• Title/Summary/Keyword: Synthesizing

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Analysis of X-ray image qualities-accuracy of shape and clearness of image-using X-ray digital tomosynthesis

  • Roh, Young Jun;Kang, Sung Taek;Kim, Hyung Cheol;Kim, Sung-Kwon
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.572-576
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    • 1997
  • X-ray laminography and DT(digital tomosynthesis) that can form a cross-sectional image of 3-D objects promise to be good solutions for inspecting interior defects of industrial products. The major factors of the digital tomosynthesis that influence on the quality of x-ray cross-sectional images are also discussed. The quality of images acquired from the DT system varies according to image synthesizing methods, the number of images used in image synthesizing, and X-ray projection angles. In this paper, a new image synthesizing method named 'log-root method' is proposed to get clear and accurate cross-sectional images, which can reduce both artifact and blurring generated by materials out of focal plane. To evaluate the quality of cross-sectional images, two evaluating criteria: (1) shape accuracy and (2) clearness in the cross-sectional image are defined. Based on this criteria, a series of simulations were performed, and the results show the superiority of the new synthesizing method over the existing ones such as averaging and minimum method.

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Probabilistic Models for Local Patterns Analysis

  • Salim, Khiat;Hafida, Belbachir;Ahmed, Rahal Sid
    • Journal of Information Processing Systems
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    • v.10 no.1
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    • pp.145-161
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    • 2014
  • Recently, many large organizations have multiple data sources (MDS') distributed over different branches of an interstate company. Local patterns analysis has become an effective strategy for MDS mining in national and international organizations. It consists of mining different datasets in order to obtain frequent patterns, which are forwarded to a centralized place for global pattern analysis. Various synthesizing models [2,3,4,5,6,7,8,26] have been proposed to build global patterns from the forwarded patterns. It is desired that the synthesized rules from such forwarded patterns must closely match with the mono-mining results (i.e., the results that would be obtained if all of the databases are put together and mining has been done). When the pattern is present in the site, but fails to satisfy the minimum support threshold value, it is not allowed to take part in the pattern synthesizing process. Therefore, this process can lose some interesting patterns, which can help the decider to make the right decision. In such situations we propose the application of a probabilistic model in the synthesizing process. An adequate choice for a probabilistic model can improve the quality of patterns that have been discovered. In this paper, we perform a comprehensive study on various probabilistic models that can be applied in the synthesizing process and we choose and improve one of them that works to ameliorate the synthesizing results. Finally, some experiments are presented in public database in order to improve the efficiency of our proposed synthesizing method.

Analysis of X-ray image Qualities -accuracy of shape and clearness of image using X-ray digital tomosynthesis (디지털 영상 합성에 의한 X선 단층 영상의 형상 정확도와 선명도 분석)

  • Roh, Yeong-Jun;Cho, Hyung-Suck;Kim, Hyeong-Cheol;Kim, Sung-Kwon
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.5
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    • pp.558-567
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    • 1999
  • X-ray laminography and DT(digital tomosynthesis) that can form a cross-sectional image of 3-D objects promis to be good solutions for inspecting interior defects of industrial products. DT is a kind of laminography technique and the difference is in the fact that it synthesizes the several projected images by use of the digitized memory and computation. The quality of images acquired from the DT system varies according to image synthesizing methods, the number of images used in image synthesizing, and X-ray projection angles. In this paper, a new image synthesizing method named 'log-root method' is proposed to get clear and accurate cross-sectional images, which can reduce both artifact and blurring generated by materials out of focal plane. To evaluate the quality of cross-sectional images, two evaluating criteria : (1) shape accuracy and (2) clearness of the cross-sectional images are defined. Based on these criteria, a series of simulations are performed, and the results show the superiority of the new synthesizing method over the existing ones such as averaging and minimum methods.

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Size Control of PbS Colloidal Quantum Dots and Their Application to Photovoltaic Devices

  • Lee, Wonseok;Ryu, Ilhwan;Choi, Geunpyo;Yim, Sanggyu
    • Proceedings of the Korean Vacuum Society Conference
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    • 2015.08a
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    • pp.249.1-249.1
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    • 2015
  • Quantum dots (QDs) are attracting growing attention for photovoltaic device applications because of their unique electronic, optical and physical properties. Lead sulfide (PbS) QDs are one of the most widely studied materials for the devices and known to have size-tunable properties. In this context, we investigated the relationship between the size of PbS QDs and two synthesizing conditions, a concentration of ligand, oleic acid in this work, and injection temperature. The inverted colloidal quantum dot solar cells based on the heterojunction of n-type zinc oxide layer and p-type PbS QDs were also fabricated. The size of the QDs and cell properties were observed to depend on both the QD synthesizing conditions, and hence the overall efficiency of the cell could vary even though the size of QDs used was same. The QD synthesizing conditions were finally optimized for the maximum cell efficiency.

