• Title/Summary/Keyword: regional materials

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Analysis on the Aging Process of ac-Plasma Display Panel

  • Park, Min-Soo;Park, Deok-Hai;Kim, Bo-Hyun;Ryu, Byung-Gil;Kim, Sung-Tae;Seo, Gi-Weon;Kim, Dae-Young;Park, Seung-Tea;Kim, Jong-Bin
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.126-129
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    • 2006
  • AC-plasma display panels were examined before and after the aging process to analyze the effect of the aging process. The gas analysis was done to detect the impurity gases out of the MgO film and phosphor by a residual gas analyzer. There were no differences found in the components. The MgO film was analyzed to find out the effect of an ion bombardment due to discharge. The surface roughness of the MgO film was different from regional groups due to the different degree of ion bombardments. XPS analysis showed that the 8 hour aging process was not sufficient to remove $Mg(OH)_2$ and $MgCO_3$ existed on the MgO surface. Photoluminescence measurement showed the small deterioration of blue and green phosphor.

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A Study on the Expression of Materiality in Kuma Kengo's Architecture Space - Focus on the nature material - (쿠마겐코 건축공간에 나타나는 물성표현에 관한 연구 - 자연재료를 중심으로 -)

  • Yoo, Jong-Ho;Lee, Jung-Wook
    • Korean Institute of Interior Design Journal
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    • v.22 no.1
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    • pp.28-37
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    • 2013
  • Architecture of the present time has a general tendency that focuses only in its permanence between the structure and the ground. Architecture has the temporariness. In other words, it is a losing creation. Structure of natural building materials starts its life on the ground and also ends its life on there. Natural building materials leave no building wastes on their ground. Concerns about how to let materials contain not only its physical property but also their regional relation and timely temporariness can let us express materiality of natural building materials in modern construction spaces. And also, it will be the way of recovering the value of architecture and the healing human's sensibility. Kuma Kengo made an attempt that makes the best use of materiality in his work by using them in balance and draw new materiality by a fusion of them. In here, suggestion about the ways of using weak natural materials in modern construction spaces is the main object of this paper. And we can make a progress by analyzing Kuma's expression way of materiality in his work.

Synthesis and Characterization of Rutile TiO2 Powder by the Sulfuric Acid Method (황산법을 이용한 루틸형 TiO2 분말의 제조 및 특성 평가)

  • Choi, Soon Ok;Cho, Jee Hee;Kim, Won Yong;Lim, Sung Hwan
    • Korean Journal of Metals and Materials
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    • v.50 no.7
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    • pp.523-530
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    • 2012
  • We investigated the experimental method that uses the homogeneous precipitation method to prepare mica flakes-coated rutile-type titania pearlescent pigment with urea as a precipitant. $TiO_2$ particles exhibit a high reflection of lights and optical properties with chemical stabilities, so they are appropriate for coating on luminescent pigments (mica). The coating principle of mi ca coated titania with various thicknesses was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and tested by spectrophotometer. Mica with a particle size in the range of $40-60{\mu}m$ was suspended in water, and metal sulphates and urea were added to the mixture, which was heated to boiling. The change in pH was continuously followed. The metal oxide and crystal structure were affected by the conditions of $TiOSO_4$ concentration and reaction time with a sintering temperature the range of $800-1100^{\circ}C$.

The Influence of Ag Thickness on the Electrical and Optical Properties of ZnO/Ag/SnO2 Tri-layer Films

