• Title/Summary/Keyword: g-operations

Search Result 538, Processing Time 0.032 seconds

MINERVA: SMALL PLANETS FROM SMALL TELESCOPES

  • WITTENMYER, ROBERT A.;JOHNSON, JOHN ASHER;WRIGHT, JASON;MCCRADY, NATE;SWIFT, JONATHAN;BOTTOM, MICHAEL;PLAVCHAN, PETER;RIDDLE, REED;MUIRHEAD, PHILIP S.;HERZIG, ERICH;MYLES, JUSTIN;BLAKE, CULLEN H.;EASTMAN, JASON;BEATTY, THOMAS G.;LIN, BRIAN;ZHAO, MING;GARDNER, PAUL;FALCO, EMILIO;CRISWELL, STEPHEN;NAVA, CHANTANELLE;ROBINSON, CONNOR;HEDRICK, RICHARD;IVARSEN, KEVIN;HJELSTROM, ANNIE;VERA, JON DE;SZENTGYORGYI, ANDREW
    • Publications of The Korean Astronomical Society
    • /
    • v.30 no.2
    • /
    • pp.665-669
    • /
    • 2015
  • The Kepler mission has shown that small planets are extremely common. It is likely that nearly every star in the sky hosts at least one rocky planet. We just need to look hard enough-but this requires vast amounts of telescope time. MINERVA (MINiature Exoplanet Radial Velocity Array) is a dedicated exoplanet observatory with the primary goal of discovering rocky, Earth-like planets orbiting in the habitable zone of bright, nearby stars. The MINERVA team is a collaboration among UNSW Australia, Harvard-Smithsonian Center for Astrophysics, Penn State University, University of Montana, and the California Institute of Technology. The four-telescope MINERVA array will be sited at the F.L. Whipple Observatory on Mt Hopkins in Arizona, USA. Full science operations will begin in mid-2015 with all four telescopes and a stabilised spectrograph capable of high-precision Doppler velocity measurements. We will observe ~100 of the nearest, brightest, Sun-like stars every night for at least five years. Detailed simulations of the target list and survey strategy lead us to expect $15{\pm}4$ new low-mass planets.

Continuous Production of Authentic Human Growth Hormone from Methionyl Human Growth Hormone Using the Column Reactor of Immobilized Aminopeptidase M (고정화 Aminopeptidase M 컬럼 반응기를 이용한 메치오닐 인간성장호르몬으로부터 천연형 인간성장호르몬의 연속생산)

  • 이성희;김기태
    • KSBB Journal
    • /
    • v.10 no.3
    • /
    • pp.283-291
    • /
    • 1995
  • The characteristics of aminopeptidase M(ApM) immobilized covalently on Cellufine Formyl and the continuous production of authentic human growth hormone(hGH) from methionyl human growth hormono(met-hGH) using the column reactor packed with immobilized ApM were investigated. Immobilized ApM with the proportion of 2.3mg ApM per 1g Cellufine Formyl gel had the highest met-hGH conversion activity. The optimum pH(7.0) and temperature($55^{\circ}C$) showed no appreciable difference between free and immobilized enzymes and the optimum temperature in continuous operation of the column reactor was also found to be $55^{\circ}C$. Under the conditions at which met-hGH was converted completely to hGH, the yield and productivity were about 77% and 0.8mg hGH/ml$.$h, respectively. In two column reactors of different sizes, met-hGH was converted to hGH with the same conversion rates and hGH yields at the same space velocities. The half-life of the reactor systems at $45^{\circ}C$ and $55^{\circ}C$ were projected from the continuous operations for 90 days to be 225 days and 81 days, respectively.

  • PDF

Dynamics and die design in continuous and patch slot coating processes (Continuous 와 pattern slot 코팅 공정에서의 유동특성과 다이 설계)

