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Study on the Indoor Environment and Status of Facilities and Equipments of Home Economics Practice Rooms of Middle Schools in Jeju Special Self-Governing Province (제주특별자치도 중학교 가정실의 실내환경 및 시설.설비 현황에 관한 연구)

  • Park, Min-Hye;Kim, Bong-Ae
    • Journal of Korean Home Economics Education Association
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    • v.19 no.3
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    • pp.61-76
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    • 2007
  • The purpose of the study is to identify and understand problems existing in the middle school home economics practice rooms in Jeju Special Self-Governing Province. The findings are based on the examination and the analysis of the indoor environment and the condition of the facilities and equipment. Study method employs on-site research and a survey. The on-site research was conducted about temperature, humidity, intensity of illumination, and status of teaching instrument in 10 out of 41 middle schools in Jeju Special Self-Governing Province from August 16 to September 30, 2006. Meanwhile, the survey was implemented by mail for 95 teachers in charge of manual training and home economics education in 41 middle schools in Jeju from November 1 to 23, 2005. 64 questionnaires out of total 95 were collected, including those collected during the period of on-site research. Finally, 61 questionnaires which were effective among the answered ones were used for analysis. Collected materials were analyzed with the SPSS Win.12.0 program for frequency, percentile analysis. In conclusion, the study determines that the condition of the home economics practice rooms of the middle school in JSSGP in terms of temperature, humidity, lighting and ventilation is very inadequate. The structure of the practice room represents an inefficient work flow pattern. Further, the facilities and equipment are in a very poor condition because the facilities are old and the retention rate of teaching tools is low. Therefore, to address these problems, the study suggests that improvements on the facilities and equipment should be made and teaching tools should be replenished in accordance with the industry standard.

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Formation and Dissociation Kinetics of Zinc(II) Complexes of Tetraaza-Crown-Alkanoic Acids (Zinc(Ⅱ) Tetraaza-Crown-Allkanoic Acids 착물의 형성 및 해리 반응속도론)

  • Choi, Ki Young;Kim, Dong Won;Kim, Chang Suk;Park, Byung Bin;Choi, Suk Nam;Hong, Choon Pyo;Ryu, Hae Il
    • Journal of the Korean Chemical Society
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    • v.44 no.5
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    • pp.403-409
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    • 2000
  • The formation and dissociation rates of $Zn^{2+}$ Complexes with l,4,7,10-tetraaza-13,16-diox-acyclooctadecane-N,N',N",N'"-tetraacetic acid (1), 1,4,7,10-tetraaza-13,16- dioxacyclooctadecane-N,N',N",N'"-tetramethylacetic acid (2), and 1,4,7,10-tetraaza-13,16- dioxacyclooctadecane-N,N',N",N'"-tetrapropionic acid(3) have been measured by stopped-flow and conventional spectrophotometry. Observations were made at 25.0$\pm$0.1 $^{\circ}C$ and at an ionic strength of 0.10 M NaClO$_4$. The formation reactions of $Zn^{2+}$ ion with 1 and 2 took place by the rapid formation of an intermediate complex (ZnH$_3L^+$) in which the $Zn^{2+}$ ion is incompletely coor-dinated. This might then lead to be a final product in the rate-determining step.ln the pH range 4.76-5.76, the diprotonated (H2L2-) form is the kinetically active species despite of its low concentration. The stability con-stants (log$K_{(ZnH$_3$3$L^+$)}$) and specific water-assisted rate constants (koH) of intermediate complexes have been deter-mined from the kinetic data. The dissociation reactions of $Zn^{2+}$ complexes of 1,2, and 3 were investigated with $Cu^{2+}$ ions as a scavenger in acetate buffer. All complexes exhibit acid-independent and acid-catalyzed con-tributions. The effect of buffer and $Cu^{2+}$ concentration on the dissociation rate has also been investigated. The ligand effect on t dissociation rate of $Zn^{2+}$ complexes is discussed in terms of the side-pendant armsand the chelate ring sizes of the ligands.