  • Park, Yun-Je;Choi, Jin-Young;Choe, Su-Hyeon;Kim, Yu-Sung;Cha, Byung-Chul;Kim, Daeil
    • Journal of the Korean institute of surface engineering
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    • v.52 no.3
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    • pp.145-149
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    • 2019
  • Transparent and conductive ZnO/Ag/SnO2 (ZAS) tri-layer films were deposited onto glass substrates at room temperature by using radio frequency (RF) and direct current (DC) magnetron sputtering. The thickness values of the ZnO and $SnO_2$ thin films were kept constant at 50 nm and the value for Ag interlayer was varied as 5, 10, 15, and 20 nm. In the XRD pattern the diffraction peaks were identified as the (002) and (103) planes of ZnO, while the (111), (200), (220), and (311) planes could be attributed to the Ag interlayer. The optical transmittance and electrical resistivity were dependent on the thickness of the Ag interlayer. The ZAS films with a 10 nm thick Ag interlayer exhibited a higher figure of merit than the other ZAS films prepared in this study. From the observed results, a ZAS film with a 10 nm thick Ag interlayer was believed to be an alternative transparent electrode candidate for various opto-electrical devices.

Synthesis of the Multi-layered SnO Nanoparticles and Enhanced Performance of Lithium-Ion Batteries by Heat treatment (다층 산화주석(SnO)의 합성 및 열처리를 통한 리튬이온 이차전지 음극 소재의 성능 향상)

  • Lee, So Yi;Myung, Yoon;Lee, Kyu-Tae;Choi, Jaewon
    • Journal of Powder Materials
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    • v.28 no.6
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    • pp.455-461
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    • 2021
  • In this study, multilayered SnO nanoparticles are prepared using oleylamine as a surfactant at 165℃. The physical and chemical properties of the multilayered SnO nanoparticles are determined by transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Interestingly, when the multilayered SnO nanoparticles are heated at 400℃ under argon for 2 h, they become more efficient anode materials, maintaining their morphology. Heat treatment of the multilayered SnO nanoparticles results in enhanced discharge capacities of up to 584 mAh/g in 70 cycles and cycle stability. These materials exhibit better coulombic efficiencies. Therefore, we believe that the heat treatment of multilayered SnO nanoparticles is a suitable approach to enable their application as anode materials for lithium-ion batteries.

p53 Codon 72 Polymorphism Interactions with Dietary and Tobacco Related Habits and Risk of Stomach Cancer in Mizoram, India

  • Malakar, Mridul;Devi, K. Rekha;Phukan, Rup Kumar;Kaur, Tanvir;Deka, Manab;Puia, Lalhriat;Sailo, Lalrinliana;Lalhmangaihi, T.;Barua, Debajit;Rajguru, Sanjib Kumar;Mahanta, Jagadish;Narain, Kanwar
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.2
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    • pp.717-723
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    • 2014
  • Background: This study was carried out to investigate the interaction of p53 codon 72 polymorphism, dietary and tobacco habits with reference to risk of stomach cancer in Mizoram, India. A total of 105 histologically confirmed stomach cancer cases and 210 age, sex and ethnicity matched healthy population controls were included in this study. Materials and Methods: The p53 codon 72 polymorphism was detected by PCR-RFLP and sequencing. H. pylori infection status was determined by ELISA. Information on various dietary and tobacco related habits was recorded with a standard questionnaire. Results: This study revealed that overall, the Pro/Pro genotype was significantly associated with a higher risk of stomach cancer (OR, 2.54; 95%CI, 1.01-6.40) as compared to the Arg/Arg genotype. In gender stratified analysis, the Pro/Pro genotype showed higher risk (OR, 7.50; 95%CI, 1.20-47.0) than the Arg/Arg genotype among females. Similarly, the Pro/Pro genotype demonstrated higher risk of stomach cancer (OR, 6.30; 95%CI, 1.41-28.2) among older people (>60 years). However, no such associations were observed in males and in individuals <60 years of age. Smoke dried fish and preserved meat (smoke dried/sun dried) consumers were at increased risk of stomach cancer (OR, 4.85; 95%CI, 1.91-12.3 and OR, 4.22; 95%CI, 1.46-12.2 respectively) as compared to non-consumers. Significant gene-environment interactions exist in terms of p53 codon 72 polymorphism and stomach cancer in Mizoram. Tobacco smokers with Pro/Pro and Arg/Pro genotypes were at higher risk of stomach cancer (OR, 16.2; 95%CI, 1.72-153.4 and OR, 9.45; 95%CI, 1.09-81.7 respectively) than the non-smokers Arg/Arg genotype carriers. The combination of tuibur user and Arg/Pro genotype also demonstrated an elevated risk association (OR, 4.76; 95%CI, 1.40-16.21). Conclusions: In conclusion, this study revealed that p53 codon 72 polymorphism and dietary and tobacco habit interactions influence stomach cancer development in Mizoram, India.

