• Title/Summary/Keyword: Gap-filling

Search Result 183, Processing Time 0.023 seconds

Spatial Gap-Filling of Hourly AOD Data from Himawari-8 Satellite Using DCT (Discrete Cosine Transform) and FMM (Fast Marching Method)

  • Youn, Youjeong;Kim, Seoyeon;Jeong, Yemin;Cho, Subin;Kang, Jonggu;Kim, Geunah;Lee, Yangwon
    • Korean Journal of Remote Sensing
    • /
    • v.37 no.4
    • /
    • pp.777-788
    • /
    • 2021
  • Since aerosol has a relatively short duration and significant spatial variation, satellite observations become more important for the spatially and temporally continuous quantification of aerosol. However, optical remote sensing has the disadvantage that it cannot detect AOD (Aerosol Optical Depth) for the regions covered by clouds or the regions with extremely high concentrations. Such missing values can increase the data uncertainty in the analyses of the Earth's environment. This paper presents a spatial gap-filling framework using a univariate statistical method such as DCT-PLS (Discrete Cosine Transform-based Penalized Least Square Regression) and FMM (Fast Matching Method) inpainting. We conducted a feasibility test for the hourly AOD product from AHI (Advanced Himawari Imager) between January 1 and December 31, 2019, and compared the accuracy statistics of the two spatial gap-filling methods. When the null-pixel area is not very large (null-pixel ratio < 0.6), the validation statistics of DCT-PLS and FMM techniques showed high accuracy of CC=0.988 (MAE=0.020) and CC=0.980 (MAE=0.028), respectively. Together with the AI-based gap-filling method using extra explanatory variables, the DCT-PLS and FMM techniques can be tested for the low-resolution images from the AMI (Advanced Meteorological Imager) of GK2A (Geostationary Korea Multi-purpose Satellite 2A), GEMS (Geostationary Environment Monitoring Spectrometer) and GOCI2 (Geostationary Ocean Color Imager) of GK2B (Geostationary Korea Multi-purpose Satellite 2B) and the high-resolution images from the CAS500 (Compact Advanced Satellite) series soon.

A Study on the Principles of Good Faith under International Transaction -Focused on the CISG- (국제거래상 신의성실의 원칙에 관한 연구 - CISG를 중심으로 -)

  • Han, Nak-Hyun
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
    • /
    • v.46
    • /
    • pp.61-104
    • /
    • 2010
  • The purpose of this work aims to analyse the principles of good faith under international transaction with CLOUT and UNILEX cases. Article 7(1) CISG sets the stage for the interpretation by promoting a uniform approach using good faith and the international charter of the convention. In other words, article 7(1) defines the purpose and the principle of interpretation and is applied to the Convention as a whole. As such, it also includes article 7(2), which goes beyond the big picture and settles the problems of gap filling. It is also important to understanding that the mandate of the CISG is to look for a solution, which is not only restricted to interpretation but extends to solving a problem. The problem in this work is to find out how gap filling is achieved and, because of the autonomous mandate of interpretation, to explain and understand its relationship with domestic law. The solution to the interpretation of article 7(2) must be found within the four corners of the CISG. To restate, article 7(2) describes two situations where gap filling is needed. First, if the matter is governed by the Convention but not expressly settled, then a gap must be filled in conformity with general principles on which it is based. Second, if the matter is not covered then the gap must be filled taking domestic law into consideration. There are two reasons why a matter may not be covered by the Convention. First and most obviously, it has been specifically exclude from the sphere of Application by the CISG itself, such as validity in article 4. Second, changes in business methods will lead to gaps. The United Nations has established a service known as CLOUT. This contains abstracts of hundreds of selected decisions of both courts and arbitration tribunals. And UNILEX is cosponsored by the Italian Centre for Comparative and Foreign Law Studies and UNIDROIT Contract Principles. The cases are in abstract format, but, when available, the full text of the case in the original language is also supplied.

  • PDF

A point-scale gap filling of the flux-tower data using the artificial neural network (인공신경망 기법을 이용한 청미천 유역 Flux tower 결측치 보정)

