• Title/Summary/Keyword: density index

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Morphologies of Aragonite Synthesized from Scallop Shells and Lime Stones by Successive Reaction

  • Keiko Sasaki;Hiroyuki Kobayashi;Yoo, Kyoung-Keun;Masami Tsunekawa
    • Proceedings of the IEEK Conference
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    • 2001.10a
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    • pp.331-336
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    • 2001
  • Aragonite type of precipitated calcium carbonate was synthesized by the successive reaction with hybridization of waste scallop shells with limestone. In the first step, carbonation was performed by using calcined limestone with low brightness, followed by the additional carbonation using calcined-hydrous scallop shells with high brightness. The temperature and the amount ratio of calcined limestone to calcined-hydrous scallop shells were examined as parameters in the experimental conditions. The products were characterized by XRD, SEM. in addition to measurements of brightness index. the specific surface area, and bulk density. The amount ratio of limestone to scallop shell affected not only the brightness but also morphologies of products. The increase in relative amounts of limestone leads to decrease in brightness and bumpy surface of particles. High temperature reaction produces aragonite particles with longer sizes and higher bulk densities. This study has made an attempt to establish the synthesis of aragonite with high brightness and high strength by utilization of waste scallop shells.

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A Study on Occupational History of Coal Workers' Pneumoeoniosis (석탄광부폐증자의 직업력에 관한 연구)

  • Chung, Ho-Keun;Cheon, Yong-Hee;Rhee, Kyung-Young;Hong, Jeong-Pyo
    • Journal of Preventive Medicine and Public Health
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    • v.20 no.1 s.21
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    • pp.158-164
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    • 1987
  • The purpose of this study is to analyze occupational history of coal miners with pneumoconiosis. In this study, occupational characteristics of 49 coal miners with pneumoconiosis were compared with those of 45 coal miners without pneumoconiosis but in similar age category($43{\sim}52$ years of age) based on interview survey. Various indices on occupational characteristics were developed for the following areas: duration of employment, perception of working condition, working density, dust concentration, temperature, humidity, and experience of respirator wearings. Perception of working condition were measured in 5 points scales but experiences of respirator wearing was measured in 3 points scale. Each index was multiplied by duration of employment. From the analysis, only the experience of respirator wearing showed statistically significant difference between the two groups. Therefore, respirator wearing seemed to be effective in reducing occurrence of pneumoconiosis.

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AKARI near-infrared spectral observations on the shocked H2 gas of a supernova remnant IC 443

  • Shinn, Jong-Ho;Koo, Bon-Chul;Seon, Kwang-Il;Lee, Ho-Gyu
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.1
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    • pp.69.1-69.1
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    • 2010
  • IC 443 is famous for its interaction with nearby molecular clouds and intense H2 emission lines in infrared. Therefore, it has been studied extensively for the understanding of molecular shocks. We observed H2 mission lines toward the shock-cloud interaction regions of IC 443, known as clumps B, C, and G. The observations were performed with the InfraRed Camera (IRC) onboard a satellite AKARI over 2.5-5.0 um, where previous space observations, e.g. Infrared Space Observatory (ISO) and Spitzer, do not cover. Our AKARI observations provide spectra of sequential pure-rotational and ro-vibrational H2 emission lines. For the clumps C and G, combining with previous mid-infrared observational results, we found that the H2 level populations show a significant separation between v=0 and v=1 levels; v=1 levels are under-populated than v=0 levels, therefore, the population cannot be described by two temperature LTE model, as many people have analyzed for the shocked H2 gas. We also applied the thermal admixture model, dN(H2; T)~T^(-b) dT, with varying ortho-to-para ratios according to the temperature, to describe the level population, and obtained plausible ranges of the H2 gas density and power-law index b.