Local and regional recurrence following mastectomy in breast cancer patients with 1-3 positive nodes: implications for postmastectomy radiotherapy volume

  • Park, Shin-Hyung;Lee, Jeeyeon;Lee, Jeong Eun;Kang, Min Kyu;Kim, Mi Young;Park, Ho Yong;Jung, Jin Hyang;Chae, Yee Soo;Lee, Soo Jung;Kim, Jae-Chul
    • Radiation Oncology Journal
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    • v.36 no.4
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    • pp.285-294
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    • 2018
  • Purpose: To determine the necessity of postmastectomy radiotherapy (PMRT) and which regions would be at risk for recurrence, we evaluated local and regional recurrence in breast cancer patients with 1-3 positive nodes and a tumor size of <5 cm. Materials and Methods: We retrospectively analyzed data of 133 female breast cancer patients with 1-3 positive nodes, and a tumor size of <5 cm who were treated with mastectomy followed by adjuvant systemic therapy between 2007 and 2016. The median follow-up period was 57 months (range, 12 to 115 months). Most patients (82.7%) were treated with axillary lymph node dissection. Adjuvant chemotherapy, endocrine therapy, and trastuzumab therapy were administered to 124 patients (93.2%), 112 (84.2%), and 33 (24.8%), respectively. The most common chemotherapy regimen was anthracycline and cyclophosphamide followed by taxane (71.4%). Results: Three patients (2.3%), 8 (6.0%), and 12 (9.0%) experienced local, regional, and distant failures, respectively. The 5-year cumulative risk of local recurrence, regional recurrence, distant metastasis, and disease-free survival was 3.1%, 8.0%, 11.7%, and 83.4%, respectively. There were no statistically significant clinicopathologic factors associated with local recurrence. Lymphovascular invasion (univariate p = 0.015 and multivariate p = 0.054) was associated with an increased risk of regional recurrence. Conclusion: Our study showed a very low local recurrence in patients with 1-3 positive nodes and tumor size of <5 cm who were treated with mastectomy and modern adjuvant systemic treatment. The PMRT volume need to be tailored for each patient's given risk for local and regional recurrence, and possible radiation-related toxicities.

A Study on the Measurement of Knowledge Relatedness Density and Technological Complexity in South-east Region (동남권 지역의 지식 간 연관성 밀도와 기술 복합성 측정에 관한 연구)

  • Park, Gi-Woong;Kim, Donghyun
    • Journal of the Korean Regional Science Association
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    • v.37 no.3
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    • pp.3-18
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    • 2021
  • The fourth Industrial Revolution is transforming the industrial structure of the region, and it is necessary to develop new industries and technologies that reflect regional characteristics. The purpose of this study is to measure the knowledge relatedness and technological complexity in Busan, Ulsan, and Gyeongnam, and to identify technologies with potential for regional industrial differentiation strategies. Using patent data from 2015 to 2019, co-occurrence matrices were derived from 652 IPC codes, and the knowledge relatedness density and technology complexity index were calculated. Network analysis was performed using the knowledge relatedness density. As a result of analysis, it was found that mechanical engineering occupied a large proportion, followed by chemistry and electrical engineering. As a result of applying the risk-benefit framework to derive technologies with the potential to differentiate local industries, the technological capabilities of low-risk-high-benefit were different. Among mechanical engineering, technologies such as engine, machine operation, and transportation were included in Busan. In Ulsan, environmental technology in chemical and materials, and heat treatment technology in mechanical engineering were technologies with low-risk and high-benefit capabilities. Gyeongnam showed competence in mechanical engineering, chemistry, and electrical engineering in some areas such as Gimhae, Yangsan, and Changwon. The results of this study are meaningful in that they identified technologies with potential for selecting and deriving strategic industries for regional growth based on latent knowledge in the region.