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An Association of Changed Levels of Inflammatory Markers with Hematological Factors during One-time Aerobic Exercise in Twenty-aged Young Men (20대 젊은이들에 있어 1회성 유산소운동 시 염증 표지자와 혈액변인들 간의 상관관계)

  • Hyun, Kyung-Yae
    • Journal of Life Science
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    • v.19 no.11
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    • pp.1658-1665
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    • 2009
  • This study was carried out on thirty men to define the association of inflammatory markers with physiological factors on one-time aerobic exercise (for 15 min. Post-exercise interleukin-6 (IL-6), mean corpuscular hemoglobin concentration (MCHC), heart rate (HR), systolic blood pressure (SBP), and pulsatility and resistance index of middle cerebral artery (PI and RI, respectively) levels were elevated compared to those measured pre-exercise. Total leukocyte and platelet counts, high-sensitivity C-reactive protein (hs-CRP), free radical (FR), and low density lipoprotein cholesterol (LDL) levels tended to decrease after exercise. Pre-exercise IL-6 levels were positively correlated with pre-exercise SBP levels, while post-exercise IL-6 level was positively correlated with post-exercise PI and RI levels. Post-exercise, hs-CRP levels were negatively related to SBP and HR. Pre-exercise, FR levels were positively associated to SBP, DBP, and HR. Post-exercise FR levels were negatively related to the post-exercise blood flow velocity in middle cerebral artery. Pre-exercise erythrocyte indices (RBC, MCV, MCH, and MCHC levels) were in inverse proportion to pre-exercise IL-6 levels. Post-exercise FR levels were inversely related to post-exercise total leukocyte, lymphocyte, monocyte, and MCH levels. Pre-exercise $Mg^{++}$ levels were in inverse proportion to pre-exercise IL-6, hs-CRP, or FR levels. These findings suggest that one-time aerobic exercise offers a significant relationship between inflammatory markers and some biochemical markers or electrolytes. Further studies need to be carried out for investigation of differences between genders or age groups following one-time or regular aerobic exercise.

Environmental Geophysical Survey of Abandoned Landfills for Contamination Evaluation: A Case Study (불량 매립지 오염평가를 위한 지구물리 탐사 사례연구)

  • Lee, Sung-Soon;Lee, Jin-Yong;Yoon, Hee-Sung;Lee, Kang-Kun;Kim, Chang-Gyun;Yu, Young-Chul
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.5
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    • pp.463-471
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    • 2006
  • Electrical resistivity surveys were conducted at areas of abandoned landfills in Cheonan and Wonju. Geology and extent of leachate migration around the landfills were evaluated with collected resistivity data by 2-D and 3-D resistivity inverse modeling. The Cheonan landfill is located above the paddy fields and the resistivity survey lines were crossed to examine possible pollution at the paddy fields by leakage of the landfill leachate. In Wonju, the landfill and the downgradient paddy fields are divided by a concrete barrier wall. At the bottom of the landfill, there is a leachate settlement system, which has not been in operation. To evaluate leachate leakage into the paddy fields, a total of 4 survey lines were used. According to the resistivity survey results, the landfill leachate in Cheonan appeared to be restricted only within the interior of the landfill, not to migrate into the subsurface of the paddy fields. These results are well consistent with electrical conductivity values of groundwaters obtained from a periodic analysis of water qualities. In Wonju, however, it was inferred that the leachate emanating from the landfill migrated beneath the abandoned leachate settlement system and the leachate would reach the downgradient paddy fields. Low resistivity area was observed in the old reservoir area and it appeared to be derived from convergence of groundwater flows from the surrounding valley and the moist wet land. In addition, groundwater flow into the paddy fields occurs beneath the old reservoir embankment at depths of $7{\sim}8m$. This paper reports details of the resistivity surveys for the uncontrolled landfills.