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Increase in Systolic Blood Pressure and Creatinine among Type 2 Diabetic Patients with Microalbuminuria (미세 단백뇨가 있는 제 2형 당뇨병 환자에서의 수축기 혈압과 Creatinine 증가)

  • Song Min Sun;Kim Hee Seung;Yoo Yang Sook
    • Journal of Korean Public Health Nursing
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    • v.16 no.2
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    • pp.346-353
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    • 2002
  • The purpose of this study was to identify clinical characteristics of type 2 diabetic patients with microalbuminuria. The subjects were 390 out type 2 diabetic patients from beginning of March through the end of April in 2001, who visited at the endocrine center at Kangnam St. Mary's Hospital of Catholic University in Seoul. The patients' clinical laboratory data were assessed at medical record review. The data were analyzed using for t-test and $\chi^2$ test. The results were as follows : 1. There were no significant differences in age, body mass index, family history of diabetes and hypoglycemic agents between normoalbuminuria group and microalbuminuria group. 2. The level of systolic blood pressure and creatinine of microalbuminuria group were higher than those of normoalbuminuria group. There were no significant differences in HbAlc, fasting blood glucose, 2-hour postprandial blood glucose, diastolic blood pressure, total cholesterol, triglyceride, high density lipoprotein cholesterol, lipoprotein(a) and blood urea nitrogen between normoalbuminuria group and microalbuminuria group.

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Ecological Studies on the Coastal Plants in Korea-Floristic Compositon and Standing Crop of the Sand Duen on the Southern Coast (한국 해안식물의 생태학적 연구 - 남해안의 사구식물군락의 종조성과 현존량)

  • Lee, Woo Tchul;Sand-Keun Chon
    • The Korean Journal of Ecology
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    • v.6 no.3
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    • pp.177-186
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    • 1983
  • Vegetation types and their standing crop in the sand dune on the south coast of Korea was investigated by the method of Curtis, J.T. and McIntosh, R.P. (1951). The relationship between vegetation types and environmental factors was also analyzed. The dominant species in the vegetations of the south coast sand dune were Carex pumila, Calystegia soldamella, Imperata cylindrica var. koenigii, Vitex rotundifolia, Ixeris repens, Carex kobomugi, Zoysia macrostachya. The species density in the sand dune vegetation increased with the distance from the coast, psammophyte and rhizome psammophyte decreased with the distance from the coast but other plants increased. The standing crop of the sand dune vegetatiion was average $53.79g/m^2$. An individual standing crop of Vitex routundifolia and Carex kobomugi varied with the curve of secondary degree. The salt content of the sand dune soil from 2.95 to 11.78 mg %, and it was not significant differences among stands, but it was varied with the distance form the coast. Negative relationship between warmth index and aboveground standing crop was found and the formula y=283.8886 - 2.4910X could be estimated.

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Effects of the UV beam parameters on the fiber Bragg gratings fabricated (UV beam parameter가 광섬유 격자 형성에 미치는 영향)

  • Lim, J.H.;Cho, S.Y.;Kim, S.Y.;Park, K.N.;Lee, J.H.;Park, P.O.;Song, J.T.;Lee, K.S.;Jeon, C.O.
    • Proceedings of the KIEE Conference
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    • 1997.11a
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    • pp.665-668
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    • 1997
  • We fabricated a number of optical fiber Bragg gratings by varying the UV beam parameters such as the laser energy density, pulse repetition rate and exposing time. The reflectance and the Bragg wavelength shift of the fiber Bragg gratings formed with a KrF excimer laser in real time depend strongly on the UV beam parameters. The index changes in the gratings during the exposing time are well fitted to the well known equations.

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Condition assessment of raking damaged bulk carriers under vertical bending moments

  • Kim, Do Kyun;Yub, Su Young;Choi, Han Suk
    • Structural Engineering and Mechanics
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    • v.46 no.5
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    • pp.629-644
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    • 2013
  • This paper concerns about the raking damages on the ultimate residual hull girder strength of bulk carriers by applying the modified R-D diagram (advanced method). The limited raking damage scenarios, based on the IMO's probability density function of grounding accidents, were carried out by using sampling technique. Recently, innovative method for the evaluation of the structural condition assessment, which covers the residual strength and damage index diagram (R-D diagram), was proposed by Paik et al. (2012). This concept is applied in the present study and modified R-D diagram, which can be considered vessel size effect, is then proposed. Four different types of bulk carrier structures, i.e., Handysize (37K), Supramax (57K), Kamsarmax (82K) and Capesize (181K) by Common Structural Rule (CSR), were applied to draw the general tendency. The ALPS/HULL, intelligent supersize finite element method, was employed for the ultimate longitudinal strength analysis. The obtained empirical formulas will be useful for the condition assessment of bulk carrier structures. It can also cover different sizes of the bulk carriers in terms of ultimate longitudinal strength. Important insights and findings with useful guidelines developed in this study are summarized.

