• 제목/요약/키워드: Filling gaps

검색결과 47건 처리시간 0.024초

분해모델과 구멍 메움 알고리즘을 이용한 냉장고 내부 용적의 자동 계산 (Automatic Calculation of Interior Volume of Refrigerator by Hole Filling Algorithm)

  • 박래성;;정융호;박민근
    • 한국CDE학회논문집
    • /
    • 제22권1호
    • /
    • pp.59-69
    • /
    • 2017
  • Internal capacity of a refrigerator is an important indicator for design and purchasing criteria. The components facing the internal space may have holes or gaps between parts. In traditional way, design engineers manually remodeled the parts to fill the holes and the gaps for enclosed boundary of the internal space. Then they calculated internal volume by subtracting the assembly of parts from its enclosing volume. However, filling holes and gaps is not an automated process requiring a plenty of labor and time. In this research, we have developed a voxel-based method to estimate the internal volume of a refrigerator automatically. It starts transforming all components facing the interior space into voxels and fills all holes and gaps automatically by the developed hole-filling algorithm to form a completely closed boundary of the assembly. Then, it identifies the boundary voxels that are facing to the internal voxels with any part of the component. After getting the intersection points between the boundary voxels and the surfaces of components, it generates the boundary surface of triangular facets with the intersection points. Finally, it estimates the internal volume by adding volume of each tetrahedron composed of a triangle of boundary surface and an arbitrary point.

Reconstruction of In-beam PET for Carbon therapy with prior-knowledge of carbon beam-track

  • Kim, Kwangdon;Bae, Seungbin;Lee, Kisung;Chung, Yonghyun;An, Sujung;Joung, Jinhun
    • IEIE Transactions on Smart Processing and Computing
    • /
    • 제4권6호
    • /
    • pp.384-390
    • /
    • 2015
  • There are two main artifacts in reconstructed images from in-beam positron emission tomography (PET). Unlike generic PET, in-beam PET uses the annihilation photons that occur during heavy ion therapy. Therefore, the geometry of in-beam PET is not a full ring, but a partial ring that has one or two openings around the rings in order for the hadrons to arrive at the tumor without prevention of detector blocks. This causes truncation in the projection data due to an absence of detector modules in the openings. The other is a ring artifact caused by the gaps between detector modules also found in generic PET. To sum up, in-beam PET has two kinds of gap: openings for hadrons, and gaps between the modules. We acquired three types of simulation results from a PET system: full-ring, C-ring and dual head. In this study, we aim to compensate for the artifacts that come from the two types of gap. In the case of truncation, we propose a method that uses prior knowledge of the location where annihilations occur, and we applied the discrete-cosine transform (DCT) gap-filling method proposed by Tuna et al. for inter-detector gap.

DNN-based LTE Signal Propagation Modelling for Positioning Fingerprint DB Generation

  • Kwon, Jae Uk;Cho, Seong Yun
    • Journal of Positioning, Navigation, and Timing
    • /
    • 제10권1호
    • /
    • pp.55-66
    • /
    • 2021
  • In this paper, we propose a signal propagation modeling technique for generating a positioning fingerprint DB based on Long Term Evolution (LTE) signals. When a DB is created based on the location-based signal information collected in an urban area, gaps in the DB due to uncollected areas occur. The spatial interpolation method for filling the gaps has limitations. In addition, the existing gap filling technique through signal propagation modeling does not reflect the signal attenuation characteristics according to directions occurring in urban areas by considering only the signal attenuation characteristics according to distance. To solve this problem, this paper proposes a Deep Neural Network (DNN)-based signal propagation functionalization technique that considers distance and direction together. To verify the performance of this technique, an experiment was conducted in Seocho-gu, Seoul. Based on the acquired signals, signal propagation characteristics were modeled for each method, and Root Mean Squared Errors (RMSE) was calculated using the verification data to perform comparative analysis. As a result, it was shown that the proposed technique is improved by about 4.284 dBm compared to the existing signal propagation model. Through this, it can be confirmed that the DNN-based signal propagation model proposed in this paper is excellent in performance, and it is expected that the positioning performance will be improved based on the fingerprint DB generated through it.

기상드론 바람관측자료의 정확도 확보를 통한 대기하층 시공간 관측공백 해소 연구 (A Study on Filling the Spatio-temporal Observation Gaps in the Lower Atmosphere by Guaranteeing the Accuracy of Wind Observation Data from a Meteorological Drone)

  • 이승협;박미은;전혜림;박미르
    • 대기
    • /
    • 제33권5호
    • /
    • pp.441-456
    • /
    • 2023
  • The mobile observation method, in which a meteorological drone observes while ascending, can observe the vertical profile of wind at 1 m-interval. In addition, since continuous flights are possible at time intervals of less than 30 minutes, high-resolution observation data can be obtained both spatially and temporally. In this study, we verify the accuracy of mobile observation data from meteorological drone (drone) and fill the spatio-temporal observation gaps in the lower atmosphere. To verify the accuracy of mobile observation data observed by drone, it was compared with rawinsonde observation data. The correlation coefficients between two equipment for a wind speed and direction were 0.89 and 0.91, and the root mean square errors were 0.7 m s-1 and 20.93°. Therefore, it was judged that the drone was suitable for observing vertical profile of the wind using mobile observation method. In addition, we attempted to resolve the observation gaps in the lower atmosphere. First, the vertical observation gaps of the wind profiler between the ground and the 150 m altitude could be resolved by wind observation data using the drone. Secondly, the temporal observation gaps between 3-hour interval in the rawinsonde was resolved through a drone observation case conducted in Taean-gun, Chungcheongnam-do on October 13, 2022. In this case, the drone mobile observation data every 30-minute intervals could observe the low-level jet more detail than the rawinsonde observation data. These results show that the mobile observation data of the drone can be used to fill the spatio-temporal observation gaps in the lower atmosphere.