  • Jeon, Hyunho;Baik, Jongjin;Lee, Seulchan;Choi, Minha
    • Journal of Korea Water Resources Association
    • /
    • v.53 no.11
    • /
    • pp.929-938
    • /
    • 2020
  • In this study, we estimated missing evapotranspiration (ET) data at a eddy-covariance flux tower in the Cheongmicheon farmland site using the Artificial Neural Network (ANN). The ANN showed excellent performance in numerical analysis and is expanding in various fields. To evaluate the performance the ANN-based gap-filling, ET was calculated using the existing gap-filling methods of Mean Diagnostic Variation (MDV) and Food and Aggregation Organization Penman-Monteith (FAO-PM). Then ET was evaluated by time series method and statistical analysis (coefficient of determination, index of agreement (IOA), root mean squared error (RMSE) and mean absolute error (MAE). For the validation of each gap-filling model, we used 30 minutes of data in 2015. Of the 121 missing values, the ANN method showed the best performance by supplementing 70, 53 and 84 missing values, respectively, in the order of MDV, FAO-PM, and ANN methods. Analysis of the coefficient of determination (MDV, FAO-PM, and ANN methods followed by 0.673, 0.784, and 0.841, respectively.) and the IOA (The MDV, FAO-PM, and ANN methods followed by 0.899, 0.890, and 0.951 respectively.) indicated that, all three methods were highly correlated and considered to be fully utilized, and among them, ANN models showed the highest performance and suitability. Based on this study, it could be used more appropriately in the study of gap-filling method of flux tower data using machine learning method.

The Development of the Unfading Polyvinyl Butyral Gap-filling Material Based on Reversible Properties and Restoration of a Punchong Plate from Sam-cheon Temple Site with This Polyvinyl Butyral Product (가역성을 갖는 무황변 Polyvinyl Butyral 메움제의 개발과 이를 이용한 삼천사지 분청사기접시의 복원)

  • Han, Won-Sik;Wi, Koang-Chul;Park, Gi-Jung;Hong, Tae-Kee
    • Journal of Conservation Science
    • /
    • v.25 no.3
    • /
    • pp.293-298
    • /
    • 2009
  • We fabricated the gap-filling material for antic-ceramics restoration which were made up polyvinyl butyral (butvar) base and silane system additive in iso-propyl solvent. This was made hardness control possible that user want. And it have very strong adhesion and shear strength properties and is shown the best properties for pigment filling, anti-contractibility, coloring as like epoxy system materials. Particularly, the yellowing and ir-reversibility problem in Epoxy restoration material were finally steadiness. So, there is guarantee in the eternity and stabilization of restoration for antic-celamics. And in order to show the reversible state of the restoration, we successfully dissolve this polyvinyl butyral gap-filling materials in solvent after perfect restoring the Punchong plate from sam-chun temple site subsequently.

  • PDF

Long-gap Filling Method for the Coastal Monitoring Data (해양모니터링 자료의 장기결측 보충 기법)

  • Cho, Hong-Yeon;Lee, Gi-Seop;Lee, Uk-Jae
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.33 no.6
    • /
    • pp.333-344
    • /
    • 2021
  • Technique for the long-gap filling that occur frequently in ocean monitoring data is developed. The method estimates the unknown values of the long-gap by the summation of the estimated trend and selected residual components of the given missing intervals. The method was used to impute the data of the long-term missing interval of about 1 month, such as temperature and water temperature of the Ulleungdo ocean buoy data. The imputed data showed differences depending on the monitoring parameters, but it was found that the variation pattern was appropriately reproduced. Although this method causes bias and variance errors due to trend and residual components estimation, it was found that the bias error of statistical measure estimation due to long-term missing is greatly reduced. The mean, and the 90% confidence intervals of the gap-filling model's RMS errors are 0.93 and 0.35~1.95, respectively.

Effect of Plasma Pretreatment on Superconformal Cu Alloy Gap-Filling of Nano-scale Trenches

  • Mun, Hak-Gi;Lee, Jeong-Hun;Lee, Su-Jin;Yun, Jae-Hong;Kim, Hyeong-Jun;Lee, Nae-Eung
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2011.02a
    • /
    • pp.53-53
    • /
    • 2011
  • As the dimension of Cu interconnects has continued to reduce, its resistivity is expected to increase at the nanoscale due to increased surface and grain boundary scattering of electrons. To suppress increase of the resistivity in nanoscale interconnects, alloying Cu with other metal elements such as Al, Mn, and Ag is being considered to increase the mean free path of the drifting electrons. The formation of Al alloy with a slight amount of Cu broadly studied in the past. The study of Cu alloy including a very small Al fraction, by contrast, recently began. The formation of Cu-Al alloy is limited in wet chemical bath and was mainly conducted for fundamental studies by sputtering or evaporation system. However, these deposition methods have a limitation in production environment due to poor step coverage in nanoscale Cu metallization. In this work, gap-filling of Cu-Al alloy was conducted by cyclic MOCVD (metal organic chemical vapor deposition), followed by thermal annealing for alloying, which prevented an unwanted chemical reaction between Cu and Al precursors. To achieve filling the Cu-Al alloy into sub-100nm trench without overhang and void formation, furthermore, hydrogen plasma pretreatment of the trench pattern with Ru barrier layer was conducted in order to suppress of Cu nucleation and growth near the entrance area of the nano-scale trench by minimizing adsorption of metal precursors. As a result, superconformal gap-fill of Cu-Al alloy could be achieved successfully in the high aspect ration nanoscale trenches. Examined morphology, microstructure, chemical composition, and electrical properties of superfilled Cu-Al alloy will be discussed in detail.

