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Analysis on the Characteristics of Nonpoint sources during the Precipitation in Residential Area (강우 시 주거지역에서의 비점오염원 유출특성 분석)

  • Kwon, Heongak;Im, Toehyo;Na, Seungmin;Lee, Chunsik;Cheon, Seuk
    • Journal of Wetlands Research
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    • v.17 no.4
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    • pp.391-401
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    • 2015
  • In this study, divided into small category groups for the residential area it was carried out monitoring for the runoff during precipitation. Based on the results analyzed according to the nonpoint sources Housing leakage characteristics. Analysis of the rainfall runoff and concentration of each type of exclusive detached house with apartments, in the majority of precipitation types runoff concentrations were higher in early. In the case of a difference of two points per runoff rate rainfall it was largely investigation. The average runoff is estimated loadings of BOD $101.1kg/km^2$, SS $232.2kg/km^2$, T-N $18.2kg/km^2$, T-P $2.0kg/km^2$ detached house case, if the apartment was estimated at point BOD $108.82kg/km^2$, SS $329.18kg/km^2$, T-N $57.67kg/km^2$, T-P $4.21kg/km^2$. The average EMCs is BOD BOD 6.6 mg/L, SS 12.8 mg/L, T-N 1.518 mg/L, T-P 0.099 mg/L detached house case, if the apartment was estimated at point BOD 6.3 mg/L, COD 11.2mg/L, SS 14.5 mg/L, T-N 3.1 mg/L, T-P 0.2 mg/L. The initial 30 percentage calculated based on the initial results, the total flow of 30% if the outflow of detached house showed a net percentage difference to T-P 1.04 > T-N 0.97 > BOD 0.90 > SS 0.80. The apartment area showed the percentage difference in the water quality in the order of BOD 1.49 > T-P 1.40 > SS 1.30 > T-N 0.96 per item.

Potential Antitumor $\alpha$-Methylene-$\gamma$-butyrolactone-Bearing Nucleic Acid Base. 3. Synthesis of $5^1$-Methyl-$5^1$-[(6-substituted-9H-purin-9-yl)methyl]-$2^1$-oxo-$3^1$-methylenetetrahydrofurans

  • Kim, Jack-C.;Kim, Si-Hwan;Kim, Ji-A;Choi, Soon-Kyu;Park, Won-Woo
    • Archives of Pharmacal Research
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    • v.21 no.4
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    • pp.458-464
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    • 1998
  • Search for a new $\alpha$-methylene-$\gamma$-butyrolactone-bearing 6-substituted purine as a potental antitumor agent has led to synthesize seven, hitherto unreported, $5^1$-Methyl-$5^1$-[(6-substituted-9H-purin-9-yl)methyl]-$2^1$-oxo-$3^1$- methylenetetrahydrofurans (H, Cl, l, $CH_3$, $NH_2$, SH, >C=O) (6a-g). These include $5^1$-Methyl-$5^1$-[(9H-purin-9-yl)methyll-$2^1$-oxo-$3^1$ -methylenetetrahydrofurans (6a), $5^1$-Methyl-$5^1$-[(6-chloro-9H-purin-9-yl)methyl]-$2^1$-oxo-$3^1$-methylenetetrahydr ofurans (6b), $5^1$-Methyl-$5^1$-[(6-chloro-9H-purin-9-yl) methyl]-$2^1$-oxo-$3^1$-methylenetetrahydrofurans (6c), $5^1$-Methyl-$5^1$-[(6-methyl-9H-purin-9-yl) methyl]-$2^1$-oxo-$3^1$-methylenetetrahydrofurans (6d), $5^1$-Methyl-$5^1$-[(9H-adenin-9-yl)methyll-$2^1$-oxo-$3^1$-methylenetetrahydrofurans (6e), $5^1$-Methyl-$5^1$-[(6-mercapto-9H-purin-9-yl) methyl]-$2^1$-oxo-$3^1$-methylenetetrahydrofurans (6f) and $5^1$-Methyl-$5^1$-[(9H-hypoxanthin-9-yl)methyll-$2^1$-oxo-$3^1$-methylenetetrahydrof urans (6g) which were made by the Reformatsky-type reaction of ethyl $\alpha$-(bromomethyl) acrylate with the corresponding (6-substituted-9H-purin-9-yl)-2-propanone intermediates (5a-g). These ketone intermediates 5a-g, 1-(9H-purin-9-yl)-2-propanone (5a), 1-(6-chloro-9H-purin-9-yl)-2-propanone (5b), 1-(6-iodo-9H-purin-9-yi)-2-propanone (5c), 1-(6-methyl-9H-purin-9-yl)-2-propanone (5d), 1-(9H-adenin-9-yl)-2-propanone (Se), 1-(6-mercapto-9H-purin-9-yl)-2-propanone (5f), and 1-(9H-hypoxanthin-9-yl)-2-propanone (5g) were directly obtained by the alkylation of the 6-substituted purine bases with the chloroacetone in the presence of $K_2$$CO_3$ (or NaH) under DMF (or DMSO). The preliminary in vitro cytotoxcity assay for the synthetic .alpha.-methylene-y-butyro-lactone compounds (6a-g) were determined against three cell lines (PM-3A, P-388, and K-562) and showed the moderate antitumor activity ($IC_50$ ranged from 1.4 to 4.3 $\mu\textrm{g}$/ml) with the compound $5^1$-methyl-$5^1$ -[(9H-hypoxanthin-9-yl)methyl]-$2^1$-oxo-$3^1$-methylenetetrahydrofuran (6g) showing the least antitumor activity.

