• Title/Summary/Keyword: DirA

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Effect of Stuffing of TiN on the Diffusion Barrier Property(I) : Al/TiN/Si Structure (TiN의 충진처리가 확산방지막 특성에 미치는 영향(I) : Al/TiN/Si 구조)

  • Park, Gi-Cheol;Kim, Gi-Beom
    • Korean Journal of Materials Research
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    • v.5 no.1
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    • pp.87-95
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    • 1995
  • The effect of stuffing of TiN on the diffusion barrier property between A1 and Si was investigated. The stuffing of TiN was performed by annealing in a Nz ambient at $450^{\circ}C$ for 30min. By TEM analysis, it is identified that there are solid-free or open spaces of a b u t 10-20$\AA$ between the grains of asdeposited TiN. In the case of stuffed TiN, the width of solid-free or open spaces has been reduced to about 10$\AA$ or below. The combination of RBS and AES analyses showed that the asdeposited TiN had about 7at.% of oxygen, and that the stuffed TiN had about 10-15at.% of oxygen. The diffusion barrier test result shows that after annealing at $650^{\circ}C$ for lhour, the asdeposited TiN fails due to the formation of A1 spikes and Si pits in the Si substrate. However, in the case of stuffed TiN, there is no indication of Al spikes and Si pits at the same annealing condition. Thus, it is concluded that this stuffing of TiN significantly improves the diffusion barrier property of TiN between A1 and Si. It is considered that the stuffing effect results from the reduced diffusion through grain boundaries due to the reduced spacing of grain boundaries.

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Poisoning of the Ni/MgO Catalyst by Alkali Carbonates in a DIR-MCFC (용융탄산염 연료전지에서 알칼리 탄산염에 의한 Ni/MgO 촉매의 피독)

  • Moon, Hyeung-Dae;Kim, Joon-Hee;Ha, Heung Yong;Lim, Tae-Hoon;Hong, Sung-Ahn;Lee, Ho-In
    • Applied Chemistry for Engineering
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    • v.10 no.5
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    • pp.754-760
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    • 1999
  • The properties of the catalyst for a direct internal reforming type molten carbonate fuel cell were examined by ICP, BET, CHN, EDS, and $H_2$ chemisorption. Potassium and lithium, the components of carbonate electrolyte, were transported to the catalyst during the operation of fuel cell, and the amounts of the deposited alkali elements were reduced in the order of inlet, outlet, and the middle. From the direct correlation between the amount of alkali and the physical properties such as BET surface area and Ni dispersion, and from the observation of the lump of the alkali species on the poisoned catalyst, it was confirmed that the physical blocking of the catalyst by alkali deposition was the main reason for the deactivation. Although the amount of alkali species was greater at the inlet than at the oulet, the catalyst sampled from the outlet had lower activity. This was caused by the chemical interaction between the alkali species and the catalyst at the outlet where temperature was highest in the cell body, which was detected by FT-IR analyses.

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Biodegradation Characteristics of Poly-3-hydroxybutyrate, $Sky-Green^R$ and $Mater-Bi^R$ by Soil Bacteria (토양세균의 Poly-3-hydroxybutyrate,$Sky-Green^R$$Mater-Bi^R$분해 특성)

  • 이애리;김말남
    • Korean Journal of Microbiology
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    • v.36 no.4
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    • pp.299-305
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    • 2000
  • Degradation behavior of the three commercial biodegradable polymers, namely poly(3-hydroxybutyrate) (PHB) Sky-Green/sup R/ (SG) and Mater-Bi/sup R/ (MB) was investigated using bacteria isolated from activated sludge and farm soil. Three PHB degrading bacteria, three SG degrading bacteria and one MB degrading bacteria were isolated. The PHB degrading bacteria were identified to be Flavimonas oryzihabitans, Corynebacterium pseudodiphtheriticum and Micrococcus diversus, while Pseudomonas vesicuraris, Pasteurlla multocida and Flavobacterium odoratum were identified as SG degrading bacteria. As for MB, Pseudomonas vesicuraris was isolated. The shake flask test for 28 days indicated that the rate of biodegradation of PHB, SG and MB in terms of weight loss were about 44∼69% 25∼32% and 29% respectively. The surface morphology of PHB, SG andMB films before and after degradation by microorganisms in an activated sludge soil was observed under SEM, demonstrating that the film surface had a very porous structure, and that microorganisms colonized heavily on the film surface. TOC and pH variation as a result of abiotic hydrolysis, or microbial growth in the absence of the polymers were compared to those due to degradation by F. oryzihabitans. Abiotic hydrolysis of PHB was three times as fast as that of SG and MB. Addition of yeast extract to the basal liquid medium accelerated the biodegradation of the polymers. Biodegradation of PHB was always faster than that of SG and MB irrespectively of the presence of yeast extract in the basal liquid medium.

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A Survey Study on Public Health Nursing Manpower is Pusan, Kyung Nam area (부산.경남지역 보건간호 인력분포와 보건사업 제공 실태에 대한 조사연구)

  • Hwang, Bo-Sun;Bae, Jung-Ha;Kim, Bong-Im
    • Research in Community and Public Health Nursing
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    • v.1 no.1
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    • pp.107-114
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    • 1989
  • The purpose of this study was to investigate the Manpower status of nurse in the Health Centers from 1985 year to 1986 year, Pusu and Kyung Nam area. As the results through the analysis of collected data, the following conclusion has been reached. 1. The number of nurses who worked in the Family Planning in Pusan was largest and the number of nurses in Kyung Nam who worked for Consultation Clinic was the largest both in 1985 and in 1986. 2. Population per Health Center by year; Population per Health Center in Pusan area increased from 351,681 persons 1985 year to 357,884 persons, 1986 year In Kyung Nam area population per Health Center increased from 130,247 persons, 1985 to 130,252 persons,1986 year. 3. Population per Public Health Nurses by year; Population per PHN in Pusan area increased from 30,058 persons, 1985 to 31,120 persons, 1986. But in Kyung Nam area population per PHN decreased from 22,500 persons, 1985 to 16,747 persons, 1986. 4. Activities of Public Health Nurses by clinic; The order of priority activities by PHNs was family Planning in Pusan area and M.C.H in Kyung Nam area. 5. The target population per Public Health Nurse; The target population of M.C.H was the most in Pusan, 1985. In Kyung Nam area the most target population was M.C.H., 1985 year. 6. Number of service per Public Health Nurse; In number of service per PHN, the hightest health nursing service activity in Pusan and was M.C.H in Kyung Nam area.

