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Regional Background Levels of Carbon Monoxide Observed in East Asia during 1991~2004 (1991~2004년 동아시아에서 관측한 일산화탄소의 지역적 배경 농도)

  • Kim, Hak-Sung;Chung, Yong-Seung
    • Journal of the Korean earth science society
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    • v.27 no.6
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    • pp.643-652
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    • 2006
  • Data of the carbon monoxide concentration observed in Mt. Waliguan in China (WLG), Ulaan Uul in Mongolia (UUM), Tae-ahn Peninsula in Korea (TAP), and Ryori in Japan (RYO) were analyzed for a long period between 1991 and 2004. The annual average concentration of carbon monoxide was the highest at TAP $(233{\pm}41ppb)$ followed by $RYO(171{\pm}36ppb),\;UUM(155{\pm}26ppb),\;and\;WLG(135{\pm}22ppb)$. The seasonal variations being high in spring and low in summer were observed in other areas of Eastern Asia except WLG. TAP was high in carbon monoxide concentration in all seasons compared to WLG, UUM and RYO and shows wide distribution of concentration in the histogram, which is caused by the influence of large-scale air pollution due to its downwind location close to the East Asian continent, China in particular. Also, our data was compared with data measured at Mauna Loa (MLO) in Hawaii. According to the origin of the isentropic backward trajectory and its transport passage, carbon monoxide concentration observed in TAP was analyzed as follows: continental background airflows (CBG) were $216{\pm}47ppb$; regionally polluted continental airflows (RPC) were $316{\pm}56ppb$; Oceanic background airflows (OBG) were $108{\pm}41ppb$; and Partly perturbed oceanic airflows (PPO) were $161{\pm}6ppb$. The high concentration of carbon monoxide in TAP is due to the airflow from East Asian continent origin rather than that from the North Pacific origin. Especially, RPC which passes through the eastern China appeared to be the highest in concentration in spring, fall, and winter. However, OBG was affected by the North Pacific air mass with a low carbon monoxide concentration in summer. The NOAA satellite images and GEOS-CHEM model simulation confirmed a large-scale air pollution event that was in the course of expansion from southeastern China bound to the Korean Peninsula and the Korea East Sea by way of the Yellow Sea.

To Compare and Analyze Costumes in the Film "The Great Gatsby" and Y&Kei Collection (영화 "The Great Gatsby" 의상과 Y&Kei 컬렉션 비교 분석)

  • O, Ji-Hye;Lee, In-Seong
    • The Research Journal of the Costume Culture
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    • v.16 no.6
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    • pp.1050-1063
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    • 2008
  • A movie is a fiction made on a basis of an author's and a writer's imagination, but all sorts of properties mixed with each other and most realistically expresses the era which becomes the background of a movie and acts as a carrier that connects designers with consumers. Thus, this study was carried out to review how the fashion products that designer's intention and commercial value added are expressed in collections by comparing and analysing the costumes in the movie "The Great Gatsby" that described the life of America's upper-class in 1920s and the 04 S/S Y&Kei collection which were proceeding after getting inspiration from this movie. For this, literature materials were inspected in order to make a theoretical review on social and cultural background and costumes history background in 1920s and the photo materials on movie costume were collected and analysed using DVD video captures, as well as the photo materials on 04 S/S Y&Kei were collected and analyzed through the institute providing domestic fashion information. The following conclusion was deduced through this study. First, in 1920s which becomes the background of this study, the slim shape of Flapper which looks like a young and boy became an ideal figure condition and the straight silhouette with low waist line and the short skirt that rose to knee was popular. Second, as a result of analysing movie costume by classifying it in silhouette, colors, and materials, straight silhouette of low waistline with a near colored - tone seen in the pastel series, including white, beige, pink, and gray was mainly constituted and the metal colors like silver and gold were used. As a material, chiffon, satin, velvet, flower patterned prints, and beads were used, which represented luxurious life of women in the upper classes. Third, as a result of comparing and analysing, it turned out that there was a similarity. However, in dress collection for a heroine, some dissimilarity differentiated from a movie costumes was found out in that the dresses in collection expressed moderate beauty and modernism and elegant beauty at the same time by matching a variety of materials and using black color.

