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The Scale-dependent of Hydraulic Conductivity in Leaky Confined Aquifer with High Permeability at the Ttaan Isle, Gimhae City (김해 딴섬의 고투수성 누수 피압대수층에서 수리전도도의 규모종속효과)

  • Kim, Tae-Yeong;Kang, Dong-Hwan;Kim, Sung-Soo;Kim, Byung-Woo;Kwon, Byung-Hyuk
    • The Journal of Engineering Geology
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    • v.18 no.4
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    • pp.415-422
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    • 2008
  • Pumping test was conducted to understand hydraulic conductivity for leaky confined aquifer with high permeability. Test aquifer was formed in $25{\sim}35\;m$ below ground surface at predetermined site of riverbank filtration which junction of Nakdong river and Milyang river in the Ttaan isle, Gimhae city, Korea Monitoring wells were located at intervals of 2 m and 5 m from pumping well in south-west direction (MW1 and MW2 wells) and northeast direction (MW3 and MW4 wells), respectively. Pumping test was continuously conducted for constant pumping rate of $2,500m^3/day$, hydraulic conductivity was estimated using AQTESOLV 3.5 program. Hydraulic conductivity were estimated to be $1.745{\times}10^{-3}m/sec$ for pumping well (PW), $2.452{\times}10^{-3}m/sec$ for between PW and MW1 wells, $2.161{\times}10^{-3}m/sec$ for between PW and MW2 wells, $2.270{\times}10^{-3}m/sec$ for between PW and MW3 wells and $2.591{\times}10^{-3}m/sec$ for between PW and MW4 wells. The function of hydraulic conductivity (K) as monitoring distance (d) were estimated to be logK = 0.0693logd - 2.671 for south-west direction (PW-MW1-MW2 line), logK = 0.0817logd - 2.655 for north-east direction (PW-MW3-MW 4 line). Scale exponent of hydraulic conductivity as test volume was estimated using Schulze-Makuch et al.(1999) method. Scale exponent of this aquifer was estimated to be 0.15. It means that test aquifer has very low heterogeneity. The radius of influence estimated using transmissivity, maximum groundwater level displacement, distance from pumping well and pumping rate during pumping test were 7.148 m for south-west direction and 6.912 m for north-east direction. The increasing rate of hydraulic conductivity from pumping well to maximum radius of influence were estimated to be 1.40 times for south-west direction and 1.49 times for north-east direction. Thus, heterogeneity of test aquifer was a little higher in north-east direction.

Characteristics of Shear Strength and Elastic Waves in Artificially Frozen Specimens using Triaxial Compression Tests (삼축압축실험을 이용한 인공동결시료의 강도평가 및 탄성파 특성변화)

  • Kim, JongChan;Lee, Jong-Sub;Hong, Seung-Seo;Lee, Changho
    • The Journal of Engineering Geology
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    • v.24 no.1
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    • pp.111-122
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    • 2014
  • For accurate laboratory evaluations of soil deposits, it is essential that the samples are undisturbed. An artificial ground-freezing system is the one of the most effective methods for obtaining undisturbed samples from sand deposits. The objective of this study is to estimate the shear strengths and the characteristics of elastic waves of frozen-thawed and unfrozen specimens through the undrained triaxial compression test. For the experiments, Jumunjin standard sands are used to prepare frozen and unfrozen specimens with similar relative densities (60% and 80%). The water pluviation method is used to simulate the fully saturated condition under the groundwater table. When thawing the frozen specimens, the temperature is measured every minute. After the specimens are completely thawed, undrained triaxial compression tests are conducted using the same procedures as for the unfrozen specimens. During the triaxial tests (saturation, consolidation, and shear phase), compressional and shear waves are measured. The results show that the freeze-thaw process has minor effects on the peak deviatoric stress and shear strength values, and that the process does not affect the internal friction angle. The compressional wave velocity increases with increasing B-value to 1800 m/s in the saturation phase, but tends to remain constant in the process of consolidation and shearing. The shear wave velocity decreases with increasing B-value in the process of saturation, but changes velocity in accordance with the change in effective stress in the processes of consolidation and shearing. The compressional wave velocity has similar values regardless of the freeze-thaw process, but values of shear wave velocity are slighly lower in frozen-thawed specimens than in unfrozen specimens. This study is a preliminary experiment for estimating the shear strength and characteristics of elastic wave velocity in undisturbed frozen specimens that have been obtained using the artificial ground-freezing method.