  • PDF

Improvements of Pulse Doppler Gap Filling Algorithms for Portable Medical Ultrasound Imaging System (휴대용 초음파진단기를 위한 펄스 도플러 갭 필링 알고리즘의 개선)

  • Bae, MooHo;An, Hyung-Jun
    • The Journal of the Acoustical Society of Korea
    • /
    • v.31 no.8
    • /
    • pp.580-589
    • /
    • 2012
  • In this paper, we studied on Doppler gap-filling algorithms suitable for a portable or low-cost medical ultrasound imaging system, and as a result, found out algorithms based on mirroring or autoregressive model. Moreover, controlling the computational demand in the proper range, we improved the performances of these algorithms by solving their problems. Effectiveness of these modified algorithms is verified by computer simulations and experiments which used artificially generated Doppler signals and Doppler data acquired from human body through an actual ultrasound system.

Flowable oxide CVD Process for Shallow Trench Isolation in Silicon Semiconductor

  • Chung, Sung-Woong;Ahn, Sang-Tae;Sohn, Hyun-Chul;Lee, Sang-Don
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.4 no.1
    • /
    • pp.45-51
    • /
    • 2004
  • We have proposed a new shallow trench isolation (STI) process using flowable oxide (F-oxide) chemical vapor deposition (CVD) for DRAM application and it was successfully developed. The combination of F-oxide CVD and HDP CVD is thought to be the superior STI gap-filling process for next generation DRAM fabrication because F-oxide not only improves STI gap-filling capability, but also the reduced local stress by F-oxide in narrow trenches leads to decrease in junction leakage and gate induced drain leakage (GIDL) current. Finally, this process increased data retention time of DRAM compared to HDP STI. However, a serious failure occurred by symphonizing its structural dependency of deposited thickness with poor resistance against HF chemicals. It could be suppressed by reducing the flow time during F-oxide deposition. It was investigated collectively in terms of device yield. In conclusion, the combination of F-oxide and HDP oxide is the very promising technology for STI gap filling process of sub-100nm DRAM technology.

Experimental Study of Motion Behavior of Side-by-Side Moored Two Floating Bodies Including Sloshing in Head Sea (선수파 중 슬로싱을 고려한 병렬배치된 두 부유체의 거동 특성에 관한 실험 연구)

  • Cho, Seok-Kyu;Sung, Hong-Gun;Hong, Jang-Pyo;Hong, Sa-Young;Hong, Seok-Won
    • Journal of Ocean Engineering and Technology
    • /
    • v.26 no.6
    • /
    • pp.46-52
    • /
    • 2012
  • The motions and drift forces of side-by-side moored FSRU and LNGC including the sloshing effect, were studied using experiments. The FSRU and LNGC contained LNG cargo tanks and the LNG sloshing could affect the motions and drift forces of the structures due to its coupling with floating body motion. The effect of coupling can vary with the LNG filling level, and the effect of the filling level was investigated. The coupling effect was stronger at lower filling level. It was confirmed that longitudinal sloshing influenced the surge and surge mean drift force in head sea. In addition, gap flow affected the sway and mean drift forces. Sloshing attenuated the sway and yaw excited by gap flow in side-by-side configuration.

Flow Characteristics and Filling Time Estimation for Underfill Process (언더필 공정에 대한 유동 특성과 침투 시간 예측 연구)

  • Sim, Hyung-Sub;Lee, Seong-Hyuk;Kim, Jong-Min;Shin, Young-Eui
    • Journal of Welding and Joining
    • /
    • v.25 no.3
    • /
    • pp.45-50
    • /
    • 2007
  • The present study is devoted to investigate the transient flow and to estimate the filling time fur underfill process by using the numerical model established on the fluid momentum equation. For optimization of the design and selection of process parameters, this study extensively presents an estimation of the filling time in the view points of some important factors related to underfill materials and flip-chip geometry. From the results, we conclude that the filling time changes with respect to the under fill materials because of different viscosity, surface tension coefficient and contact angle. It reveals that, as the gap height increases, the filling time decreases substantially, and goes to the saturated values.