  • Kim Su-Yeon;Shim Seo-Hoon;Shin Dong-Myeong;Lee Joo-Sung;Jung Hyun-Wook;Hyun Jae-Chun
    • Proceedings of the Korean Society of Rheology Conference
    • /
    • 2006.06a
    • /
    • pp.81-84
    • /
    • 2006
  • Slot coating process, in continuous and patch modes, has been applied for the many precise coating products, e.g., flat panel displays and second batteries. However, manufacturing uniform coating products is not a trivial task at high-speed operations because various flow instabilities or defects such as leaking, bubbles, ribbing, and rivulets are frequently observed in this process. It is no wonder, therefore, that many efforts to understand the various aspects of dynamics and coating windows of this process have been made both in academia and industry. In this study, as the first topic, flow dynamics within the coating bead in slot coating process has been investigated using the one-dimensional viscocapillary model by lubrication approximation and two-dimensional model by Flow-3D software. Especially, operability windows in both 1D and 2D cases with various slot die lip designs have been successfully portrayed. Also, effects of process conditions like viscosity and coating gap size on slot coating window have been analyzed. Also, some experiments to find minimum coating thickness and coating windows have been conducted using slot die coater implemented with flow visualization device, corroborating the numerical results. As the second topic, flow dynamics of both Newtonian and Non-Newtonian fluids in patch or pattern slot coating process, which is employed in manufacturing IT products such as secondary batteries, has been investigated for the purpose of optimal process designs. As a matter of fact, the flow control in this system is more difficult than in continuous case because od its transient or time-dependent nature. The internal die and die lip designs for patterned uniform coating products have been obtained by controlling flow behaviors of coating liquids issuing from slot. Numerical simulations have been performed using Fluent and Flow-3D packages. Flow behavior and pressure distribution inside the slot die has been compared with various die internal shapes and geometries. In the coating bead region, efforts to reduce irregular coating defects in head and tail parts of one patterned coating unit have been tried by changing die lip shapes. It has been concluded that optimal die internal design gas been developed, guaranteeing uniform velocity distribution of both Newtonian and shear thinning fluids at the die exit. And also optimal die lip design has been established, providing the longer uniform coating layer thickness within one coating unit.

  • PDF

Development of an Image Processing System for the Large Size High Resolution Satellite Images (대용량 고해상 위성영상처리 시스템 개발)

  • 김경옥;양영규;안충현
    • Korean Journal of Remote Sensing
    • /
    • v.14 no.4
    • /
    • pp.376-391
    • /
    • 1998
  • Images from satellites will have 1 to 3 meter ground resolution and will be very useful for analyzing current status of earth surface. An image processing system named GeoWatch with more intelligent image processing algorithms has been designed and implemented to support the detailed analysis of the land surface using high-resolution satellite imagery. The GeoWatch is a valuable tool for satellite image processing such as digitizing, geometric correction using ground control points, interactive enhancement, various transforms, arithmetic operations, calculating vegetation indices. It can be used for investigating various facts such as the change detection, land cover classification, capacity estimation of the industrial complex, urban information extraction, etc. using more intelligent analysis method with a variety of visual techniques. The strong points of this system are flexible algorithm-save-method for efficient handling of large size images (e.g. full scenes), automatic menu generation and powerful visual programming environment. Most of the existing image processing systems use general graphic user interfaces. In this paper we adopted visual program language for remotely sensed image processing for its powerful programmability and ease of use. This system is an integrated raster/vector analysis system and equipped with many useful functions such as vector overlay, flight simulation, 3D display, and object modeling techniques, etc. In addition to the modules for image and digital signal processing, the system provides many other utilities such as a toolbox and an interactive image editor. This paper also presents several cases of image analysis methods with AI (Artificial Intelligent) technique and design concept for visual programming environment.

Analysis of Future Demand and Utilization of the Urban Meteorological Data for the Smart City (스마트시티를 위한 도시기상자료의 미래수요 및 활용가치 분석)

  • Kim, Seong-Gon;Kim, Seung Hee;Lim, Chul-Hee;Na, Seong-Kyun;Park, Sang Seo;Kim, Jaemin;Lee, Yun Gon
    • Atmosphere
    • /
    • v.31 no.2
    • /
    • pp.241-249
    • /
    • 2021
  • A smart city utilizes data collected from various sensors through the internet of things (IoT) and improves city operations across the urban area. Recently substantial research is underway to examine all aspects of data that requires for the smart city operation. Atmospheric data are an essential component for successful smart city implementation, including Urban Air Mobility (UAM), infrastructure planning, safety and convenience, and traffic management. Unfortunately, the current level of conventional atmospheric data does not meet the needs of the new city concept. New and innovative approaches to developing high spatiotemporal resolution of observational and modeling data, resolving the complex urban structure, are expected to support the future needs. The geographic information system (GIS) integrates the atmospheric data with the urban structure and offers information system enhancement. In this study we proposed the necessity and applicability of the high resolution urban meteorological dataset based on heavy fog cases in the smart city region (e.g., Sejong and Pusan) in Korea.