An Exploratory Research on Measuring the Local and Regional Impacts of Universities (대학이 지역에 미치는 영향 지표 개발을 위한 탐색적 연구)

  • Shin, Jin-Young;Lee, Jong-Ho
    • Journal of the Korean association of regional geographers
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    • v.23 no.3
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    • pp.437-449
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    • 2017
  • As a new duty of universities, contributions to localities and regions are magnified as an important issue and overseas universities are creating it as the index to use self evaluations and public relations actively. The universities in Korea are expanding resources usage of university and proceeding various businesses to enhance co-operation with local government, civic groups and companies lately. However, it is still in an embryo. This study is aiming to analyze cases of foreign universities and the socio-economic impacts of university on the region and discover evaluation index based on the results to be applied to the universities in Korea. This study had considered the evaluation of local effect by the university conducted by the Higher Education Funding Council for England(HEFCE) which is the representative case to analyze the impacts of university on the region at the level of government and independent organizations. The applicable common index had been extracted for universities in Korea from case studies on University of Rochester in the US and University of Birmingham in the UK considered as a representative university in North America and Europe respectively which are publishing a white paper on local and regional impacts of the university by using various index. As a result, 24 items in six areas(economic influence, research, education, art & cultural services, regional development, and the field of university specialization) had been deducted as the evaluation index which represents the local and regional impacts of university. This index could be secured through holding materials of each university and 'Higher Education in KOREA' as university information disclosure service and it might be applied to the universities in Korea.

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Regional Differences in Blood-Brain Barrier Permeability in Cognitively Normal Elderly Subjects: A Dynamic Contrast-Enhanced MRI-Based Study

  • Il Heon Ha;Changmok Lim;Yeahoon Kim;Yeonsil Moon;Seol-Heui Han;Won-Jin Moon
    • Korean Journal of Radiology
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    • v.22 no.7
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    • pp.1152-1162
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    • 2021
  • Objective: This study aimed to determine whether there are regional differences in the blood-brain barrier (BBB) permeability of cognitively normal elderly participants and to identify factors influencing BBB permeability with a clinically feasible, 10-minute dynamic contrast-enhanced (DCE) MRI protocol. Materials and Methods: This IRB-approved prospective study recruited 35 cognitively normal adults (26 women; mean age, 64.5 ± 5.6 years) who underwent DCE T1-weighted imaging. Permeability maps (Ktrans) were coregistered with masks to calculate the mean regional values. The paired t test and Friedman test were used to compare Ktrans between different regions. The relationships between Ktrans and the factors of age, sex, education, cognition score, vascular risk burden, vascular factors on imaging, and medial temporal lobar atrophy were assessed using Pearson correlation and the Spearman rank test. Results: The mean permeability rates of the right and left hippocampi, as assessed with automatic segmentation, were 0.529 ± 0.472 and 0.585 ± 0.515 (Ktrans, x 10-3 min-1), respectively. Concerning the deep gray matter, the Ktrans of the thalamus was significantly greater than those of the putamen and hippocampus (p = 0.007, p = 0.041). Regarding the white matter, the Ktrans value of the occipital white matter was significantly greater than those of the frontal, cingulate, and temporal white matter (p < 0.0001, p = 0.0007, p = 0.0002). The variations in Ktrans across brain regions were not related to age, cognitive score, vascular risk burden, vascular risk factors on imaging, or medial temporal lobar atrophy in the study group. Conclusion: Our study demonstrated regional differences in BBB permeability (Ktrans) in cognitively normal elderly adults using a clinically acceptable 10-minutes DCE imaging protocol. The regional differences suggest that the integrity of the BBB varies across the brains of cognitively normal elderly adults. We recommend considering regional differences in Ktrans values when evaluating BBB permeability in patients with neurodegenerative diseases.