Influence of Fine Aggregate Properties on Unhardened Geopolymer Concrete (잔골재 특성이 굳지 않은 지오폴리머 콘크리트에 미치는 영향)

  • Cho, Young-Hoon;An, Eung-Mo;Lee, Su-Jeong;Chon, Chul-Min;Kim, Dong-Jin
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.4 no.2
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    • pp.101-111
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    • 2016
  • It is possible that aggregates add on to geopolymer based fly ash to mix mortar and concrete like cement. This is necessary to evaluate mineral composition, particle shape, surface, size distribution, density and absorption ratio for fine aggregates due to few detailed research to examine influence of fine aggregates properties on unhardened geopolymer concrete. In this research, used two different fine aggregates, Jumunjin sand(having quartz, mica, feldspar, pyroxene in mineral composition, more than 96% of total size between -0.60 and +0.30mm, angular shape and rough surface) and ISO sand(having almost all quartz in mineral composition, more than 51% size between -1.40 and +0.60mm, simultaneously varied size distribution, spherical shape and smooth surface). After an experimental result of the varied ratio of Si/Al=1.0-4.1 geopolymer paste, mix proportion respectively applied Si/Al=1.5 having the highest compressive strength to mortar and Si/Al=3.5 having the highest consistency to concrete. Geopolymer mortar by mixing with Jumunjin and ISO sand in varied range of 20-50wt.% showed flow size increase between 69.5 and 112.0mm, between 70.5 and 126.0mm respectively. Geopolymer concrete at an addition of 77wt.% of total aggregates ratio showed that average compressive strength was 32MPa and the consistency was favorable to molding. Since ISO sand observing varied size distribution, spherical shape, smooth surface, low absorption ratio resulted in advantageous properties on consistency of geopolymer, geopolymer concrete can be suitable for using the fine aggregates similar to ISO sand.

The Differences in Resting Pulmonary Function in Relation to the Nutritional status of Patients with Chronic Obstructive Pulmonary Disease (만성폐쇄성폐질환 환자의 영양상태에 따른 안정시 폐기능 차이)

  • Mun, Yeung-Chul;Yu, Sung-Keun;Park, Hye-Jung;Park, Jong-Won;Shin, Kyeong-Cheol;Chung, Jin-Hong;Lee, Kwan-Ho;Kim, Jung-Soon
    • Tuberculosis and Respiratory Diseases
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    • v.51 no.6
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    • pp.570-578
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    • 2001
  • Background: With cases of chronic obstructive pulmonary disease(COPD), weight loss and low body weight have been found to correlate with increased mortality and poor prognosis. Therefore, nutritional aspects are an important part of the treatment in cases of COPD. In Korea, there is only limited data available for the changes of resting pulmonary function in relation to nutritional status. This study was carried out to investigate the differences of resting pulmonary function in relation to the nutritional status of patients with COPD. Method : 83 stable patients, with moderate to severe COPD, were clinically assessed for their nutritional status and resting pulmonary function. The patients' nutritional status was evaluated by body weight and fat-free mass (FFM), which was assessed by bioelectrical impedance analysis. According to their nutritional status, the 83 patients were divided into two groups, designated as the depleted, and non-depleted, groups. Result : Of the 83 patients, 31% were characterized by body weight loss and depletion of FFM, whereas 28% had either weight loss or depleted FFM. In the depleted group, significantly lower peak expiratory flow rate(p<0.05) and Kco(p<0.01), but significantly higher airway resistance(Raw, p<0.05) were noted. There was no difference for the non-depleted group in forced expiratory volume at one second, residual volume, inspiratory vital capacity, or total lung capacity. Maximal inspiratory pressure($P_{Imax}$) was also significantly lower in the depleted group(p<0.05). Conclusion : We conclude, from our clinical studies, that nutritional depletion is significantly associated with the change in resting pulmonary function for patients with moderate to severe COPD.

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STUDY OF RAT EPIGASTRIC VESSELS ACCORDING TO THE FREEZING TIME : HISTOLOGIC, HISTOMORPHOMETRIC, IMMUNOHISTOCHEMICAL & SCANNING ELECTRON MICROSCOPIC STUDY (백서 상복부 혈관의 동결시간에 따른 변화에 대한 연구)

