• 한국측량학회지
• /
• 제21권4호
• /
• pp.309-316
• /
• 2003

측량을 비롯한 여러 GPS응용분야에서 GPS 수신기에서 수집한 데이터를 빠른 시간 내에 처리하여 정밀 좌표를 산출할 필요성이 발생한다 GPS 데이터 처리에는 현재 네 종류의 GPS 위성궤도력을 이용할 수 있는데, 본 연구에서는 신속한 고정밀 데이터 처리에 가장 적합한 궤도력을 찾기 위해, 각 궤도력을 이용할 경우 성취할 수 있는 좌표성과의 정확성과 정밀도를 비교하였다. GPS 위성에서 제공되는 방송궤도력(broadcast orbits)과 ICS 등의 국제기관에서 제공하는 초신속궤도력(ultra-rapid orbits), 신속궤도력(rapid orbits), 그리고 정밀궤도력(precise orbits)을 이용하였다. 초신속궤도력을 이용하여 GIPSY로 데이터 처리를 하였을 때 일주일 평균 좌표 성과의 정확성이 1.5cm 이내였다. 본 연구를 통하여 GIPSY와 초신속궤도력을 이용하면, 신속한 데이터 처리가 가능한 동시에 고정밀 좌표성과를 얻을 수 있음을 알 수 있었다.

• Clinical and Experimental Reproductive Medicine
• /
• 제27권2호
• /
• pp.191-200
• /
• 2000

Objective: This study was carried out to compare the effects of the stepwise exposure treatments on the morphological normality, fertilization and blastocyst formation rate of the frozen-thawed mouse mature oocytes by vitrification or ultra-rapid freezing and to use as a fundamental data for the cryopreservation of human oocytes. Materials and Methods: The morphological normality and fertilization rates of the vitrified and ultra-rapid frozen mouse mature oocytes after three-stepwise exposure treatments (1step, 3step and 5step) were observed. After choosing the 3step exposure treatment groups, we observed the morphological normality and fertilization, blastocyst formation rate of the vitrified and ultra-rapid frozen mouse mature oocytes. Results: The morphological normality and fertilization rates of the vitrified mouse mature oocytes after three-stepwise exposure treatments (1step, 3step and 5step) were 75%, 85%, 88% and 58%, 61 %, 54% respectively. There were no significant differences among treatments(p>0.05). The morphological normality and fertilization rate of the control was 92% and 65%. There were no significant differences in fertilization rate among control and treatments (p>0.05). The morphological normality and fertilization rates of the ultra-rapid frozen mouse mature oocytes after three-stepwise exposure treatments (1step, 3step and 5step) were 83%, 83%, 84% and 75%, 63%, 56% respectively. There were no significant differences among treatments (p>0.05). The morphological normality and fertilization rate of the control was 95% and 67%. There were no significant differences among control and treatments (p>0.05). The morphological normality and fertilization rate of the vitrified or ultra-rapid frozen mouse mature oocytes after 3step exposure treatment were 69% and 75%, respectively. The blastocyst formation rate was 60% and 57%. The results did not differ significantly between vitrification and ultra-rapid freezing (p>0.05). Conclusion: As known in the above results, there were no significant differences in the fertilization and blastocyst formation rate of the frozen-thawed mouse mature oocytes by vitrification or ultra-rapid freezing among the control and treatments. It is suggested that vitrification and ultra-rapid freezing method were effective for the cryopreservation of mouse mature oocytes.

• Journal of Astronomy and Space Sciences
• /
• 제18권2호
• /
• pp.129-136
• /
• 2001

GPS (Global Positioning System)를 이용한 정밀 응용분야에 있어 위성의 궤도력과 지구자전 상수 (Earth Orientation Parameter, EOP)의 정밀도는 매우 중요한 요소이다. 특히, GPS를 이용한 대기강시 등 신속한 정밀자료처리가 요구되는 응용분야는 실시간 또는 정밀하게 예측된 위성의 궤도력과 EOP를 필요로 한다. 이를 위해 IGS (International GPS Service)는 매일 3시, 15시 (UTC)에 IGU (lGS Ultra Rapid Product)를 생성하여 서비스하고 있다. IGU는 48시간의 정밀 궤도력과 EOP로 구성되어 있는데, 처음 24시간은 관측한 데이터를 처리하여 산출하고 다음 24시간은 예측을 통해서 산출한 값으로 이루어져 있다. 본 논문에서는 독자적인 URP (Ultra Rapid Product)를 산출하기 위한 프로세싱 전략을 수립하고 타당성을 검증하였다. 이를 위해 32개 IGS 관측소의 48시간 관측 자료를 처리하여 URP를 산출하고, 그 결과를 IGS에서 제공하는 여러 정밀 궤도력 및 EOP와 비교하였다.