A Study on the Optimal Operating Conditions for Removal of Nutrient Influential Substances Using Functional Media (기능성 여재를 활용한 부영양화 영양물질 제거의 최적 운전조건 연구)

  • Lee, Jong-Jun;Oh, Jong-Min;Choi, Seung-Jong;Kim, Ki-Jung
    • Journal of Environmental Impact Assessment
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    • v.28 no.6
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    • pp.549-555
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    • 2019
  • The purpose of this study is to ensure optimal operating conditions for improving the removal efficiency of phosphorus (P) and nitrogen (N) that are the causative agents of eutrophication by utilizing functional media. The main ingredients of the functional media used in this study are Si, Al, and Fe, SiO2, KAlSiO3O8, Al2O2·2SiO2O, H3Al2Si2O9, Fe3O4O), and berylite. To identify the maximum efficiency of the filtration process, the processing efficiency experiment was carried out according to flow method, velocity, and thickness of residual media. The flow method carried out two experiments, 50 m/day, 100 m/day, 150 m/day, 200 m/day, 250 m/day, and 20 cm, 40 cm, 50 cm, 60 cm, 80 cm of lead depth. Experiments have shown that SS, T-N, and T-P all showed higher elimination efficiency of the upflow current conditions than the downflow current conditions, and that the processing efficiency of the linearity is the highest at SS 50 m/day, T-N 150 m/day and T-P 100 m/day. In addition, the analysis of the removal efficiency according to the residual thickness showed that SS, T-N, and T-P all showed the highest efficiency at 60 cm. In addition, the analysis of the removal efficiency according to the residual thickness showed that SS, T-N, and T-P all showed the highest efficiency at 60 cm. It is considered desirable to set the top-down flow conditions and residual thickness of 60 cm and adjust the velocity of the line according to the target media for removal.

Growth and Opto-electric Characterization of ZnSe Thin Film by Chemical Bath Deposition (CBD(Chemical Bath Deposition)방법에 의한 ZnSe 박막성장과 광전기적 특성)

  • Hong, K.J.;You, S.H.
    • Journal of Sensor Science and Technology
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    • v.10 no.1
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    • pp.62-70
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    • 2001
  • The ZnSe sample grown by chemical bath deposition (CBD) method were annealed in Ar gas at $45^{\circ}C$. Using extrapolation method of X-ray diffraction pattern, it was found to have zinc blend structure whose lattice parameter $a_o$ was $5.6687\;{\AA}$. From Hall effect, the mobility was likely to be decreased by impurity scattering at temperature range from 10 K to 150 K and by lattice scattering at temperature range from 150 K to 293 K. The band gap given by the transmission edge changed from $2.700{\underline{5}}\;eV$ at 293 K to $2.873{\underline{9}}\;eV$ at 10 K. Comparing photocurrent peak position with transmission edge, we could find that photocurrent peaks due to excition electrons from valence band, ${\Gamma}_8$ and ${\Gamma}_7$ and to conduction band ${\Gamma}_6$ were observed at photocurrent spectrum. From the photocurrent spectra by illumination of polarized light on the ZnSe thin film, we have found that values of spin orbit coupling splitting ${\Delta}so$ is $0.098{\underline{1}}\;eV$. From the PL spectra at 10K, the peaks corresponding to free bound excitons and D-A pair and a broad emission band due to SA is identified. The binding energy of the free excitons are determined to be $0.061{\underline{2}}\;eV$ and the dissipation energy of the donor -bound exciton and acceptor-bound exciton to be $0.017{\underline{2}}\;eV$, $0.031{\underline{0}}\;eV$, respectively.

