• Title/Summary/Keyword: Chongju

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A Study on Pollution Levels and Source of Polychlorinated Biphenyl (PCB) in the Ambient Air of Korea and Japan (한국과 일본의 환경대기 중 폴리염화비페닐(PCB)의 농도수준 및 발생원 해석에 관한 연구)

  • Kim, Kyoung-Soo;Song, Byung-Joo;Kim, Jong-Guk;Kim, Kyeo-Keun
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.2
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    • pp.170-176
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    • 2005
  • This study was conducted to investigate the level of PCBs and distribution of PCB congeners in the ambient air of Korea and Japan. The source of PCBs were also studied by a statistical method. The TEQ concentration of PCB in the ambient air of Korea and Japan were between 0.003 and $1.01\;pgTEQ/m^3$(mean value : $0.22\;pgTEQ/m^3$) and between 0.002 and $0.014\;pgTEQ/m^3$ (mean value: $0.007\;pgTEQ/m^3$), respectively. The ambient air of industrial area of Korea showed a fluctuation in PCB concentration than other sampling area. The isomer distribution patterns in the ambient air was more or less similar in all sampling places. In addition, highly chlorinated homologues ($7{\sim}10CB$) were detected in the only Korea industrial area. This observation suggests that there is a possibility of specific source of PCBs in the industrial area. The source identification of PCB in ambient air was performed using multivariate statistical analysis(principal component analysis). As a result, it is estimated that the Korean ambient air was more influenced by combustion process than the ambient air of Japan and also the effect of PCB commercial products was relatively a small.

Physiological Characteristics of Resistant Starch (HI-MAIZE DIET) Fortified with Other Dietary Fiber Components (식이섬유의 기능이 강화된 저항전분 (HI-MAIZE DIET)의 생리적 특성)

  • Choi, Yang-Mun;Oh, Sung-Hoon;Yu, Kwang-Won;Shin, Kwang-Soon;Ra, Kyung-Soo;Park, Chul-Soo;Kim, Kyung-Mi;Suh, Hyung-Joo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.3
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    • pp.351-355
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    • 2005
  • This study was performed to investigate the influences of resistant starch (HM: HI-MAIZE) and HM-D (HI-MAIZE DIET) fortified with D-factor (consisted of Psyliium husk, polydextrose and hydrocitric acid) on the glucose and bile acid absorption and production of short chain fatty acids (SCFA). HM-D absorbed more glucose and bile acid than did HM. The glucose transport of HM and HM-D against dialysis membrane showed 77% and 68% for 4h, respectively. After 24h, bile acid transport of HM and HM -D showed 65% and 62.3%, respectively. The HM and HM-D produced 217.8 mM and 264.0mM of SCFA, respectively. The production of butyric acid in HM-D (32.7mM) showed higher than that of HM (26.9mM). The addition of D-factor to HM increased the physiological function of dietary fiber through the glucose and bile acid absorption and production of SCFA.

CALORIMETRIC INVESTIGATION OF SULFUR VULCANIZATION OF NATURAL RUBBER

  • Paik, Nam-Chul;Choi, Sei-Young;Suh, Won-Dong
    • Elastomers and Composites
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    • v.21 no.1
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    • pp.13-19
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    • 1986
  • The effects of several vulcanizing accelerators on the determination of kinetic parameters of natural rubber vulcanizate was studied by DSC. Kinetic parameters were determined by means of the calculation procedures of Borchardt-Daniels and Oscillating Disk Rheometer (ODR) cure curve analysis, using both DSC exothermal thermogram and ODR cure curve. In order to examine the credibility in the DSC method the same compound which was und for DSC method was used for the comparison with the results of ODR data. Upon this method, kinetic rate constant (k), and Arrehenius parameter (Ea, ko, n) have been determined for rubber compounds via a new method using DSC thermogram and ODR cure curve. In the comparison of DSC and ODR results, kinetic parameters has shown good agreements between two results. Consequently, from the present studies, it is shown that the DSC thermoanalytical method can provide an alternate new method of kinetic study of rubber vulcanization.