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A Trend of Research in Community Health Nursing (지역사회간호학 관련 논문 연구동향 분석 -학회지 발표 논문을 중심으로-)

  • Lee, In-Sook;Kim, Yu-Na;Choi, Key-Won;Chin, Young-Ran
    • Research in Community and Public Health Nursing
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    • v.12 no.1
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    • pp.288-298
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    • 2001
  • This article makes an attempt to evaluate the extent of developing community health nursing knowledge and to suggest the direction of developing a body of knowledge henceforth through the results of analysis for contents and outcomes of all literatures. which have been published in the Journal related to community health nursing. Refer to the following for the result of this article. 1. The total number of literatures analyzed amounted to 100 pieces in Journal of community health nursing society. 78 in Journal of industrial nursing society, 134 in Journal of school health society. 40 in Journal of home care nursing society. 2. Journal of community health nursing society Health needs and educational-behavioral diagnoses, which are more concrete nursing assessments and diagnoses. formed the main current(54%) of articles published in Journal of community health nursing society since 1992. There was a quantitative growth as well as a qualitative advance. Through a classification by the type of a body of knowledge. It was found that the knowledge providing nursing practice with bases, commanded an overwhelming majority(71.8%). Also, Researches on systemic supports for nursing practice are showing a tendency to increase. 3. Journal of industrial nursing society 52.6% of research papers presented in Journal of industrial nursing society dealt with health problem of workers. assessment of risk factors, diagnosis of health behaviors. Because of the beginning of an industrial nursing, the domain of nursing management to establish the role and task, work condition, training. documentary system made up 23 percent of research, subjects. A knowledge providing nursing practice with bases have a majority, 69.2%. In addition. the subject concerning a systemic support and quality assurance was scarce but continuously presented. 4. Journal of school health society The major point of this journal is the identification of health problems and risk factors which belong to assessment and diagnosis domain(56.8%) regardless of year, Because of the interdisciplinary characteristic. The knowledge on quality assurance of nursing practice is relatively rare. But, articles related to a systemic support is plentiful. 5. Journal of home care nursing society In its infancy, there was a large number of papers concerning need assessment and diagnosis, Comparing others, this journal has introduced a good many of articles related to program management. delivery system. service fee, etc that belong to domain of systemic support for nursing practice. 6. It is showing definitely that quantity and extent of research have grown for a short period. See the analysis in terms of nursing process, studies related to the domain of assessment and diagnosis command an absolute majority regardless of kinds of journal. Although articles referring to program management and implementation is increasing in number, it is scarce to evaluate a nursing program and grope for an improvement. Also, program development based on a theoretical framework is little. Therefore much more scientific effort to ensure profession should be executed. 7. In the methodological aspect, longitudinal study needs to be carried out so that we could show the evidence based nursing theory. To develop a more general theory, we have to conduct a study of various subjects and improve a validity of tools through a repeat test. In addition, the effort for interdisciplinary cooperation is needed.