An analysis of operation status depending on the characteristics of R&D projects in Sciences and Engineering universities (이공계 대학 연구과제 특성 별 운영 형태 현황)

  • Lee, Sang-Soog;Yoo, Inhyeok;Kim, Jinhee
    • Journal of Digital Convergence
    • /
    • v.20 no.4
    • /
    • pp.93-100
    • /
    • 2022
  • This study aimed to understand the current status of science and engineering university(SEU) R&D operations depending on the research project characteristics(e.g., stages and characteristics), then provide implications for future university R&D support systems and related policies. Hence, an online survey targeting SEU R&D recipients was conducted between October 4th to November 5th, 2021. Analyzing 445 valid data using the Apriori algorithm, 16 association rules for R&D operation according to the research project characteristics show that regardless of research characteristics, SEU's R&D projects, particularly in applied research, were funded or operated under the leadership of government or public institutions. For basic research, individual researchers had a higher level of autonomy in determining research topics; yet, they had a short duration (3 years) and a unit of evaluation period of more than 3 years. These findings can be empirical evidence for revealing the relationship among various variables in operating SEUs' R&D.

도시지역 고정식 신호체계의 효율적 운영 ( The Efficient Operations of the Pretimed Signal System ( PSS ) in Urban Area )

  • Kim, T.G.
    • Journal of Korean Port Research
    • /
    • v.10 no.2
    • /
    • pp.91-101
    • /
    • 1996
  • Today transportation problems are severer with the increase of the vehicles and travel demand in urban areas, but could not be completely solved with only the expansion of the new transportation facilities. Because the expansion of the new transportation facilities are limited in urban areas. As one of the Transportation System Management(TSM) techniques in this study, the simulation results of the existing signal systems which were operated based upon the peak time periods for increasing the efficiency on the pretimed signalized intersections(PSI) during the different time periods : the AM on-Peak, the AM off-Peak, the PM off-Peak, and the PM on-Peak, were as follows : i) There was no distinct difference in the total traffic volumes concentrated on the signalized intersections during the different time periods, but a considerably big difference in the directional traffic volumes for those time periods. ii) There were about 53% reduction of the average delay and 51% reduction of the fuel consumption when applying the different signal systems to the different time periods regardless of the CBD and Non-CBD. iii) There were about 36% increase of the average delay and 33% increase of the fuel consumption when applying the same signal systems during the peak time periods to the different time periods regardless of the CBD and Non-CBD. Based on the above results, it was concluded that constructing the different signal systems for the different time periods would be better than construction the same ones for those periods on the pretimed signalized intersections in urban areas.

  • PDF

Clinical course and prognosis of hemodynamically significant congenital heart defects in very low birth weight infants (혈역학적으로 의미있는 선천성 심기형을 가진 극소 저체중 출생아의 임상경과 및 예후)

  • Yoo, Hye Soo;Kim, Ji Eun;Park, Soo Kyoung;Seo, Hyun Ju;Jeong, Yoo Jin;Chio, Seo Heui;Jeong, Soo In;Kim, Sung Hoon;Yang, Ji Hyuk;Huh, June;Chang, Yun Sil;Jun, Tae Gook;Kang, I Seok;Park, Won Soon;Park, Pyo Won;Lee, Heung Jae
    • Clinical and Experimental Pediatrics
    • /
    • v.52 no.4
    • /
    • pp.481-487
    • /
    • 2009
  • Purpose : This study investigated the clinical course and prognostic factor of very low birth weight infants (VLBWI) with hemodynamically significant congenital heart defects (CHDs). Methods : Medical records of 1,098 VLBWI with birth weight <1,500 g who had been admitted to the neonatal intensive care unit of Samsung Medical Center from October 1994 to December 2007 were reviewed retrospectively. The data for these patients with hemodynamically significant CHD (n=33) were compared with those without CHD (n=1,065). Results : The incidence of CHD was 3.0% (33 patients) 7 patients (21%) had CHD combined with the congenital abnormalities or chromosomal disorders. The most common CHD was a ventricular septal defect. The incidence of intrauterine growth retardation was higher in patients with CHD than in patients without CHD (34% vs. 20%), but there were no significant differences in gestational age, birth weight, respiratory distress syndrome, bronchopulmonary dysplasia, necrotizing enterocolitis, severe intraventricular hemorrhage (${\geq}$Gr III), and periventricular leukomalacia. Cardiac surgery was performed on 13 patients (39%). Nine patients received staged operations, and 10 patients received early intervention. The overall mortality in patients who had CHD was higher than in the patients who did not have CHD (27% vs. 16%). In patients with CHD, congenital abnormalities or chromosomal disorders were more important factors for increased mortality (86% vs. 11%) than the degree of complexity of CHD (19% vs. 42%). Conclusion : The most important prognostic factors of VLBWI with CHD are the associated congenital abnormalities or chromosomal disorders.