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Fine Structural Changes of the Renal Corpuscle of the Mice following the Administration of 5-Fluorouracil or Mitomycin C (5-Fluorouracil 및 Mitomycin C 투여후 생쥐 콩팥소체의 미세구조 변화)

  • Ko, Jeong-Sik;Oh, Won-Young;Kim, Jin-Gook;Park, Kyung-Ho;Ahn, E-Tay
    • Applied Microscopy
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    • v.29 no.1
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    • pp.25-41
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    • 1999
  • The experiment was performed to study the morphological responses of the renal glomeruli of the mice after administration of 5-fluorouracil or mitomycin C. 5-fluorouracil (60 mg/kg) or mitomycin-C $(400{\mu}g/kg)$ were injected subcutaneously to the animals every other day, and animals were sacrificed at 4 days or 7 days following the first injections. Pieces of tissues were observed with a JEM 100CX-II electron microscope. The observed results were as follows: 1. In the fourth day following the first injection of 5-fluorouracil or mitomycin C, components of the renal glomeruli of the mice are looked compact since they were filled with the widened the mesangium, and showed narrowing lumen of glomerular capillaries and of urinary spaces. The changes were more significant in the mitomycin C treated mice. 2. In the 5-fluorouracil treated mice, morphological changes of glomeruli were generally recovered in the seventh day, whereas the glomeruli of the mitomycin C treated mice have not shown general recovery. 3. In the fourth and seventh days following the first injection of mitomycin C, in the renal glomeruli of the mice, swollen endothelial cells, and protruded mesangeal cells into the capillary lumen are frequently observed. 4. In the fourth day following the first injection of mitomycin C, in the glomerular basal lamina of the mice, the electron densities of the lamina rara interna and the lamina rara externa were similar to the density of the lamina densa and the expanded lamina rara interna were often seen. From the above results, it is suggested that the cytotoxic effects of the mitomycin C on renal glomeruli are more severe as compared with those of 5-fluorouracil.

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Structural Features of Various Trichomes in Vitex negundo during Development (방향성 좀목형(Vitex negundo)모용의 구조적 분화발달)

  • Lee, Seung-Hee;Kim, In-Sun
    • Applied Microscopy
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    • v.36 no.1
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    • pp.35-45
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    • 2006
  • Plants of Vitex negundo are known to develop numerous trichomes throughout their body, where certain trichome types have been believed to be one of the plausible structures for the unique scents. In the current study. structural aspects of the trichomes have been examined in leaves and stems of Vitex negundo using TEM and SEM. Trichome types as well as structural changes that occurred in certain trichomes during secretion have been mainly focused. Three type of glandular trichomes and two types of non-glandular trichomes were developed in the epidermis of young and mature Vitex negundo plants. The glandular trichomes included the peltate type (Type 1), the capitate type (Type 2), and degraded capitate type (Type 3), whereas the non-glandular warty trichomes contained the multicellular (Types 4) and unicellular type (Type 5). Type 1 and 2 consisted of head and stalk cells, but their number and size were different. One secretory cavity was formed from the four head cells in the former, but only two head cells were involved in the latter. The cytoplasmic density in the head cell was quite high and in particular, sER and Golgi bodies were well developed. At initiation of their development, the cuticle layer of the head cells separated from the outer tangential wall to form a secretory cavity. Subsequently the cavity expanded acropetally and a large number of secretory vesicles continuously produced from the head cells until they filled the entire cavity. The cavity contained materials that would be soon discharged into intercellular spaces and/or into the air. The cavity began to decrease the volume by contracting at initial secretion but degrade rapidly within short time. It has been suggested that the mode of secretion in V. negundo is probably the eccrine secretion, since no break or rupture of the cavity has been observed during examination. Contrastingly Type 3 exhibited deterioration of the head cell at early stage. Type 4 was about $110{\sim}190{\mu}m$ long, consisting of $2{\sim}3$ cells, and distributed more in the adaxial epidermis compared to the abaxial surface. However, $20{\sim}30{\mu}m$ long Type 5 was extremely dense in both epidermis. Among several trichome types, Type 1 and 2 probably play an important role in discharging unique aromatic scents in plants of V. negundo.