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Blood Pressure Cuff Bladders Tailored For Koreans (한국인 맞춤형 혈압계 커프 블래더)

  • Hwang, Lark Hoon;Park, Woo Sung;Na, Seung Kwon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.9
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    • pp.822-829
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    • 2013
  • Hypertension is one of the most common clinical diseases, with an increasing prevalence globally. Hypertension triggers various harmful consequences and affects multiple organs. Life-long care may be required in some cases. According to the Korea Center for Disease Control and Prevention, the prevalence of hypertension is gradually increasing. A 2011 survey revealed that 28.9% of Korean adults had hypertension. The prevalence rates were slightly higher among men than women. Accurate measurement of blood pressure(BP) is crucial to classify patients, to identify BP-related risks, and to inform correct treatment. For accurate blood pressure measurement, the use of a cuff bladder size appropriate for the mid-upper arm circumference(MUAC) is essential. Incorrect sized cuff bladder is one of the main causes of equipment error affecting sphygmomanometer accuracy. When commercial sphygmomanometers were examined, the cuff bladders differed from the dimensions specified in the ISO 81060-1:2007 standards. Undercuffing is responsible for a spurious overestimation of BP in patients with large arms leading to overdiagnosis of hypertension, whereas overcuffing (that is, use of relatively large cuffs with small arms), may be responsible for an opposite problem, leading to erroneous underestimation of BP levels. The cuff bladder sizes recommended by the American Heart Association(AHA) are an arm circumference(AC) of 17-25 cm for small-sized adults, AC of 24-32 cm for adults, AC of 32-42 cm for normal-sized adults, and AC of 42-50 cm for obese adults. In contrast, the AC of Korean adults ranges from 23-31 cm, belonging to a single type of adult bladder. Three types of bladders are necessary for Korean adults with an AC of 23-31cm. Hospitals often use one or two differently-sized Western cuffs for adult patients, which can yield inaccurate BP determinations. Cuff bladders with dimensions based on anthropometric reference data obtained from Koreans will aid hospitals to measure BP more accurately.

Absorption of Carbon Dioxide into Aqueous Potassium Salt of Serine (Serine 칼륨염 수용액의 이산화탄소 흡수특성)

  • Song, Ho-Jun;Lee, Seung-Moon;Lee, Joon-Ho;Park, Jin-Won;Jang, Kyung-Ryong;Shim, Jae-Goo;Kim, Jun-Han
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.7
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    • pp.505-514
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    • 2009
  • Aqueous potassium salt of serine was proposed as an alternative $CO_2$ absorbent to monoethanolamine (MEA) and its $CO_2$ absorption characteristics were studied. The experiment has been conducted using screening test equipment with NDIR type gas analyzer and vapor-liquid equilibrium apparatus. $CO_2$ absorption/desorption rate and net amount of $CO_2$ absorbed in cyclic process are the criteria to assess the $CO_2$ absorption characteristics in this study. Effective $CO_2$ loading of potassium salt of serine and MEA are 0.425 and 0.230 respectively. Cyclic capacities are 0.354 and 0.298 for potassium salt of serine and MEA. The absorption rate of the potassium serinate decreased sharply at $CO_2$ loading is 0.1 and were maintained approximately at half of MEA. To enhance the absorption rate of aqueous potassium salt of serine, small quantities of rate promoters, namely piperazine and tetraethylenepentamine were blended, so that rich $CO_2$ loading were increased by 13.7% and 18.7% respectively. The rich $CO_2$ loading of potassium salt of serine was 29.2% and 35.0% higher than those of aqueous sodium and lithium salt of serine, respectively. The absorption rate of potassium salt of valine and isoleucine which have similar molecular structures to serine were lower than that of serine because of the presence of bulky side group. Precipitation phenomena during $CO_2$ absorption were discussed by the aid of literatures.