Lack of Efficacy of Tai Chi in Improving Quality of Life in Breast Cancer Survivors: a Systematic Review and Meta-analysis

  • Yan, Jun-Hong;Pan, Lei;Zhang, Xiao-Min;Sun, Cui-Xiang;Cui, Guang-He
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.8
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    • pp.3715-3720
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    • 2014
  • Background: It is controversial whether Tai Chi (TC) benefits breast cancer survivors (BCS) on quality of life (QoL). We therefore undertook a meta-analysis to assess this question. Materials and Methods: A computerized search through electronic databases was performed to identify relevant randomized controlled trials (RCTs). The primary outcome was QoL, while secondary outcomes included body mass index (BMI), bone mineral density (BMD), and muscle strength. Results: Five RCTs involving 407 patients were included in the meta-analysis. The pooled standardized mean differences were 0.10 (95% confidence interval (CI): -0.35-0.54) for physical well-being, 0.03 (95%CI: -0.18-0.25) for social/family well-being, 0.24 (95%CI: 0.02-0.45) for emotional well-being, 0.23 (95%CI: -0.03-0.49) for functional well-being, and 0.09 (95%CI: -0.19-0.36) for additional concerns. TC failed to improve BMI, BMD, and muscle strength. Conclusions: There is currently lack of sufficient evidence to support TC improving QoL and other important clinical endpoints.

TARGETING RECEPTOR TYROSINE KINASE ON ENDOTHELIAL CELLS IN AN ORTHOTOPIC TUMOR MODEL OF ORAL SQUAMOUS CELL CARCINORMA (구강 편평상피세포암 동위종양 모델에서 내피세포의 수용체 타이로신 인산화효소에 대한 표적치료)

  • Park, Young-Wook;Kim, So-Hee
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.35 no.2
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    • pp.55-65
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    • 2009
  • Purpose: We determined the therapeutic effects of blockade of epidermal growth factor(EGF) and vascular endothelial growth factor(VEGF) receptor tyrosine kinases on the growth of oral squamous cell carcinoma(OSCC) xenografted in athymic nude mice. Experimental Design: We investigated the in vivo antitumor effects of a tyrosine kinase inhibitor for EGFR and VEGFR-2, AEE788 in a mouth floor(orthotopic) tumor model. Nude mice with orthotopic tumors were randomized to receive AEE788, paclitaxel, a combination of AEE788 and paclitaxel, or control. Antitumor mechanisms of AEE788 were determined by immunohistochemical/immunofluorescent and apoptosis assays. Results: Tumors of mice treated with AEE788 demonstrated down-regulation of phosphorylated EGFR, phosphorylated VEGFR and their downstream mediators(pMAPK and pAkt), decreased proliferative index, decreased microvessel density(MVD). As a result, growth of the primary tumor and nodal metastatic potentials were inhibited by AEE788. Conclusion: These data show that EGFR and VEGFR can be molecular targets for the treatment of OSCC.

Electra-Optic and Ionic Properties of Twisted Nematic Cells With Different Chiral Pitch

  • Kim, Sung-Woon;Park, Hee-Do;Kim, Hee-Cheol;Park, Young-Il;Suh, Dong-Hae;Lee, Won-Geon;Park, Hae-Sung
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.504-507
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    • 2002
  • We investigated electro-optic and ionic properties of twisted nematic cells by using control of chiral pitch. These properties are observed in practical experiment and simulations. C-V and V-T curve characteristics were obtained from three types of cells with d/p. It is shown that d/p ratio of short cells exhibit faster response time improved by 20% than normal cell. Also, inter-gray response time is improved each rise time and decay time. And, the increase of saturation voltage is happened because of the small twist angel change from initial state at high voltage near 5V. To compensate for longer black level tail, gamma curve index was varied from g = 2.2 to g = 2.7 in module status. Additionally, adding chiral dopant into TN cells improved ionic characteristics such as increasing VHR, Ion density and DC Hysteresis were decreased..

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