• 한국측량학회지
• /
• 제22권4호
• /
• pp.383-390
• /
• 2004

IGS는 13일 이후에 제공되는 매우 정확한 최종정밀궤도력을 제공하고 있으며, 보다 신속한 활용을 위해 신속정밀궤도력을 제공하고 있다. 그리고 실시간 활용을 위해 초신속정밀궤도력을 제공하고 있다. 본 연구에서는 최종정밀궤도력을 기준으로 신속정밀궤도력과 초신속정밀궤도력의 정확도를 분석하고, 위성의 위치결정에 필요한 Lagrange 보간법의 차수를 결정하고자 한다. 연구결과, 신속정밀궤도력의 x,y,z좌표의 평균제곱근오차는 $\pm$0.016m 정도였으며, 관측된 초신속정밀궤도력은 약 $\pm$0.024m의 오차를 나타내었다. 24시간동안의 예측 초신속정밀궤도력은 $\pm$0.07m, 6시간동안 예측된 초신속정밀궤도력은 $\pm$0.04m 정도의 오차를 나타내어 방송궤도력보다 매우 높은 정확도를 갖고 있음을 알 수 있었다. 또한, Lagrange 방법으로 위성의 위치를 계산하는 경우, 9차 다항식을 이용하는 것이 효율적임을 확인하였다.

• Structural Engineering and Mechanics
• /
• 제73권4호
• /
• pp.427-436
• /
• 2020

The use of final IGS precise orbit and clock products for high-rate GNSS-PPP proved its effectiveness in capturing dynamic displacement of engineering structures caused by earthquakes. However, the main drawback of using the final products is that they are available after approximately two weeks of data collection, which is not suitable for timely measures after an event. In this study, the use of ultra-rapid products (observed part), which are available after a few hours of data collection, and rapid products, which are available in less than 24 hrs, are investigated and their results are compared to the more precise final products. The tests are designed such that harmonic oscillations with different frequencies and amplitudes and ground motion of a simulated real earthquake are generated using a single axis shake table and the PPP was used to capture these movements by monitoring time-change of the table positions. To evaluate the accuracy of PPP using ultra-rapid, rapid and final products, their results were compared with relative GNSS positioning and LVDT (Linear Variable Differential Transformer) data, treated as reference. The results show that the high-rate GNSS-PPP solutions based on the three products can capture frequencies of harmonic oscillations and dynamic displacement with good accuracy. There were slight differences between ultra-rapid, rapid and final products, where some of the tested events indicated that the latter two produced are more accurate and provide better results compared to the ultra-rapid product for monitoring short-term dynamic displacements.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2007년도 추계학술대회 논문집
• /
• pp.73-74
• /
• 2007

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2007년도 추계학술대회 논문집
• /
• pp.317-318
• /
• 2007

• 미생물학회지
• /
• 제43권4호
• /
• pp.264-272
• /
• 2007

인간면역결핍바이러스(Human Immunodeficiency Virus; HIV) 진단을 위한 초고속 실시간 PCR법을 개발하였다. 검출 대상의 DNA 염기서열은 495염기 HIV-1 특이 env 유전자(gi_l184090)및 294염기 HIV-2 특이 env 유전자(gi_1332355)를 사용하였다. 초고속 실시간 PCR은 microchip에 $6\;{\mu}l$의 PCR 용액을 탑재하는 $Genspector^{TM}$ (Samsung, Korea)을 사용하였으며, PCR의 각 회전 중 단지 두 단계(denaturation, annealing/extension)를 극단적으로 짧은 시간을 주어 수행하게 하였다. 융점분석을 포함한 30회전의 PCR 검색 시간은 총7분30초 이내에 완료되었으며, HIV-1 특이 117염기와 HIV-2 특이 119염기의 PCR산물은 최소 $2.3{\times}10^3$개의 각 env 유전자로부터 30회전의 2단계 초고속 PCR에 의해 성공적으로 증폭시킬 수 있었다. 이러한 초고속 실시간 PCR법은 HIV의 빠른검색뿐 아니라, 다른 병원채의 빠른 검색에도 유용하계 적용될 수 있을 것이다.

• 한국건축시공학회지
• /
• 제7권4호
• /
• pp.109-116
• /
• 2007

Building structures are generally large in size and have a long life, and the construction of such structures requires the investment of a huge amount of money and social infrastructure. Furthermore, building structures are closely related to people's life. Recently, however, the rapid development of society has been worsening air pollution, which is in turn accelerating the degradation of building structures. Thus, the safety of building structure is emerging as a critical issue. To cope with this problem, the government enacted "The Special Act on Safety Control for Infrastructure" but we need engineers' higher concern over the maintenance and reinforcement of existing structures. Recently researches are being made actively on repair mortar using ultra rapid hardening cement for recovering the performance of structures. The present study conducted an experiment on the basic physical properties of ultra rapid hardening mortar for repairing and reinforcing building structures using magnesia cement and mono-ammonium phosphate. In the experiment, we changed the water-cement ratio and carried out replacement at different ratio of MAP/MgO(%). We used retarder to have working life, and made comparative analysis through evaluating working life and fluidity and measuring strength by age.

• 한국전기전자재료학회논문지
• /
• 제17권1호
• /
• pp.21-26
• /
• 2004

Ultra-thin silicon dioxides were grown on p-type(100) oriented silicon employing rapid thermal dry oxidation technique at the temperature range of 850∼1050 $^{\circ}C$. The growth rate of the ultra-thin film was fitted well with tile model which was proposed recently by da Silva ＆ Stosic. The capacitance-voltage, current-voltage, characteristics were used to study the electrical properties of these thin oxides. The minimum interface state density around the midgap of the MOS capacitor having oxide thickness of 111.6 $\AA$ derived from the C-V curve was ranged from 6 to 10${\times}$10$^{10}$ /$\textrm{cm}^2$eV.