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Socioeconomic Disparities in Pregnancy Outcome and Infant Mortality: Extremely Low Birth Weight and Very Low Birth Weight Infants in Korea, 1995-2010 (극소 및 초극소 저체중출생아 출생과 사망의 사회적 불평등)

  • Park, Hye-Jeong;Son, Mia
    • Health Policy and Management
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    • v.25 no.4
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    • pp.277-284
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    • 2015
  • Background: This study investigates the relationship of socioeconomic status with adverse birth outcomes (low birth weight, preterm birth) and the relationship of socioeconomic status with infant mortality, using the birth cohort in Korea, 1995-2010. Methods: 8,648,035 births from National Statistics Offics, 1995-2010 were studied with respect to social variation in adverse birth outcomes and infant mortality in Korea. The effect of social inequality was examined against adverse birth outcomes and infant mortality using multivariate logistic regression after controlling for other covariates. Results: Social inequality were observed in adverse birth outcomes: low birth weight (LBW, 1,500-2,499 g), very LBW (1,000-1,499 g), and extremely LBW (500-999 g) as well as moderately preterm birth (PTB, 33-36 weeks), very PTB (28-32 weeks), extremely PTB (22-27 weeks), and infant mortality. The effect of social inequality was higher among moderately LBW (1,500-2,499 g) and PTB (33-36 weeks) than very or extremely LBW and PTB. Conclusion: The social inequality in adverse birth outcomes (low birth weight and preterm) and infant mortality existed and increased in Korea from 1995 to 2010. The effect of maternal education on adverse birth outcomes as well as infant mortality was apparent in the study results. Especially, social inequailiy in infant mortality was greater among the sub-normal births (low birth weight [1,500-2,499 g] or preterm birth [33-36 weeks]), which suggests, social interventions should aim at more among the subnormal births. This study suggest that tackling inequality in births as well as infant mortality should be focused on the social inequality itself.

Calculation of Low-Energy Reactor Neutrino Spectra for Reactor Neutrino Experiments

  • Riyana, Eka Sapta;Suda, Shoya;Ishibashi, Kenji;Matsuura, Hideaki;Katakura, Jun-ichi
    • Journal of Radiation Protection and Research
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    • v.41 no.2
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    • pp.155-159
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    • 2016
  • Background: Nuclear reactors produce a great number of antielectron neutrinos mainly from beta-decay chains of fission products. Such neutrinos have energies mostly in MeV range. We are interested in neutrinos in a region of keV, since they may take part in special weak interactions. We calculate reactor antineutrino spectra especially in the low energy region. In this work we present neutrino spectrum from a typical pressurized water reactor (PWR) reactor core. Materials and Methods: To calculate neutrino spectra, we need information about all generated nuclides that emit neutrinos. They are mainly fission fragments, reaction products and trans-uranium nuclides that undergo negative beta decay. Information in relation to trans-uranium nuclide compositions and its evolution in time (burn-up process) were provided by a reactor code MVP-BURN. We used typical PWR parameter input for MVP-BURN code and assumed the reactor to be operated continuously for 1 year (12 months) in a steady thermal power (3.4 GWth). The PWR has three fuel compositions of 2.0, 3.5 and 4.1 wt% $^{235}U$ contents. For preliminary calculation we adopted a standard burn-up chain model provided by MVP-BURN. The chain model treated 21 heavy nuclides and 50 fission products. The MVB-BURN code utilized JENDL 3.3 as nuclear data library. Results and Discussion: We confirm that the antielectron neutrino flux in the low energy region increases with burn-up of nuclear fuel. The antielectron-neutrino spectrum in low energy region is influenced by beta emitter nuclides with low Q value in beta decay (e.g. $^{241}Pu$) which is influenced by burp-up level: Low energy antielectron-neutrino spectra or emission rates increase when beta emitters with low Q value in beta decay accumulate Conclusion: Our result shows the flux of low energy reactor neutrinos increases with burn-up of nuclear fuel.