A Numerical Study for Effective Operation of MSW Incinerator for Waste of High Heating Value by the Addition of Moisture Air (함습공기를 이용한 고발열량 도시폐기물 소각로의 효율적 운전을 위한 수치 해석적 연구)

  • Shin, Mi-Soo;Shin, Na-Ra;Jang, Dong-Soon
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.2
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    • pp.115-123
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    • 2013
  • Stoker type incinerator is one of the most popular one used as municipal solid waste (MSW) incineration because, in general, it is quite suitable for large capacity and need no preprocessing facility. Nowadays, however, since the combustible portion of incoming MSW increases together with the decrease of the moisture content due to prohibition of directly burying food waste in landfill, the heating value of waste is remarkably increasing in comparison with the early stage of incinerator installation. Consequently, the increased heating value in incinerator operation causes a number of serious problems such as reduction of waste amount to be burned due to the boiler heat capacity together with the significant NO generation in high temperature environment. Therefore, in this study, a series of numerical simulation have been made as parameters of waste amount and the fraction of moisture in air stream in order to investigate optimal operating condition for the resolution of the problems associated with the high heating value of waste mentioned above. In specific, a detailed turbulent reaction flow field calculation with NO model was made for the full scale incinerator of D city. To this end, the injection method of moisturized air as oxidizer was intensively reviewed by the addition of moisture water amount from 10% and 20%. The calculation result, in general, showed that the reduction of maximum flame temperature appears consistently due to the combined effects of the increased specific heat of combustion air and vaporization heat by the addition of water moisture. As a consequence, the generation of NOx concentration was substantially reduced. Further, for the case of 20% moisture amount stream, the afterburner region is quite appropriate in temperature range for the operation of SNCR. This suggests the SNCR facility can be considered for reoperation. which is not in service at all due to the increased heating value of MSW.

Studies on the RNA nucleotide composition of egg, worm body, pupa and silk-gland(posterior) of Bombyx mori, and spinning gland of spider (가잠(家蠶)의 충체(蟲體), 용체, 잠란(蠶卵) 및 견사선(絹絲腺)(후부(後部))과 지주(蜘蛛) 방적선(紡績腺) RNA의 nucleotide 조성(組成)에 관(關)한 연구(硏究))

  • Kim, Hyeong-Su
    • Applied Biological Chemistry
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    • v.5
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    • pp.7-21
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    • 1964
  • 가잠(家蠶)(Bombyx mori)의 잠체(蠶體), 용체 및 견사선(絹絲腺)(후부(後部))에서 phenol법(法)으로 RNA를 추출(抽出)하여 RNA의 nucleotide 조성(組成)(mole ratio)을 살피는 한편, 견사선(絹絲腺)(후부(後部))에서 초원심법(超遠沈法)으로 r-RNA, s-RNA를 분리(分離)하여 이에 대(對)한 nucleotide조성(組成)을 조사(調査)하고 또 가잠견사선(家蠶絹絲腺)과 비교(比較)할 목적(目的)으로 거미 방적선(紡績腺)의 t-RNA를 분리(分離)하여 nucleotide성분(成分)을 측정(測定)하여 다음과 같은 결과(結果)를 얻었다. 1) 잠란(蠶卵)에 있어서 이것을 마수(磨粹), 탈지(脫脂) 후(後) lysozyme을 작용(作用)시키고 10% NaCl용액(溶液)으로 가열(加熱) 추출(抽出)하는 새방법(方法)을 고찰(考察)하여 RNA의 추출(抽出)이 극난(極難)한 잠란(蠶卵)에서 RNA를 분리(分離)하는데 성공(成功)하였다. 2) 가잠란(家蠶卵), 잠체(蠶體), 용체 및 견사선(絹絲腺)(후부(後部))의 t-RNA nucleotide 조성(組成)은 다음과 같다. 시료(試料) $\frac{G+C}{A+U}$ $\frac{G+U}{A+C}$ $\frac{Pu}{Py}$ 가잠란(家蠶卵)의 RNA 1.14 1.24 0.99 가잠체(家蠶體)의 RNA 1.40 1.36 0.80 용체의 RNA 1.40 1.33 1.35 후부견사선(後部絹絲腺)의 RNA 1.05 1.32 1.15 이로서 잠체(蠶體). 용체 및 견사선(絹絲腺)의 Pu/Py는 각각(各各) 차이(差異)가 있으나 G+U/A+C는 3자간(者間)에 1.3의 거이 동일(同一)한 수치(數値)를 보여주고 있다. G+C/A+U는 잠체(蠶體)와 용체에 있어서 동일(同一)하나 견사선(絹絲腺)의 그것과는 차이(差異)가 있다. 한편 잠란(蠶卵)에 있어서는 Pu/Py, G+C/A+U, G+U/A+C가 각각(各各) 잠체(蠶體), 용체 및 견사선(絹絲腺)에 있어서와 현저(顯著)한 차이(差異)를 보여주고 있다. G+C/A+U가 1.3이나 되는 RNA의 base ratio를 가진 생물(生物)에 관(關)해서는 아직 보고(報告)된 바 없고 다만 본논문(本論文)의 가잠(家蠶)에 관(關)한 RNA와 속편(續編)인 각종(各種) 패류(貝類) RNA의 nucleotide 조성(組成)에서 모두 1.3에 가까운 수치(數値)를 보여주고 있다. 3) 견사선(絹絲腺)(후부(後部)) t-RNA와 거미 방적선(紡績腺)의 t-RNA의 nucleotide molar ratio 및 견사선(絹絲腺)의 r-RNA, s-RNA nucleotide 조성(組成)은 다음과 같다. 재료(材料) $\frac{G+C}{A+U}$ $\frac{G+U}{A+C}$ $\frac{Pu}{Py}$ 가잠견사선(家蠶絹絲腺)(후부(後部)의 t-RNA 1.05 1.32 1.15의 r-RNA 1.12 1.30 1.20의 s-RNA 1.55 1.33 0.65 지주방적선(蜘蛛紡績腺)의 t-RNA 1.35 1.24 1.16 즉(卽) 가잠견사선(家蠶絹絲腺)(후부(後部))과 거미방적선(紡績腺)의 t-RNA nucleotide 조성(組成)은 Pu/Py가 1.15와 1.16으로서 거이 동일(同一)하지만 G+C/A+U, G+U/A+C에 차이(差異)가 있음을 보았다. 한편 가잠견사선(家蠶絹絲腺)(후부(後部)) r-RNA와 s-RNA의 Pu/Py와 G+C/A+U는 현저(顯著)한 차이(差異)가 있고, G+U/A+C에 있어서는 1.3으로서 거이 동일(同一)한 수치(數値)를 보여주고 있다. 4. 이상(以上)과 같이 잠체(蠶體)에 관(關)한 RNA의 nucleotide 조성(組成)은 소위(所謂) GC-type로서, 현재(現在)까지 문헌(文獻)에 보고(報告)된 각종(各種) 생물(生物)의 RNA의 base ratio에 관(關)하여 비교(比較) 검토(檢討)하였으며, RNA의 nucleotide ratio의 차이(差異)의 의의(意義)에 대(對)하여 고찰(考察)하였다.