SPOT 영상을 이용한 Landsat-7의 SLC-off 영상 복원 (Restoration of Landsat ETM+ SLC-off Gaps Using SPOT Image)

  • 김혜진;유기윤;김용일
    • 한국측량학회:학술대회논문집
    • /
    • 한국측량학회 2006년도 춘계학술발표회 논문집
    • /
    • pp.229-234
    • /
    • 2006
  • On May 31, 2003. Landsat 7 experienced an anomaly causing the Scan Line Corrector(SLC) to stop functioning normally. The SLC-off causes individual scan lines to alternately overlap and then leave large gaps at the edge of the Image. A many scientists with ongoing experience using ETM+ data evaluated the scientific usability and validity of Landsat 7 products containing the SLC anomaly The best reference scene for gap-filling is the other SLC-on Landsat scene that provide same resolution, few changes, and similar data acquisition. But receiving of Landsat imagery is not stable in Korea. So SPOT image can be another alternative solution because it is a steady-state multispectral satellite image as Landsat image. In this study, we filled the SLC-off gap s of 2, 3, 4 bands using SPOT image by a local regression technique, and assigned the optimum spectral value to gaps of 1, 5, 7 bands based on a spectral adjacency. Through this process, we could restore Landsat SLC-off image and evaluated the accuracy of the results.

  • PDF

기상화학증착 텅스텐 막질의 표면 형태에 관한 연구 (Studies on the Morphology of the CVD Tungsten Film)

  • 전동수;김선래;이성영;박영규;전영수
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2008년도 하계종합학술대회
    • /
    • pp.377-378
    • /
    • 2008
  • Morphology is one of important issues when developing a layer of CVD-W. we need to control the process more precisely that is filling gaps between BL(bit line)and DC(direct contact). Whereas we are facing to difficulties like not-filling contacts due to marginal problems in deposition and etching process. This paper is for investigating a method to resolve morphology problem with strengthening the condition of seasoning.

  • PDF

CENSUS AND ANALYSIS OF GALACTIC MOLECULAR CLOUDS

  • HOJAEV, A.S.
    • 천문학논총
    • /
    • 제30권2호
    • /
    • pp.107-108
    • /
    • 2015
  • In this project, all available databases of molecular and gas-dust clouds in the Galaxy were cross-identified by taking into account available properties, including position, angular dimensions, velocity, density, temperature and mass. An initial list of about 7000 entries was condensed into a cross-identified all-sky catalogue containing molecular and gas-dust clouds. Some relationships were studied between the main physical features of clouds. Finally, we prepared a complex observing program and address future work for filling in the gaps.

수종의 치과용 수복재료 및 시멘트의 radiopacity (RADIOPACITY OF DENTAL RESTORATIVE MATERIALS AND CEMENTS)

  • 양홍서;정현주;강병철;오원만
    • 치과방사선
    • /
    • 제24권1호
    • /
    • pp.59-66
    • /
    • 1994
  • The radiopacity of six composite resins, three resin luting cements and ten filling materials were studied. The purpose was to obtain an indication of radiopacity value of different brands within each of these groups of materials and to show differences in radiopacities of filling materials and natural tooth structures. On radiographs, the optimal densities of standardized samples were determined by computer imaging system and radiopacity values of the materials were expressed in millimeter equivalent aluminum. Within the groups of materials studied, there was considerable variation in radiopacity. The composite resins of P-50, Z100 and Prisma AP.H displayed much higher radiopacities than aluminum. Panavia resin cement was shown to be similarly radiopaque to aluminum. Generally, the radiopacity of base and filling materials appeared to be higher than that of the enamel and dentin. If materials with substantial difference in radiopacity are used in combined applications for restorative treatment of teeth, lower radiopacity can interfere with the diagnosis and detection of gaps near the restoration.

  • PDF

분해 모델을 이용한 자동차 차체의 틈새 탐색 시스템 개발 (Development of Gap Searching System for Car Body Assembly by Decomposition Model Representation)

  • 배원중;이승훈;박성배;정융호
    • 한국자동차공학회논문집
    • /
    • 제20권4호
    • /
    • pp.109-118
    • /
    • 2012
  • Large number of part design for aircraft and automobile is preceded by functional or sectional design groups for efficiency. However, interferences and gaps can be found when the parts and sub-assemblies by those design groups are to be assembled. These interferences and gaps cause design changes and additional repair processes. While interference problem has been resolved by digital mockup and concurrent engineering methodology, gap problem has been covered by temporary treatment of filling gap with sealant. This kind of fast fix causes fatal problem of leakage when the gap is too big for filling or the treatment gets old. With this research, we have developed a program to find the gap automatically among parts of assembly so that users can find them to correct their design before manufacturing stage. By using decomposition model representation method, the developed program can search the gap among complex car body parts to be visualized with volumetric information. It can also define the boundary between the gap and exterior empty space automatically. Though we have proved the efficiency of the developed program by applying to automobile assembly, application of the program is not limited to car body only, but also can be extended to aircraft and ship design of large number of parts.

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

  • 한낙현
    • 무역상무연구
    • /
    • 제46권
    • /
    • 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