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Development of Forms for Cold Weather Concrete by Combination of Insulation (단열재 조합에 의한 한중콘크리트용 거푸집 개발)

  • Han, Cheon-Goo;Oh, Seon-Kyo;Sin, Dong-An;Kim, Kyoung-Min
    • Journal of the Korea Concrete Institute
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    • v.15 no.3
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    • pp.392-399
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    • 2003
  • This paper discusses the validities of insulating curing of cold weather concreting at early stage by applying insulation forms. Tests were carried out using modified insulating form combining existing insulating form and various other insulations in order to develop improved insulation form. Temperature history of concrete using various insulating forms and insulation was measured to determine most effective combination of insulting form. According to results, as for the wall form, under the curing temperature of $-10^{\circ}C$, the temperature of concrete using Euro form drops sharply before 24 hours and lasts below $0^{\circ}C$ for 7 hours. The temperature of concrete using the form combining Polypropylene panel, styrofoam and plywood panel keep above $0^{\circ}C$. And, it is confirmed that the form mentioned above has a favorable effects on enhancing strength development of concrete and the cost to make the forms shows more reasonable than that of existing forms. However, as for the combination methods of insulation form for slab, which is composed of insulating form at the bottom of slab and various surface curing materials at the top of slab, in case of exposed condition at the top of slab, temperature history of concrete goes below $0^{\circ}C$ after 10 hours. In case of the combination of vinyl sheet and curing blanket, it drops below $0^{\circ}C$ after 42 hours. However, in case of the combination of vinyl, styrofoam and curing blanket, it does not go below $0^{\circ}C$ until 55 hours. Accordingly, compared to the case of exposure and the combination of vinyl and curing blanket, it indicates that the combination mentioned above has more effective insulating performance.

The Development of "Non-Eo Counseling Program" for Elementary School Students (초등학생용 논어상담프로그램 개발)

  • Lee, Jung-Hee
    • The Korean Journal of Elementary Counseling
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    • v.10 no.1
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    • pp.77-94
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    • 2011
  • The purpose of this study was to think about 'the nature of the mind' through the extraction of contents related to the 'mind' which is contained in "Non-eo(the Analects of Confucius)" and to devise a 'Non-Eo' counseling program intended for elementary school students by finding out counseling elements related to the growth of the mind. The 'Non-Eo' counseling program developed in this study was 10 lessons of forty minutes each and divided the group counseling procedure into three phases as introduction, progress, and wrap-up. The subjects of this study were 40 elementary school students in upper grades in a specific county: 20 students in the control and experimental group respectively. The 'Non-Eo' counseling program was applied to the experimental group twice a week for five weeks and it was not applied to the control group. Two measurement tools were used in order to verify the effects: the self-esteem measurement test adopted by Gong, Tae-Su(1998) which was originated from the selfesteem measurement test for children developed by Coopersmith(1967) and the friendship measure test adopted by Jo, Seong-rye(2001) which originated from the friendship measure test developed by Furman and Bierman(1983). The results were as follows; Firstly, there was a significant difference between the growth of self-esteem of the students in the experimental group and that in the control group; in general, the p-value of the experimental group was .032. Secondly, there was a significant difference between the growth of friendship of the students in the experimental group and that in the control group; in general, the p-value of the experimental group was .046. The fact that this study carried out a new counselling approach called 'Non-Eo' counseling based on the contents related to 'the growth of the mind' in "Non-eo" is of great significance.

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Zygotic Expression of c-myc Gene in Mouse Early Embryos: Functional Role of c-myc Promoter (생쥐 초기배아에서 c-myc Proto-Oncogene Promoter의 기능적 활성화)