  • Kim, Woo-Chan;Lee, Chong-Heon;Kim, Kyung-Wook;Kim, Chang-Jin
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.21 no.2
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    • pp.89-109
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    • 1999
  • Vascular spasm which has been reported to occur in 25% of clinical cases continues to be a problem in microvascular surgery; When prolonged and not corrected, it can lead to low flow, thrombosis, and replant or free flap failure. Ischemia, intimal damage, acidosis and hypovolemia have been implicated as contributors to the vascular spasm. Although much work has been done on the etiology and prevention of vasospasm, a spasmolytic agent capable of firmly protecting against or reversing vasospasm has not been found. Therefore vascular freezing was introduced as a new safe method that immediately and permanently relieves the vasospasm and can be applied to microsurgical transfers. Cryosurgery can be defined as the deliberate destruction of diseased tissue or relief the vascular spasm in microvascular surgery by freezing in a controlled manner. 96 Sprague Dawley rats each weighing within 250g were used and divided into 2 group, experimental 1 and 2 group. In the experimental 1 group, right epigastric vessels (artery and vein) were freezed with a cryoprobe using $N_2O$ gas for 1 min. In the experimental 2 group, after freezing for 1 min, thawing for 30 secs and repeat freezing for 30 secs. Left side was chosen as control group in both group. We sacrified the experimental animals by 1 day, 3 days, 1 week, 2 weeks, 4 weeks & 5 months and observed the sequential change that occur during regeneration of epigastric vessels using a histologic, histomorphometric, immunohistochemical and SEM study after the vascular freezing. The results were as follows1. In epigastric arteries, internal diameters had statistically significant enlargement in 1 day, 3 days of Exp-1 group and 1 day, 3 days, 1 week & 2 weeks of Exp-2 group. Wall thickness had statistically significant thinning in 2 weeks of Exp-2 group. 2. In epigastric veins, internal diameters had enlargement of statistical significance in 1 day of Exp-1 and Exp-2 group. 3. The positive PCNA reactions in smooth muscle appeared in 1 week and increased until 2 weeks, decreased in 4 weeks. There was no statistical significance between Exp-1 and Exp-2 group. 4. The positive ${\alpha}$-SMA reaction in smooth muscles showed weak responses until 1 week and slowly increased in 2 weeks and showed almost control level in 4 weeks. 5. The positive S-100 reactions in the perivascular nerve bundles showed markedly decrease in 1 day, 3 days and increased after 1 week and showed almost control level in 4 weeks. Exp-1 group had stronger response than Exp-2 group. 6. In SEM, we observed defoliation of endothelial cell and flattening of vessel wall. Exp-2 group is more destroyed and healing was slower than Exp-1 group. To sum up, relief of vasospasm (vasodilatation) by freezing with cryoprobe was originated from the damage of smooth muscle layer and perivascular nerve bundle and the enlargement of internal diameter in vessels was similar to expeimental groups, but Exp-2 group had slower healing course and therefore vessel freezing in microsurgery can be clinically used, but repeat freezing time needs to be studied further.

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Plasma-assisted Catalysis for the Abatement of Isopropyl Alcohol over Metal Oxides (금속산화물 촉매상에서 플라즈마를 이용한 IPA 저감)

  • Jo, Jin Oh;Lee, Sang Baek;Jang, Dong Lyong;Park, Jong-Ho;Mok, Young Sun
    • Clean Technology
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    • v.20 no.4
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    • pp.375-382
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    • 2014
  • This work investigated the plasma-catalytic decomposition of isopropyl alcohol (IPA) and the behavior of the byproduct compounds over monolith-supported metal oxide catalysts. Iron oxide ($Fe_2O_3$) or copper oxide (CuO) was loaded on a monolithic porous ${\alpha}-Al_2O_3$ support, which was placed inside the coaxial electrodes of plasma reactor. The IPA decomposition efficiency itself hardly depended on the presence and type of metal oxides because the rate of plasma-induced decomposition was so fast, but the behavior of byproduct formation was largely affected by them. The concentrations of the unwanted byproducts, including acetone, formaldehyde, acetaldehyde, methane, carbon monoxide, etc., were in order of $Fe_2O_3/{\alpha}-Al_2O_3$ < $CuO/{\alpha}-Al_2O_3$ < ${\alpha}-Al_2O_3$ from low to high. Under the condition (flow rate: $1L\;min^{-1}$; IPA concentration: 5,000 ppm; $O_2$ content: 10%; discharge power: 47 W), the selectivity towards $CO_2$ was about 40, 80 and 95% for ${\alpha}-Al_2O_3$, $CuO/{\alpha}-Al_2O_3$ and $Fe_2O_3/{\alpha}-Al_2O_3$, respectively, indicating that $Fe_2O_3/{\alpha}-Al_2O_3$ is the most effective for plasma-catalytic oxidation of IPA. Unlike plasma-alone processes in which tar-like products formed from volatile organic compounds are deposited, the present plasma-catalyst hybrid system did not exhibit such a phenomenon, thus retaining the original catalytic activity.

