temperature region of $50{\sim}75^{\circ}C$. In addition, the Ni-B film grew selectively on the patterned Ag paste surface.

• Journal of Animal Science and Technology
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• 제65권4호
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• pp.759-766
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• 2023

Visual estrus observation can only be confirmed at a rate of 50%-60%, which is lower than that obtained using a biosensor. Thus, the use of biosensors provides more opportunities for artificial insemination because it is easier to confirm estrus than by visual observation. This study determines the accuracy of estrus prediction using a ruminoreticular biosensor by analyzing ruminoreticular temperature during the estrus cycle and measuring changes in body activity. One hundred and twenty-five Hanwoo cows (64 with a ruminal biosensor in the test group and 61 without biosensors in the control group) were studied. Ruminoreticular temperatures and body activities were measured every 10 min. The first service of artificial insemination used gonadotropin-releasing hormone (GnRH)-based fixed-time artificial insemination protocol in the control and test groups. The test group received artificial insemination based on the estrus prediction made by the biosensor, and the control group received artificial insemination according to visual estrus observation. Before artificial insemination, the ruminoreticular temperature was maintained at an average of 38.95 ± 0.05℃ for 13 h (-21 to -9 h), 0.73℃ higher than the average temperature observed at -48 h (38.22 ± 0.06℃). The body activity, measured using an indwelling 3-axis accelerometer, averaged 1502.57 ± 27.35 for approximately 21 h from -4 to -24 h before artificial insemination, showing 203 indexes higher body activity than -48 hours (1299 ± 9.72). Therefore, using an information and communication techonology (ICT)-based biosensor is highly effective because it can reduce the reproductive cost of a farm by accurately detecting estrus and increasing the rate of estrus confirmation in cattle.

• 한국잠사곤충학회지
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• 제52권2호
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• pp.123-128
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• 2014

2010년부터 2011년까지 2년간 국립농업과학원 내 포장 및 기타 주요 조사지에서 관찰한 일본납작진딧물의 생태학적 특성은 다음과 같다. 1. 이대 내 일본납작진딧물 접종방법 조사결과, 이대 잎에 핀으로 꼽아 접종하는 것보다 핀으로 털어 접종하는 방법이 더 유효하였으며, 노지, 비닐하우스, 반딧불이 망실보다 유리온실구가 접종율이 좋았다. 2. 일본납작진딧물의 겨울철 생존온도 조사를 실시한 결과, 일산호수공원과 구리생태공원은 2010년 1월 7일과 1월 15일 $-15^{\circ}C$ 이하로 조사되어 이대 생육한계 온도인 $-10^{\circ}C$ 이하이었다. 본 조사 결과 현재까지 이대 및 이대를 흡즙하는 일본납작진딧 물이 서식할 수 있는 겨울철 최저 온도 조건 지역은 한강 이남인 보라매공원과 수원 곤충생태원 포장으로 조사되었다. 3. 수원 곤충생태원 포장 내 최저 온도 조사에서는 곤충생태원 노지가 1월 17일 $-17.5^{\circ}C$로 조사되어 역시 이대 및 일본납작진딧물이 서식할 수 없는 조건이었다. 따라서 이대를 식재하여 일본납작진딧물을 도입하여 사육하기 위해서는 유리온실이 가장 적합한 것으로 조사되었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1629-1630
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• 2006

This paper describes a micro total analysis system ($\mu$ TAS) for detecting and digesting the target protein which includes a bead based temperature controllable microchip and computer based controllers for temperature and valve actuation. We firstly combined the temperature control function with a bead based microchip and realized the on-chip sequential reactions using two kinds of beads. The PEG-grafted bead, on which RNA aptamer was immobilized, was used for capturing and releasing the target protein. The target protein can be chosen by the type of RNA aptamer. In this paper, we used the RNA aptamer of HCV replicase. The trypsin coated bead was used for digesting the released protein prior to the matrix assisted laser desorption ionization time of flight mass spectrometer (MALDI TOF MS). Heat is applied for release of the captured protein binding on the bead, thermal denaturation and trypsin digestion. PDMS microchannel and PDMS micro pneumatic valves were also combined for the small volume liquid handling. The entire procedures for the detection and the digestion of the target protein were successfully carried out on a microchip without any other chemical treatment or off-chip handling using $20\;{\mu}l$ protein mixture within 20 min. We could acquire six matched peaks (7% sequence coverage) of HCV replicase.

• 한국발생생물학회지:발생과생식
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• 제25권4호
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• pp.269-277
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• 2021

Effects of water temperature and hormones on ovarian development of conger eel in Korea were investigated. Ovarian development was analyzed by measuring gonadosomatic index (GSI) and oocyte diameter with histological methods. At rearing water temperatures of 12℃, 14℃, and 16℃, GSI value increased from 3.66 at the start of the experiment to 7.44, 8.82, and 7.34 at the end of the experiment, respectively. At rearing water temperatures of 12℃, 14℃, and 16℃, egg diameter increased from 245.11-300.25 ㎛ at the start of the experiment to 377.62-480.27 ㎛, 396.72-498.54 ㎛, and 382.29-475.69 ㎛ at the end of the experiment, respectively. Follicular oocyte development revealed that primary yolk globule stage observed from January to March. It entered to secondary yolk globule stage in April and remained at the same stage until July. As a result of examining effects of three hormones (human chorionic gonadotropin (HCG), luteinizing hormone releasing hormone analogue (LHRHa), and salmon pituitary extraction (SPE) on ovarian development, HCG was found to be the most effective one. The progress from diapause of the secondary yolk globule stage to migratory nucleus stage of oocytes could be induced by treating fish with HCG at 1,000 IU/kg. The effect of hormone treatment on ovarian development of conger eel in Korea was the most effective at water temperature of 14℃.