Expression of Growth Factors and Secretory Leukocyte Protease Inhibitor (SLPI) in RAW264.7 Cells after Lipopolysaccharide (LPS) Stimulation (대식세포주 (RAW264.7)에서 박테리아성 지질다당류 (LPS) 자극에 의한 분비백혈구단백분해효소억제제 (SLPI)와 성장인자들의 발현)

  • Son, Wook-Hee;Choi, Baik-Dong;Jeong, Soon-Jeong;Wang, Guan-Lin;Hwang, Ho-Keel;Jeong, Moon-Jin
    • Applied Microscopy
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    • v.37 no.2
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    • pp.93-102
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    • 2007
  • Secretory leukocyte protease inhibitor (SLPI) was known as one of bacterial lipopolysaccharide (LPS)-induced products of macrophage. Macrophages play an important role in the development of inflammatory responses by secreting an array of cytokines and chemokines in a tissue microenvironment. To identify the function and relationship between potent growth factors and SLPI after LPS stimulation, we conducted reverse transcriptase polymerase chain reaction (RT-PCR) and Western blots for the detection of mRNA and protein expression of SLPI and growth factors such as VEGF, PDGF, bFGF after 100 ng LPS stimulation on the RAW264.7 cells. The result of RT-PCR was showed SLPI mRNA expression was increased from 60 min to 48h in RAW 264.7 cells after incubation with LPS. VEGF and PDGF mRNA was expressed highly at initial stage by LPS stimulation. The mRNA of bFGF and type I collagen was very weakly expressed after LPS stimulation. SLPI protein level was increased likely the mRNA levels in RAW 267.7 cells. Additionally, phase contrast and scanning electron microscopic observation demonstrated that the LPS induce the change of morphology of the RAW264.7 cells. From these results, it suggest that expression of SLPI by LPS treatment may associate with VEGF and PDGF expression in RAW264.7 cells.

A Study on the Manual Skills of Experimental Apparatuses of Preservice Elementary School Teachers (초등 예비교사의 실험 기구 조작 능력에 대한 연구)

  • Lee, So-Ree;Choi, Hyun-Dong;Lim, Jae-Keun;Shin, Se-Young;Yang, Il-Ho
    • Journal of Science Education
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    • v.35 no.1
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    • pp.80-90
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    • 2011
  • The purpose of this study is to investigate manual skills of experimental apparatuses of pre-service elementary school teachers by examining and analyzing the process of experiments conducted by pre-teachers. For this study, 24 pre-service elementary school teachers were selected as the subjects and 4 experimental apparatuses were chosen through analyzing science textbooks from 3rd grade to 6th grade in elementary school. The selected experimental apparatuses were alcohol burner, dropper, microscope, instruments for making a prepared specimen. In addition, a task was carefully chosen to conduct an investigation in real settings and a series of evaluation standards was developed. While 3 subjects conducted experiments in separated and independent space at the same time, 3 collaborators observed the experiment process and recorded whether the subject met the evaluation standards or not, using O, X. The study suggests that pre-service elementary school teachers' manual skills of experimental apparatuses were under far below our projections. Particularly, in case of alcohol burner, the subjects showed lower ability to properly light the burners - which is to brush through the lampwick with fire - and to adjust the height of tripods according to the flame. Also, when it comes to dropper, they were not held the way they were supposed to be. In addition, when designing prepared specimen, the subjects used their hands instead of tweezers and often skipped the process of dripping water drop and wiping water with an oilpaper. Moreover, they did not know how to use a microscope properly so there were many times that they could not focus a microscope, failing to observe the objects. Educational implications are discussed.