A Experimental Study on Exclusion Ability of Riprap into Bypass Pipe (저층수 배사관 내 유입된 사석 배출능력에 대한 연구)

  • Jeong, Seok Il;Lee, Seung Oh
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.37 no.1
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    • pp.239-246
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    • 2017
  • There are various transversal structures (small dams or drop structures) in median and small streams in Korea. Most of them are concrete structures and it is so hard to exclude low-level water. Unless drainage valves and/or gates would not be installed near bottom of bed, sediment from upstream should be deposited and also contaminants attached to the sediments would devastatingly threaten the water quality and ecosystem. One of countermeasures for such problem is the bypass pipe installed underneath the transversal structure. However, there is still issued whether it would be workable if the gravels and/or stones would roll into and be not excluded. Therefore, in this study, the conditions to exclude the rip stone which enter into the bypass pipe was reviewed. Based on sediment transport phenomenon, the behavior of stones was investigated with the concepts from the critical shear stress of sediment and d'Alembert principle. As final results, the basis condition (${\tau}_c{^*}$) was derived using the Lagrangian description since the stones are in the moving state, not in the stationary state. From hydraulic experiments the relative velocity could be obtained. In order to minimize the scale effect, the extra wide channel of 5.0 m wide and 1.0 m high was constructed and the experimental stones were fully spherical ones. Experimental results showed that the ratio of flow velocity to spherical particle velocity was measured between 0.5 and 0.7, and this result was substituted into the suggested equation to identify the critical condition wether the stones were excluded. Regimes about the exclusion of stone in bypass pipe were divided into three types according to particle Reynolds number ($Re_p$) and dimensionless critical shear force (${\tau}_c{^*}$) - exclusion section, probabilistic exclusion section, no exclusion section. Results from this study would be useful and essential information for bypass pipe design in transveral structures.

A Study on the Field Data Applicability of Seismic Data Processing using Open-source Software (Madagascar) (오픈-소스 자료처리 기술개발 소프트웨어(Madagascar)를 이용한 탄성파 현장자료 전산처리 적용성 연구)

  • Son, Woohyun;Kim, Byoung-yeop
    • Geophysics and Geophysical Exploration
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    • v.21 no.3
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    • pp.171-182
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    • 2018
  • We performed the seismic field data processing using an open-source software (Madagascar) to verify if it is applicable to processing of field data, which has low signal-to-noise ratio and high uncertainties in velocities. The Madagascar, based on Python, is usually supposed to be better in the development of processing technologies due to its capabilities of multidimensional data analysis and reproducibility. However, this open-source software has not been widely used so far for field data processing because of complicated interfaces and data structure system. To verify the effectiveness of the Madagascar software on field data, we applied it to a typical seismic data processing flow including data loading, geometry build-up, F-K filter, predictive deconvolution, velocity analysis, normal moveout correction, stack, and migration. The field data for the test were acquired in Gunsan Basin, Yellow Sea using a streamer consisting of 480 channels and 4 arrays of air-guns. The results at all processing step are compared with those processed with Landmark's ProMAX (SeisSpace R5000) which is a commercial processing software. Madagascar shows relatively high efficiencies in data IO and management as well as reproducibility. Additionally, it shows quick and exact calculations in some automated procedures such as stacking velocity analysis. There were no remarkable differences in the results after applying the signal enhancement flows of both software. For the deeper part of the substructure image, however, the commercial software shows better results than the open-source software. This is simply because the commercial software has various flows for de-multiple and provides interactive processing environments for delicate processing works compared to Madagascar. Considering that many researchers around the world are developing various data processing algorithms for Madagascar, we can expect that the open-source software such as Madagascar can be widely used for commercial-level processing with the strength of expandability, cost effectiveness and reproducibility.