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Accuracy of Hybrid Navigation System Combining Dead Reckoning and Loran C (추측항법과 Loran C항법을 결합한 Hybrid 항법의 정도)

  • Lee, Won-Woo;Sin, Hyeong-Il
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.20 no.2
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    • pp.105-111
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    • 1984
  • Recently, Hybrid Navigation Systems combining Omega, NNSS, Loran C and Dead reckoning etc. served to give us highly accurate ship's position, and a number of ships are equipped with these navigation systems. In order to evaluate for the accuracy of this navigation system observations of Loran C, 5970 and 9970 chains and Radar at the same time were made on board m.s Jeonbuk 401 and 403 training ships of Gunsan Fisheries Collage at nine stations in the yellow sea from July, 1982 to June, 1983, and then were done by the Hybrid Navigation System combining Dead reckoning and Loran C at the same areas. The authors investigated the accuracy of the Hybrid Navigation System based on measurements of the relative positional error which is defined as the difference between the position fixed by this system or the Loran C system, and the one by the Radar. The obtained results are as follows; 1. The mean standard deviation of the time difference of Loran C were about 0.21$\mu$s in 9970 chain and about 0.06$\mu$s in 5970 chain, and the fluctuation of the time difference of Loran C in 5970 chain was smaller than that in 9970 chain. 2. The positional error between two positions by Radar and the Hybrid Navigation System in 9970 chain was about 0.4 miles, and between two positions by Radar and Loran C was about 0.51 miles. The Hybrid Navigation System was therefore more accurate than Loran C System. 3. The positional error between two positions by Radar and Hybrid Navigation System in 5970 chain was about 0.4 miles, and between two positions by Radar and computer simulation of Loran C was about 0.98 miles. Consequently, Hybrid Navigation System was more accurate than computer simulation of Loran C system.

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4-Dimensional dose evaluation using deformable image registration in respiratory gated radiotherapy for lung cancer (폐암의 호흡동조방사선치료 시 변형영상정합을 이용한 4차원 선량평가)

  • Um, Ki Cheon;Yoo, Soon Mi;Yoon, In Ha;Back, Geum Mun
    • The Journal of Korean Society for Radiation Therapy
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    • v.30 no.1_2
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    • pp.83-95
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    • 2018
  • Purpose : After planning the Respiratory Gated Radiotherapy for Lung cancer, the movement and volume change of sparing normal structures nearby target are not often considered during dose evaluation. This study carried out 4-D dose evaluation which reflects the movement of normal structures at certain phase of Respiratory Gated Radiotherapy, by using Deformable Image Registration that is well used for Adaptive Radiotherapy. Moreover, the study discussed the need of analysis and established some recommendations, regarding the normal structures's movement and volume change due to Patient's breathing pattern during evaluation of treatment plans. Materials and methods : The subjects were taken from 10 lung cancer patients who received Respiratory Gated Radiotherapy. Using Eclipse(Ver 13.6 Varian, USA), the structures seen in the top phase of CT image was equally set via Propagation or Segmentation Wizard menu, and the structure's movement and volume were analyzed by Center-to Center method. Also, image from each phase and the dose distribution were deformed into top phase CT image, for 4-dimensional dose evaluation, via VELOCITY Program. Also, Using $QUASAR^{TM}$ Phantom(Modus Medical Devices) and $GAFCHROMIC^{TM}$ EBT3 Film(Ashland, USA), verification carried out 4-D dose distribution for 4-D gamma pass rate. Result : The movement of the Inspiration and expiration phase was the most significant in axial direction of right lung, as $0.989{\pm}0.34cm$, and was the least significant in lateral direction of spinal cord, as -0.001 cm. The volume of right lung showed the greatest rate of change as 33.5 %. The maximal and minimal difference in PTV Conformity Index and Homogeneity Index between 3-dimensional dose evaluation and 4-dimensional dose evaluation, was 0.076, 0.021 and 0.011, 0.0 respectfully. The difference of 0.0045~2.76 % was determined in normal structures, using 4-D dose evaluation. 4-D gamma pass rate of every patients passed reference of 95 % gamma pass rate. Conclusion : PTV Conformity Index was more significant in all patients using 4-D dose evaluation, but no significant difference was observed between two dose evaluations for Homogeneity Index. 4-D dose distribution was shown more homogeneous dose compared to 3D dose distribution, by considering the movement from breathing which helps to fill out the PTV margin area. There was difference of 0.004~2.76 % in 4D evaluation of normal structure, and there was significant difference between two evaluation methods in all normal structures, except spinal cord. This study shows that normal structures could be underestimated by 3-D dose evaluation. Therefore, 4-D dose evaluation with Deformable Image Registration will be considered when the dose change is expected in normal structures due to patient's breathing pattern. 4-D dose evaluation with Deformable Image Registration is considered to be a more realistic dose evaluation method by reflecting the movement of normal structures from patient's breathing pattern.

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