Objective and Subjective Socioeconomic Position and Current Smoking Among Korean Adolescents

  • Ko, Min Jung;Lee, Eun Young;Kim, Kirang
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.20
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    • pp.8877-8881
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    • 2014
  • Background: Despite social gradients in adult smoking, the effects of socioeconomic position (SEP) on adolescent smoking is not well understood. This study examined effects of subjective SEP as well as the objective SEP on smoking among Korean adolescents. Materials and Methods: Data were obtained from the 2012 Korea Youth Risk Behavior Web-based Survey, a nationally representative sample of middle and high school students (38,221 boys; 35,965 girls). SEP was assessed by the Family Affluence Scale (FAS) and the self-rated household economic status. Relationships between SEP and smoking were analyzed by multivariate logistic regression. Results: The low perceived SEP for either the high or low FAS grade was related to an elevated likelihood of smoking in both genders. A significantly higher risk of smoking was found in boys of low perceived SEP in middle school (odds ratio [OR] 1.50; 95% confidence interval [CI] 1.28-1.77 for high FAS, OR 1.55; 95% CI 1.21-1.98 for low FAS), and of low perceived SEP and high FAS in high school (OR 1.13; 95% CI 1.02-1.26). Among girls, an elevated risk of smoking was observed in middle school group with low perceived SEP and low FAS (OR 2.01; 95% CI 1.44-2.79) and in the high school group of low perceived SEP, regardless of FAS level (OR 1.34; 95% CI 1.14-1.57 for high FAS, OR 1.31; 95% CI 1.04-1.65 for low FAS). Conclusions: The relationship of subjectively perceived SEP with smoking is as important as objective SEP and more significant in Korean high school adolescents.

Comparison Study of Static and Dynamic Plantar Foot Pressure between Chronic Low Back Pain Patients and Normal Adults (만성 요통 환자와 정상 성인의 정적, 동적 족저압 비교 연구)

  • Lee, Jeon-Hyeong;Kim, Gi-Chul;Seo, Hyun-Kyu;Park, Youn-Ki
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.19 no.1
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    • pp.49-54
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    • 2013
  • Background: The purposed of this study is to examine the static and dynamic plantar foot pressure in chronic low back pain patients and normal adults. Methods: The subjects were divided into a group of 30 patients with chronic low back pain and a control group of 30 healthy persons. While static posture and dynamic posture at comfortable walking speeds, the low back pain group and the control group measured their plantar foot pressure and the trajectory of their center of pressure (COP) using the Matscan(R) system. Independent t-tests were measured to compare differences in plantar foot pressure characteristics between the left side and right side of the low back pain group and the control group. Results: In the comparison of differences in plantar foot pressure characteristics between the left side and right side of the low back pain group and the control group, the anteroposterior (AP) displacement of COP showed significant differences (p<.05). Although the low back pain group and the control group did not show any significant differences in leg length, weight distribution, mediolateral (ML) displacement of COP, static contract area, dynamic contract areas (p>.05), increases in the contract area values were shown in the hind foot in general. Conclusion: In this study, it was shown that patients with chronic low back pain were walking with short AP displacement of the COP as a compensatory action to avoid pain.

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Time Evolution of a High-temperature GaN Epilayer Grown on a Low-temperature GaN Buffer Layer using a Low-pressure MOCVD

  • Chang, Kyung-Hwa;Cho, Sung-Il;Kwon, Myoung-Seok
    • Transactions on Electrical and Electronic Materials
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    • v.7 no.1
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    • pp.36-41
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    • 2006
  • In this paper, the time evolution of undoped GaN epilayers on a low-temperature GaN buffer layer grown on c-plane sapphire at a low pressure of 300 Torr was studied via a two-step growth condition in a horizontal MOCVD reactor. As a function of the growth time at a high-temperature, the surface morphology, structural quality, and optical and electrical properties were investigated using atomic force microscopy, high-resolution x-ray diffraction, photoluminescence, and Hall effect measurement, respectively. The root-mean-square roughness showed a drastic decrease after a certain period of surface roughening probably due to the initial island growth. The surface morphology also showed the island coalescence and the subsequent suppression of three-dimensional island nucleation. The structural quality of the GaN epilayer was improved with increasing growth time considering the symmetrical (002) and asymmetrical (102) rocking curves. The variations of room-temperature photoluminescence, background carrier concentration, and Hall mobility were measured and discussed.

