• Title/Summary/Keyword: FAGA

Search Result 5, Processing Time 0.02 seconds

Gravity-Geologic Prediction of Bathymetry in the Drake Passage, Antarctica (Gravity-Geologic Method를 이용한 남극 드레이크 해협의 해저지형 연구)

  • 김정우;도성재;윤순옥;남상헌;진영근
    • Economic and Environmental Geology
    • /
    • v.35 no.3
    • /
    • pp.273-284
    • /
    • 2002
  • The Gravity-Geologic Method (GGM) was implemented for bathymetric determinations in the Drake Passage, Antarctica, using global marine Free-air Gravity Anomalies (FAGA) data sets by Sandwell and Smith (1997) and local echo sounding measurements. Of the 6548 bathymetric sounding measurements, two thirds of these points were used as control depths, while the remaining values were used as checkpoints. A density contrast of 9.0 gm/㎤ was selected based on the checkpoints predictions with changes in the density contrast assumed between the seawater and ocean bottom topographic mass. Control depths from the echo soundings were used to determine regional gravity components that were removed from FAGA to estimate the gravity effects of the bathymetry. These gravity effects were converted to bathymetry by inversion. In particular, a selective merging technique was developed to effectively combine the echo sounding depths with the GGM bathymetiy to enhance high frequency components along the shipborne sounding tracklines. For the rugged bathymetry of the research area, the GGM bathymetry shows correlation coefficients (CC) of 0.91, 0.92, and 0.85 with local shipborne sounding by KORDI, GEODAS, and a global ETOPO5 model, respectively. The enhanced GGM by selective merging shows imploved CCs of 0.948 and 0.954 with GEODAS and Smith & Sandwell (1997)'s predictions with RMS differences of 449.8 and 441.3 meters. The global marine FAGA data sets and other bathymetric models ensure that the GGM can be used in conjunction with shipborne bathymetry from echo sounding to extend the coverage into the unmapped regions, which should generate better results than simply gridding the sparse data or relying upon lower resolution global data sets such as ETOPO5.

Delay optimization algorithm on FPGAs (FPGA 에 대한 지연시간 최적화 알고리듬)

  • Hur Chang-Wu;Kim Nam-Woo
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.10 no.7
    • /
    • pp.1259-1265
    • /
    • 2006
  • In this paper, we propose a combined synthetic algorithm of the logic level for high speed FPGA design. The algorithm divides critical path to reduce delay time and generates a circuit which the divided circuits execute simultaneously. This kernel selection algorithm is made by C-langage of SUN UNIX. We compare this with the existing FlowMap algorithm. This proposed algorithm shows result on 33.3% reduction of delay time by comparison with the existing algorithm.

The Three-Bite Technique: A Novel Method of Dog Ear Correction

  • Jaber, Omar;Vischio, Marta;Faga, Angela;Nicoletti, Giovanni
    • Archives of Plastic Surgery
    • /
    • v.42 no.2
    • /
    • pp.223-225
    • /
    • 2015
  • The closure of any circular or asymmetric wound can result in puckering or an excess of tissue known as a 'dog ear'. Understanding the mechanism of dog ear formation is a fundamental requirement necessary to facilitate an appropriate treatment. Many solutions have been reported in the literature, but in all cases, the correction entails the extension of the scar and the sacrifice of the dermal plexus. Here, we propose a novel technique of dog ear correction by using a three-bite suture that sequentially pierces the deep fascial plane and each dog ear's margin, thus allowing for flattening the dog ear by anchoring the over-projecting tissue to the deep plane. The three-bite technique proved to be a fast, easy, and versatile method of immediate dog ear correction without extending the scar, while maintaining a full and complete local skin blood supply.

Content-based Image Retrieval Using Fuzzy Multiple Attribute Relational Graph (퍼지 다중특성 관계 그래프를 이용한 내용기반 영상검색)

  • Jung, Sung-Hwan
    • The KIPS Transactions:PartB
    • /
    • v.8B no.5
    • /
    • pp.533-538
    • /
    • 2001
  • In this paper, we extend FARGs single mode attribute to multiple attributes for real image application and present a new CBIR using FMARG(Fuzzy Multiple Attribute Relational Graph), which can handle queries involving multiple attributes, not only object label, but also color, texture and spatial relation. In the experiment using the synthetic image database of 1,024 images and the natural image database of 1.026 images built from NETRA database and Corel Draw, the proposed approach shows 6~30% recall increase in the synthetic image database and a good performance, at the displacements and the retrieved number of similar images in the natural image database, compared with the single attribute approach.

  • PDF

Bathymetry Change Investigation of the 2011 Tohoku Earthquake

  • Kim, Kwang Bae;Lee, Chang Kyung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.33 no.3
    • /
    • pp.181-192
    • /
    • 2015
  • Bathymetry change due to the 2011 Tohoku (M9.0) earthquake was investigated through satellite altimetry-derived free-air gravity anomalies (SAFAGA) and shipborne measurements. The earthquake occurred at the plate boundaries near the northeastern coast of Japan, where the oceanic plate subducts beneath the continental plate along deep-sea trench. Data analyzed in this study include SAFAGA from Scripps Institution of Oceanography (SIO), shipborne bathymetry (SB) from the U.S. National Geophysical Data Center (NGDC) and the Japan Agency for Marine-Earth-Science And Technology (JAMSTEC). To estimate the bathymetry change, a reference bathymetry before the earthquake was predicted by gravity-geologic method (GGM) and Smith & Sandwell’s (SAS) method. In comparison with the bathymetry models before the earthquake, GGM bathymetry model generated by a tuning density contrast of 17.04 g/cm3 by downward continuation method was selected because it shows better bathymetry in the short wavelength below about 6 km. From the results, remarkable bathymetry change of about ±50 m was found on the west side of the Japan Trench caused by the earthquake.