  • Park, Ki-Soo;Kang, Hae-Mook;Shim, Chan-seob;Sun, Woong;Kim, Jae-man;Lee, Young-Ki;Kim, Kyung-jin
    • The Korean Journal of Zoology
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    • v.38 no.4
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    • pp.550-556
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    • 1995
  • The c-myc proto-oncogene is Involved In the control of normal cell proliferation and differentiation of many cell lineages. Although it has heen suggested that c-myc may play an important role in the mammalian early development, it Is unclear whether the embryonic c-myc mRNA is originated from zygotic gene expression or stored maternal message. Thus, we have construded expression vectors, In which the 5, flanking sequences including c-myc promoter region and a large non-coding exon I are fused 'sith E. coli lacZ gene that encedes $\beta$-galactosldase as a reporter. As c-myc exon I contains a modulatory sequence, we designed t, vo types of vectors (pcmyc.Gall and pcmyc-Ga12) to examine the role of exon I in c-myc expression. The former contains the complete exon I and the later has a deletion in 40 bp of modulator sequence located In the exon I of c-myc These vectors were microInjected into fertilized one-cell embryos and $\beta$-galactosidase activity was examined by X-gal staining during early embryogenesis. $\beta$-galactosidase activity derived from c-myc promoter was decreased at two-cell stage. The expression level directed by pcmyc- Ga12 was similar to that of pcmyc-Gal1, indicating that the medulatory sequence in exon I may not be Involved at least In the regulation of embryonic c-myc expression. In summary, the present study indicates that the c-myc promoter is functional at the early stage embryo, and the regulation of c-myc expression is under the control of "zygotic" clock of preimplantation mouse embryos.e embryos.

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A Study on Safe use of Pesticides and Pesticidal Poisoning Among the Korean Farmers (농약안전사용(農藥安全使用) 및 중독경험(中毒經驗)에 관(關)한 연구(硏究))

  • Yi, Taek-Ku
    • Journal of agricultural medicine and community health
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    • v.6 no.1
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    • pp.13-24
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    • 1981
  • This study was conducted with 478 farm households located in Pyongtaek Gun of Gyonggi Do, Chongju City and Chongwon Gun of Chung Buk Do, and Hongchon Gun of Gangwon Do for the period of 10, September through 20, October 1980. It dealt with general features of the farmhouseholds, their practices of handling and using pescides, and relationship between safe use of pesticides and poisoning experiences. The results of the study are summarized as follows: 1. Of the total, 63.2% purchased pesticides mainly through the Agricultural Coops, and 95.4% transported them home separately from other goods. 2 Pesticides were sold contained mainly in glass bottles and paper bags. 3. Mixing of the respodents (87.5%) stored pesticides in sheds, warehouses and boxes. 4. Mixing containers and measuring tools were not used by the majority of the group studied. This indicates that there exist serious problems of safety and accuracy with regard to use of pesticides. 5. As to pesticide protective devices, gloves, respirators, goggles and boots were not used in general. Even in case of using them, their quality was not satisfactory. 6. Among the interviewees, 4.2% did not read pesticide label, 33.9% did not wash immediately when pesticide was spilled on the skin, 48.4% did not care the wind direction during pesticide application, and 17.0% did not wash hands when smoking a cigarette while pesticide is being handled. 7. Of the total, 40.4% were found to harvest vegetables within 10 days from the date of pesticide application, which indicates their unawareness of possible hazards by pesticide residues. 8. Empty pesticide containers or bags were not properly disposed of by majority of the respondents. Furthermore, impacts on the environment by the misuse or abuse of pesticides were not understood by 67.6% 9. Of the interviewees, 48.7% were found to have not received instructions on safe use of pesticides. 10. The rate of pesticidal poisoning experience was about 28.0% if minor symptoms excluded, and it rose to about 44.0% if included. Meanwhile, the rate of pesticidal poisoning tends to increase with the size of farm. 11. The study failed to show a statistically significant relationship between the rate of pesticidal poisoning and use of mixing container and/or measuring tools. However, use of gloves showed a statistical significance on the rate of pesticidal poisoning. 12. Among the poisoned cases, 19.0% were cared for in either hospitals or clinics.

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A Study on the Indexes and Properties of Mechanical Weathering to Granite Distributed in Korea (화강암의 풍화산물에 대한 기계적 풍화지수의 특성에 관한 연구)