Development of Phased Array Ultrasonic Testing Technique for Nuclear Power Plant Cast Piping Weld (원자력발전소 주조 배관 용접부 위상배열 초음파검사 기술 개발)

  • Yoon, Byungsik;Yang, Seunghan;Kim, Yongsik
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.6 no.1
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    • pp.16-22
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    • 2010
  • Cast austenitic stainless steel(CASS) is used in the primary cooling piping system of nuclear power plant for it's relative low cost, corrosion resistance and easy of welding. However, the coarse-grain structure of cast austenitic stainless steel can strongly affect the inspectability of ultrasonic testing. The major problems encountered during inspection are beam skewing, high attenuation and high background noise of CASS component. So far, the best inspection performance involving CASS components have been achieved using low frequency TRL(Transmitter/Receiver side-by-side L wave) angle beam probe. But TRL technique could not detect shallow defect and it contains an uncertainty for sizing capability. Currently, most of researchers are studying to overcome these challenge issue. In this study, low-frequency phased array TRL technique used to detect and sizing the flaws in CF8A cast austenitic stainless steel.As conclusion, we could detect and size not only axial flaw but also circumferential flaw using low frequency phased array technique.

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May Low Level Laser Therapy be the Candidate of First Choice for the Acute Stroke? (중풍 급성기에 있어서 레이저치료에 대한 최신지견 고찰 : 임상 논문을 중심으로)

  • Yang, Chang-Sop;Jang, In-Soo;Sun, Seung-Ho
    • The Journal of Internal Korean Medicine
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    • v.31 no.3
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    • pp.612-619
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    • 2010
  • Background : Low level laser therapy may be an effective method to protect tissue damage in acute stroke. Recently, series of clinical studies on the basis of animal experiments report efficacy and safety of laser therapy at early stages of acute stroke. Laser promotes mitochondrial ATP synthesis to reduce cell death by ischemic infarction. Objectives : To report possibility of non-invasive laser therapy for acute stroke by reviewing literature about its effectiveness, safety and mechanism. Methods : We searched papers using PubMed and 'Web of Knowledge' of Thomson ISI, using the keywords "Laser Therapy, Low-Level" and "Stroke". Limitations were last 10 years of publications and only in English. Search range includes RCTs, clinical reports, reviews and animal experiments. Papers not matched with inclusion criteria were excluded. Results : A total 223 studies were found, 203 excluded during title and extract screening. After scanning 20 papers the final 2 serial RCTs were selected and analyzed. They reported that transcranial laser therapy led in neuroprotective effect for acute stroke patents. Clinical evaluation factors showed favorable trend and initial safety. Conclusions : Non-invasive laser secured safety of clinical application. It may be a favorable choice for the acute stage of stroke.

The Influence of Hearing Ability of Ordinary People on the Quality of Life (일반인의 청력이 삶의 질에 미치는 영향)

  • Kim, Seok-Hwan;Oh, Ji-Young
    • Health Policy and Management
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    • v.28 no.2
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    • pp.162-167
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    • 2018
  • Background: In this research, we conducted an analysis to grasp the relationship between hearing and quality of life and to prepare effective troubleshooting. Methods: In this study, we analyzed using the data of the 6th term of the National Health and Nutrition Survey of the Disease Management Headquarters. And, out of 7,380 people, 3,598 adults over the age of 40 years who participated in the hearing test were selected as final research subjects and analyzed. Results: It was confirmed that the result of the analysis affects the quality of life based on hearing. The quality of life associated with hearing loss was unpleasant, motor ability, anxiety/depression, and everyday life affected in order of self management. And factors having an effect on the quality of life of the study subjects were found to be gender, elderly, unmarried, low hearing, low household income, absence of economic activity, and low teaching standards. Conclusion: The conclusion is that strengthening education for realistic management and prevention rather than treatment for unconditional hearing impairment will overcome low self esteem and loneliness and alleviate any uncomfortable life that people with hearing loss give. It is expected to be possible.