Using the METHONTOLOGY Approach to a Graduation Screen Ontology Development: An Experiential Investigation of the METHONTOLOGY Framework

  • Park, Jin-Soo;Sung, Ki-Moon;Moon, Se-Won
    • Asia pacific journal of information systems
    • /
    • v.20 no.2
    • /
    • pp.125-155
    • /
    • 2010
  • Ontologies have been adopted in various business and scientific communities as a key component of the Semantic Web. Despite the increasing importance of ontologies, ontology developers still perceive construction tasks as a challenge. A clearly defined and well-structured methodology can reduce the time required to develop an ontology and increase the probability of success of a project. However, no reliable knowledge-engineering methodology for ontology development currently exists; every methodology has been tailored toward the development of a particular ontology. In this study, we developed a Graduation Screen Ontology (GSO). The graduation screen domain was chosen for the several reasons. First, the graduation screen process is a complicated task requiring a complex reasoning process. Second, GSO may be reused for other universities because the graduation screen process is similar for most universities. Finally, GSO can be built within a given period because the size of the selected domain is reasonable. No standard ontology development methodology exists; thus, one of the existing ontology development methodologies had to be chosen. The most important considerations for selecting the ontology development methodology of GSO included whether it can be applied to a new domain; whether it covers a broader set of development tasks; and whether it gives sufficient explanation of each development task. We evaluated various ontology development methodologies based on the evaluation framework proposed by G$\acute{o}$mez-P$\acute{e}$rez et al. We concluded that METHONTOLOGY was the most applicable to the building of GSO for this study. METHONTOLOGY was derived from the experience of developing Chemical Ontology at the Polytechnic University of Madrid by Fern$\acute{a}$ndez-L$\acute{o}$pez et al. and is regarded as the most mature ontology development methodology. METHONTOLOGY describes a very detailed approach for building an ontology under a centralized development environment at the conceptual level. This methodology consists of three broad processes, with each process containing specific sub-processes: management (scheduling, control, and quality assurance); development (specification, conceptualization, formalization, implementation, and maintenance); and support process (knowledge acquisition, evaluation, documentation, configuration management, and integration). An ontology development language and ontology development tool for GSO construction also had to be selected. We adopted OWL-DL as the ontology development language. OWL was selected because of its computational quality of consistency in checking and classification, which is crucial in developing coherent and useful ontological models for very complex domains. In addition, Protege-OWL was chosen for an ontology development tool because it is supported by METHONTOLOGY and is widely used because of its platform-independent characteristics. Based on the GSO development experience of the researchers, some issues relating to the METHONTOLOGY, OWL-DL, and Prot$\acute{e}$g$\acute{e}$-OWL were identified. We focused on presenting drawbacks of METHONTOLOGY and discussing how each weakness could be addressed. First, METHONTOLOGY insists that domain experts who do not have ontology construction experience can easily build ontologies. However, it is still difficult for these domain experts to develop a sophisticated ontology, especially if they have insufficient background knowledge related to the ontology. Second, METHONTOLOGY does not include a development stage called the "feasibility study." This pre-development stage helps developers ensure not only that a planned ontology is necessary and sufficiently valuable to begin an ontology building project, but also to determine whether the project will be successful. Third, METHONTOLOGY excludes an explanation on the use and integration of existing ontologies. If an additional stage for considering reuse is introduced, developers might share benefits of reuse. Fourth, METHONTOLOGY fails to address the importance of collaboration. This methodology needs to explain the allocation of specific tasks to different developer groups, and how to combine these tasks once specific given jobs are completed. Fifth, METHONTOLOGY fails to suggest the methods and techniques applied in the conceptualization stage sufficiently. Introducing methods of concept extraction from multiple informal sources or methods of identifying relations may enhance the quality of ontologies. Sixth, METHONTOLOGY does not provide an evaluation process to confirm whether WebODE perfectly transforms a conceptual ontology into a formal ontology. It also does not guarantee whether the outcomes of the conceptualization stage are completely reflected in the implementation stage. Seventh, METHONTOLOGY needs to add criteria for user evaluation of the actual use of the constructed ontology under user environments. Eighth, although METHONTOLOGY allows continual knowledge acquisition while working on the ontology development process, consistent updates can be difficult for developers. Ninth, METHONTOLOGY demands that developers complete various documents during the conceptualization stage; thus, it can be considered a heavy methodology. Adopting an agile methodology will result in reinforcing active communication among developers and reducing the burden of documentation completion. Finally, this study concludes with contributions and practical implications. No previous research has addressed issues related to METHONTOLOGY from empirical experiences; this study is an initial attempt. In addition, several lessons learned from the development experience are discussed. This study also affords some insights for ontology methodology researchers who want to design a more advanced ontology development methodology.