  • Rheem, Chong-Ho
    • Journal of the Korean Geographical Society
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    • v.28 no.2
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    • pp.99-111
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    • 1993
  • The transformation of rocks into unconsoli-dated debris is the prime geomorphic processes including weathering and soil forming process. In these processes, rocks tend to be unconsol-idated debris with small particles. Particularly, typical granite is more likely affected by weathering, since the rock consists of quartz, feldspar and mica that can be easily coarse-grained and well jointed without bedding. The purposes of this study are to clarify the index and properties of mechanical weathering that contributed to transformation of granite distributed in Korea. A total of seventy-three samples of weathering products of granite in Korea were collected during the three-year period, March 30, 1989 to February 21, 1992. The prticle analysis was performed for clay, silt and sand using Sieve and Hydrometer. The results of the analysis are as the followings: First, soil textures in the study area are included seven categories of textures as C, CL, SCL, Sil, SL, LS, and S. Among these textures, the most frequent soil texture were SL, S and SCL in order. Second, the weathering products of granite are crumbled by weathering and hydrothermal. Clay texture consisted of fine materials seems to be influenced by hydrothermal, while Sand texture composed of coarse materials, seems to be significantly influenced by weathering. Third, the index of mechanical weathering by region indicates that Hawngdeung(1) is the lowest as 2.37 and the index by soil texture shows that Clay texture is the lowest as 2.46. Forth, the regression analysis of MW showes that sand/clay variable is the most significant variable. Finally, pedochemical weathering is prevailed on the clayey gruss and geochemical weathering is on the gruss and shattering is on the weathered rock, strongly, but the fine materials in some sites were formed by argillation of hydrothermal.

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Development of an EEG Software for Two-Channel Cerebral Function Monitoring System (2채널 뇌기능 감시 시스템을 위한 뇌파 소프트웨어의 개발)

  • Kim, Dong-Jun;Yu, Seon-Guk;Kim, Seon-Ho
    • Journal of Biomedical Engineering Research
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    • v.20 no.1
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    • pp.81-90
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    • 1999
  • This paper describes an EEG(electroencephalogram) software for two-channel cerebral function monitoring system to detect the cerebral ischemia. In the software, two-channel bipolar analog EEG signals are digitized and from the signals various EEG parameters are extracted and displayed on a monitor in real-time. Digitized EEG signal is transformed by FFT(Fast Fourier transform) and represented as CSA(compressed spectral array) and DSA(density spectral array). Additional 5 parameters, such as alpha ratio, percent delta, spectral edge frequency, total power, and difference in total power, are estimated using the FFT spectra. All of these are effectively merged in a monitor and displayed in real-time. Through animal experiments and clinical trials on men, the software is modified and enhanced. Since the software provides raw EEG, CSA, DSA, simultaneously with additional 5 parameters in a monitor, it is possible to observe patients multilaterally. For easy comparison of patient's status, reference patterns of CSA, DSA can be captured and displayed on top of the monitor. And user can mark events of surgical operation and patient's conditions on the software, this allow him jump to the points of events directly, when reviewing the recorded EEG file afterwards. Other functions, such as forward/backward jump, gain control, file management are equipped and these are operated by simple mouse click. Clinical tests in a university hospital show that the software responds accurately according to the conditions of patients and medical doctors can use the software easily.

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Ultrastructure of Gametes in the Three-spine stickleback, Gasterosteus aculeatus aculeatus (큰가시고기 배우자의 미세구조)

  • Deung, Young-Kun;Kim, Dong-Heui;Reu, Dong-Suck
    • Applied Microscopy
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    • v.29 no.2
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    • pp.177-187
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    • 1999
  • Ultrastructure of gametes in the three-spine stickleback, Gasterosteus aculeatus aculeatus was observed, utilizing light, scanning and transmission electron microscopes. The egg of three-spine stickleback is spherical and demersal type. The eggs are highly adhesived to each other but not to substrates. There are many oil droplets in vitelline membrane. The outer surface of egg envelope is arranged by mushroom-like structures and pore canals. The egg have a micropyle, sperm entry site, in the area of the animal pole. The egg envelope consists of three layers, an outer layer with high electron density, a middle layer consisting two layers and an inner layer consisting of 16 to 20 layers. In the fertilized egg envelope, the molecular weights of these components ranged from 14 kDa to 205 kDa. The molecular weights of nam protein bands are 19.4 kDa, 36.7 KDa, 39.4 kDa, 42.9 kDa, 46.1 kDa and 53.0 kDa. The head of spermatozoa is spherical shape and the acrosome is absent. The mitochondria in midpiece are arranged from one to three layers and separated from the axoneme by the cytoplasmic canal. The tail has two lateral fins and the axoneme is of the 9+2 structure.

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