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Genotype Frequency of Human Papillomavirus Determined by PCR and DNA Sequencing in Korean Women

  • Lee, Kyung-Ok;Seong, Hye-Soon;Chung, Soo-Jin;Jung, Na-Young;Lee, Hye-Jung;Kim, Kyung-Tae
    • Korean Journal of Clinical Laboratory Science
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    • v.38 no.2
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    • pp.99-104
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    • 2006
  • Human Papilloma viruses (HPVs) are etiological agents for cervical cancer and are classified into low- and high-risk categories. The aim of this study was to determine the frequency of the HPV genotype in the HPV screening test of Korean women using PCR-direct sequencing. Consensus primers of L1 legion were used for the amplification of HPV DNA and the PCR products (450 bps) obtained were analyzed by automatic sequencing. Sequences were compared with those in GenBank by using the BLAST program. Cervical swab samples of 3,978 women (20-73 years) were tested and the average age was 37.6 years. In this study, 1,174 samples were HPV positive out of 3,978 cervical swab samples screened (29.5%) and 136 samples (11.6%) showed a double infection. A total of 1,310 HPV genotypes were analyzed. The HPV positive rate was the lowest in the 20 years group (69.5%) and most of the samples of the > 60 years group were found HPV positive. Among thirty seven different HPV types identified by sequencing, 21 were HPV high risk types and 16 HPV low risk types were 69.8% (914/1,310) and 26.0% (340/1,310), respectively. In HPV high-risk types, 16 (13.21%), was the most frequently found. HPV 53 (9.62%) and 58 (9.24%) were also frequently found. This group was followed by HPV types 70 (5.50%), 33 (4.73%), 66 (4.20%), 18 (4.05%), 52 (4.05%), 31 (3.97%) and 56 (3.51%) in descending order of frequency. Among HPV low-risk types, 62 (4.20%), 6 (3.59%), 81 (3.59%), 84 (3.51%), and 11 (2.6%) were frequently found. In conclusion, PCR-direct sequencing could be used for quick and reliable typing of known and novel HPVs from clinical specimens. This data could be useful for epidemiological study of HPV and it also allows type-specific follow-up of women who have been treated for cervical intraepithelial neoplasia.