Study on the Travel and Tractive Characteristics of The Two-Wheel Tractor on the General Slope Ground (II)-Dynamic Side-overturn of the Tiller-trailer System- (동력경운기의 경사지견인 및 주행특성에 관한 연구 (II)-동력경운기-트레일러계의 욍골동 및 동횡전도한계)

  • 송현갑;정창주
    • Journal of Biosystems Engineering
    • /
    • v.3 no.1
    • /
    • pp.1-19
    • /
    • 1978
  • Power tiller is a major unit of agricultural machinery being used on farms in Korea. About 180.000 units are introduced by 1977 and the demand for power tiller is continuously increasing as the farm mechanization progress. Major farming operations done by power tiller are the tillage, pumping, spraying, threshing, and hauling by exchanging the corresponding implements. In addition to their use on a relatively mild slope ground at present, it is also expected that many of power tillers could be operated on much inclined land to be developed by upland enlargement programmed. Therefore, research should be undertaken to solve many problems related to an effective untilization of power tillers on slope ground. The major objective of this study was to find out the travelling and tractive characteristics of power tillers being operated on general slope ground.In order to find out the critical travelling velocity and stability limit of slope ground for the side sliding and the dynamic side overturn of the tiller and tiller-trailer system, the mathematical model was developed based on a simplified physical model. The results analyzed through the model may be summarized as follows; (1) In case of no collision with an obstacle on ground, the equation of the dynamic side overturn developed was: $$\sum_n^{i=1}W_ia_s(cos\alpha cos\phi-{\frac {C_1V^2sin\phi}{gRcos\beta})-I_{AB}\frac {v^2}{Rr}}=0$$ In case of collision with an obstacle on ground, the equation was: $$\sum_n^{i=1}W_ia_s\{cos\alpha(1-sin\phi_1)-{\frac {C_1V^2sin\phi}{gRcos\beta}\}-\frac {1}{2}I_{TP} \( {\frac {2kV_2} {d_1+d_2}\)-I_{AB}{\frac{V^2}{Rr}} \( \frac {\pi}{2}-\frac {\pi}{180}\phi_2 \} = 0 $$ (2) As the angle of steering direction was increased, the critical travelling veloc\ulcornerities of side sliding and dynamic side overturn were decreased. (3) The critical travelling velocity was influenced by both the side slope angle .and the direct angle. In case of no collision with an obstacle, the critical velocity $V_c$ was 2.76-4.83m/sec at $\alpha=0^\circ$, $\beta=20^\circ$ ; and in case of collision with an obstacle, the critical velocity $V_{cc}$ was 1.39-1.5m/sec at $\alpha=0^\circ$, $\beta=20^\circ$ (4) In case of no collision with an obstacle, the dynamic side overturn was stimu\ulcornerlated by the carrying load but in case of collision with an obstacle, the danger of the dynamic side overturn was decreased by the carrying load. (5) When the system travels downward with the first set of high speed the limit {)f slope angle of side sliding was $\beta=5^\circ-10^\circ$ and when travels upward with the first set of high speed, the limit of angle of side sliding was $\beta=10^\circ-17.4^\circ$ (6) In case of running downward with the first set of high speed and collision with an obstacle, the limit of slope angle of the dynamic side overturn was = $12^\circ-17^\circ$ and in case of running upward with the first set of high speed and collision <>f upper wheels with an obstacle, the limit of slope angle of dynamic side overturn collision of upper wheels against an obstacle was $\beta=22^\circ-33^\circ$ at $\alpha=0^\circ -17.4^\circ$, respectively. (7) In case of running up and downward with the first set of high speed and no collision with an obstacle, the limit of slope angle of dynamic side overturn was $\beta=30^\circ-35^\circ$ (8) When the power tiller without implement attached travels up and down on the general slope ground with first set of high speed, the limit of slope angle of dynamic side overturn was $\beta=32^\circ-39^\circ$ in case of no collision with an obstacle, and $\beta=11^\circ-22^\circ$ in case of collision with an obstacle, respectively.

  • PDF