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Fashion Color Planning Using Dyeing with Jeju Natural Resources (제주 천연자원의 염색을 활용한 패션 색채기획)

  • Ahn, Su-min;Sarmandakh, Badmaanyambuu;Yi, Eunjou
    • Science of Emotion and Sensibility
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    • v.19 no.2
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    • pp.55-66
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    • 2016
  • This study was aimed to characterize the color of cotton fabric dyed with three different natural resources such as persimmon, citrus, and brown algae and to propose new trend color themes for fashion color planning for newborn and toddler wear. A variety of color shades by dyeing cotton fabric with persimmon, citrus, and brown algae respectively was obtained and each color was also determined if it could be matched with one of Pantone TPX considering authorized color trends for 2016 Spring/Summer. Finally a group of new trend color theme for 2016S/S newborn and toddler wear were proposed for naturally dyed cotton fabric. As results, the three natural dyeing resources gave color gamut with hue ranging from Purple Blue to Green Yellow and with tones including pale, light grayish, soft, grayish, and dull by their single and compound dyeing. A total of 23 colors matched to Pantone TPX were considered for the fashion color planning by natural dyeing. The selected natural colors were grouped as three different color ways and thereafter the color ways were differentiated in terms of representative color sensibility by using subjective evaluation. Finally three characterized color themes were proposed as 'Serenity', 'Juicy', and 'Fancy', each of which has tried to express differentiated feeling of each natural resources for dyeing, to follow up to global color trends, and to contribute to newborn and toddler wear's own requirements and marketability. These results suggest that natural dyeing colors could be applied into fashion color planning in current fashion industries in order to produce more sensible and emotional design of fashion goods using natural dyeing.

Comparison of Results Between Immediate Fixation Group and Delayed Reconstruction Group in Displaced Mid-shaft Fractures of the Clavicle (쇄골 전위성 간부 골절에서 조기 고정술 군과 지연 재건술 군 간의 결과 비교)

  • Kim, Doo-Sub;Rah, Jung-Ho;Yoon, Yeo-Seung;Lee, Chang-Ho
    • Clinics in Shoulder and Elbow
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    • v.12 no.1
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    • pp.61-66
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    • 2009
  • Purpose: Several authors have reported excellent results of delayed reconstruction of non-union & malunion in displaced mid-shaft fractures of the clavicle and these results were equal to that of immediate fixation. But direct comparison between these treatments is rare. We evaluated the results between the immediate fixation group and delayed reconstruction group for treating displaced mid-shaft fractures of the clavicle. Materials and Methods: We studied the results of 18 cases with immediate fixation of displaced mid-shaft fractures of the clavicle and 15 cases with delayed reconstruction of non-union & malunion after conservative management, and these cases were seen from March 2000 to February, 2006. The final postoperative outcome was analyzed according to the clinical outcomes with using the Constant score and the radiological findings of bony union. Results: The constant score was low in the delayed reconstruction group compare to that of the immediate fixation group (p value=0.045). For the pain score & the activities of daily living score, a statistically significant difference was seen between the two groups (p<0.05), but not for the range of motion score & the power score (p>0.05). Radiological findings of bony union were seen for both groups at an average of 8.8 weeks for the immediate fixation group and at an average of 9.8 weeks for the delayed reconstruction group. Conclusion: Though the delayed reconstruction group was shown good clinical and radiological results, the immediate fixation group had a significantly better pain score, a better activities of daily living score and a better Constant score. It is important to choose the initial treatment option for displaced mid-shaft fractures of the clavicle after sufficient explanation to patients about the merits and demerits between these two treatment options.