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Effects of Salt and Precursor pH on Synthesizing Behavior and Grain Morphology of Mullite in Aqueous System (수용성 매체에서 뮬라이트의 합성거동 및 입자형상에 미치는 염 및 전구체 pH의 영향)

  • Jung, Yeon-Gil;Lee, Jae-Ean;Shin, Young-Ill;Kim, Jae-Won;Jo, Chang-Yong
    • Korean Journal of Materials Research
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    • v.13 no.4
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    • pp.251-258
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    • 2003
  • The effects of the salt and the precursor pH on the synthesizing behavior and the morphology of mullite have been studied. Two kinds of mullite precursor sols were prepared by the dissolution of two kinds of salt (aluminum nitrate enneahydrate, Al($NO_3$)$_3$$9H_2$O; type I and aluminum sulfate 14∼18 water, (SO$Al_4$)$_3$$\cdot$$14∼18H_2$O; type II) into the mixture of colloidal silica sol, respectively. Precursor pH of the sols was controlled to the acidic (pH= 1.5∼2) and basic (pH= 8.5∼9) conditions. The co-products with nitrate and sulfate were completely eliminated at $500^{\circ}C$ and $850^{\circ}C$, respectively, which was confirmed by TG/DTA results. The synthesizing temperature of mullite phase was found to be above $1200^{\circ}C$ for pH= 1.5∼2 and above $1300^{\circ}C$ for pH= 8.5∼9 in type I. However, in type II, the synthesizing temperature of mullite was decreased to $850^{\circ}C$ for pH= 1.5∼2 and $1100^{\circ}C$ for pH= 8.5∼9. The grain size of the mullite synthesized at pH= 8.5∼9 was larger than that at pH= 1.5∼2 in overall heat-treated temperatures, showing smaller grain size in type II. Aspect ratio of the mullite grains was more increased at pH= 1.5∼2 than pH= 8.5∼9 in type I, showing similar aspect ratio at both pH conditions in type II. It was found that the synthesizing temperature and grain size were predominantly governed by the initial precursor pH and decomposition of the salt, with minor effect on the grain morphology.

A Study on the Ge Substituted LAS Ceramics Using Metla Alkoxide (금속알콕사이드를 이용한 LAS계 내열세라믹스의 제조시 Ge 성분의 치환에 관한 연구)

  • 장성중;김형태;이응상
    • Journal of the Korean Ceramic Society
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    • v.32 no.11
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    • pp.1233-1240
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    • 1995
  • LAS system, which is difficult to be sintered, was densified by using the powder synthesized from metal alkoxides. Sinterability, thermal and mechanical properties were improved through synthesizing the complex oxide powder from the addition of Ge as an alkoxide. As a result, the synthesizing and sintering temperature of the LAS system lowered by about 10$0^{\circ}C$ and its modulus of rupture (MOR) increased twice higher compared to the sample from the oxide by the direct method.

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Scenario-based 3D Objects Synthesizing System Design

  • Nam, Ji-Seung;Gao, Hui;Kang, Mi-Young;Kim, Kyoung-Tae;Son, Seung-Chul;Pom, Chung-Ung;Heo, Kwon
    • Journal of Information Processing Systems
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    • v.2 no.1
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    • pp.18-22
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    • 2006
  • This paper proposes the framework of the scenario-based 3D image synthesizing system that allows common users who envision a scenario in their mind to realize it into the segments of cool animation. We focused on utilization of the existing motions to synthesize new motions for the objects. The framework is useful to build a 3D animation in game programming with a limited set of 3D objects. We also propose a practical algorithm to reuse and expand the objects. This algorithm is based on motion path modification rules. Both linear and nonlinear curve-fitting algorithms were applied to modify an animation by key frame interpolation and to make the motion appear realistic.

Synthesizing Intermediate Images Using Stereoscopic Images

  • Kwak, Ji-Hyun;Komar, V.S.V.;Kim, Kyung-Tae
    • Journal of the Optical Society of Korea
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    • v.6 no.4
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    • pp.143-149
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    • 2002
  • In this paper, we present an algorithm for synthesizing intermediate views from a stereoscopic pair of images. Syntheses of intermediate images allows one to realize a more comfortable the 3D display system. The proposed method is based on block matching, which is not ordinarily used. The contour information is used for a block decision. In order to find an equivalent (or corresponding) block, there are two steps: "matching of contour-to-original image" and "matching of contour-to-contour image" methods. "Matching of contour-to-contour image" uses both left and right contour images. This block matching method allows us to find the corresponding block in spite of different block sizes. Experimental results illustrate the performance of the proposed technique and we obtained a high quality image of more than 31 dB PSNR.image of more than 31 dB PSNR.

The Effect of Acetic Acid in Synthesizing PbSe Quantum Dots by Hot Solution Chemical Process (고온 열분해 반응법을 이용한 PbSe 나노입자의 Acetic Acid 첨가에 대한 영향)

  • Baek, In-Chan;Seok, Sang-Il;Chung, Yong-Chae
    • Journal of the Korean Ceramic Society
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    • v.44 no.2 s.297
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    • pp.89-92
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    • 2007
  • PbSe, with a band gap in the mid-infrared and a samll effective mass, is an interesting material for optical and electrical applications in infrared region. Various colloidal synthetic routes for synthesizing PbSe quantum dot nanoparticles have been developed in the last couple of years. In this work, stable colloidal solutions containing crystalline PbSe particles in the order of 5-15 nm were synthesized using different amount of acetic acid in high boiling coordinating solvents. The size and shape of PbSe nanoparticles was greatly influenced by coexistence of acetic acid in synthetic medium. It was observed by TEM that the shape of PbSe nanoparticles with different amount of acetic acid was changed from spherical to cube or star types.