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Effect of Green Tea Content on Static Bending Strength Performance of Hybrid Boards Composed of Green Tea and Wood Fibers (녹차-목재섬유복합보드의 정적 휨 강도성능에 미치는 녹차배합비율의 영향)

  • Park, Han-Min;Kang, Dong-Hyun;Lim, Na-Rea;Lee, Soo-Kyeong;Jung, Kang-Won;Kim, Jong-Chul;Cho, Kyeong-Hwan
    • Journal of agriculture & life science
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    • v.44 no.5
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    • pp.1-8
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    • 2010
  • In this study, eco-friendly hybrid composite boards were manufactured from green tea and wood fibers for application as interior materials with various functionalities of green tea and strong strength properties of wood fibers. In this relation, the effect of green tea content on the static bending strength performances of these green tea and wood fibers composite boards were investigated. Static bending strengths of hybrid composite boards were lower than those of control boards and decreased with the increase of green tea content. Also, the strength performances appeared to be somewhat different by resin type used for board manufacture. The hybrid composite boards manufactured from $E_1$ grade urea resin adhesive, which has higher molar ratio of formaldehyde to urea than that of $E_0$ grade one, were 1.08~1.53 times higher in bending modulus of elasticity (MOE) and 1.19~1.82 higher in modulus of rupture (MOR) than that manufactured from $E_0$ grade. And, the differences of MOE and MOR between hybrid composite boards manufactured from $E_0$ grade and $E_0$ grade urea resin adhesive increased with the increase of green tea content. In the case of hybrid composite boards manufactured from $E_1$ grade urea resin adhesive, the MOR was within 0.94~1.03 times the commercial medium density fiberboard. Thus, it was thought that eco-friendly hybrid composite boards with various functionalities and strong strength performances could be manufactured from green tea and wood fibers.

Seasonal and Inter-annual Variations of Sea Ice Distribution in the Arctic Using AMSR-E Data: July 2002 to May 2009 (AMSR-E 위성 데이터를 이용한 북극해빙분포의 계절 변동 및 연 변동 조사: 2002년 7월 ~ 2009년 5월)

  • Yang, Chan-Su;Na, Jae-Ho
    • Korean Journal of Remote Sensing
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    • v.25 no.5
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    • pp.423-434
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    • 2009
  • The Arctic environment is sensitive to change of sea-ice distribution. The increase and decrease of sea ice work to an index of globe warming progress. In order to predict the progress of hereafter earth global warming, continuous monitoring regarding a change of the sea ice area in the Arctic should be performed. The remote sensing based on an artificial satellite is most effective on the North Pole. The sea ice observation using a passive microwave sensor has been continued from 1970's. The determination of sea ice extent and ice type is one of the great successes of the passive microwave imagers. In this paper, to investigate the seasonal and inter-annual variation of sea-ice distribution we used here the sea ice data from July 2002 to May 2009 around the Arctic within $60^{\circ}N$ for the AMSR-E 12.5km sea-ice concentration, a passive microwave sensor. From an early analysis of these data, the arctic sea-ice extent has been steadily decreasing at a rate of about 3.1%, accounting for about $2{\times}10^5\;km^2$, which was calculated for the sea-ice cover reaching its minimum extent at the end of each summer. It is also revealed that this trend corresponds to a decline in the multi-year ice that is affected mainly by summer sea surface and air temperature increases. The extent of younger and thinner (first-year) ice decreased to the 2007 minimum, but rapidly recovered in 2008 and 2009 due to the dramatic loss in 2007. Seasonal variations of the sea-ice extent show significant year-to-year variation in the seasons of January-March in the Barents and Labrador seas and August-October in the region from the East Siberian and Chukchi seas to the North Pole. The spatial distribution of multi-year ice (7-year old) indicates that the perennial ice fraction has rapidly shrunk recently out of the East Siberian, Laptev, and Kara seas to the high region of the Arctic within the last seven years and the Northeast Passage could become open year-round in near future.