• 대한토목학회논문집
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• 제36권2호
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• pp.219-229
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• 2016

본 연구에서는 저수지의 붕괴로 인한 하류부 하천의 하상변동에 대한 해석을 수행하였다. 저수지 붕괴에 따른 1차원 비평형, 비균일 유사의 이송과 하상 변동을 연구를 위해 CCHE1D 모형을 이용하였다. CCHE1D 모형은 비평형 및 비균일 유사해석을 위해 조정거리와 분류된 입자의 입경을 사용하며, 하상 물질의 교환을 위한 혼합층의 개념이 사용된다. CCHE1D 모형을 1996년 저수지 붕괴가 발생한 Ha!Ha!강 유역에 적용하여 저수지 붕괴로 인한 하류부의 비평형, 비균일 유사이송을 해석하고, 계산 결과를 저수지 붕괴전 후에 하류부 실측 하상과 비교하였다. 또한, 조정계수($L_{s,b}$), 비평형 계수(${\alpha}_s$), 혼합층 두께(${\delta}_m$), 공극률(p')을 포함하는 주요 매개변수에 대한 민감도를 분석하였으며, 대상유역에서는 비평형 계수가 하상변동에 가장 큰 영향을 주는 것으로 나타났다.

• 동의생리병리학회지
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• 제25권3호
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• pp.482-488
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• 2011

Cadmium (Cd) is well known as a spermatotoxic and gonadotoxic heavy metal ion. This study was performed to assess the possible protective effect of Enerbalance on Cd-induced spermiotoxicity and testicular damage. The control group received isotonic saline; Cd group received Cd (2 mg/kg BW per day) orally; extract-treated groups were orally administrated with Enerbalance (50 mg and 100 mg/kg BW per day) and Cd for 10 days. Morphological changes of testicular tissue, sperm characteristics, oxidative/antioxidative parameters from testis, and serum sexual hormone level were determined. Enerbalance was significantely increased sperm amount in cauda epididymis without changes of ratio of epididymis/body weight and testis/body weight. Cd caused a marked decrease in epididymal sperm concentration and chemotactic sperm motility, testicular superoxide dismutase (SOD), catalase (CAT), Enerbalance was significantly ameliorated loss of epididymal sperm concentration, sperm chemotactic motility, antioxidative parameters, and male hormone whereas decreased abnormal architecture by testis damage. Enerbalance was successfully attenuated these adverse effects of Cd and offers a dose-dependent protection. Our study demonstrated that Enerbalance could proffer a measure of protection against Cd-induced testicular damage and spermiotoxicity by possibly reducing oxidative stress and increasing the antioxidant defense mechanism in mice.

• 한국정밀공학회지
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• 제26권10호
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• pp.122-128
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• 2009

The aim of this study was to investigate, through a longitudinal tracking, whether gender influences morphological characteristics on trabeucular bone of tibia during unloading. 12 male and 15 female ICR mice at 6 week of age were used and randomly allocated into two groups in each gender; unloading and normal group, respectively Mice in unloading group were operated on denervation (sciatic neurectomy). The tibiae were scanned by using in vivo micro-computed tomography (micro-CT) at 0 day (before denervation) and after 14 days. Structural parameters and BMD on tibia were measured. In female, BV/TV (65%), Tb. Th (5%), Tb.N (61%) and BMD (62%) were significantly decreased and BS/BV (17%), Tb.Sp (54%), SMI (19%) and Tb.Pf (75%) were significantly increased after unloading (p<0.05). In male, BV/TV (1%) and Tb.N (10%) were significantly decreased and SMI (5%) was significantly increased after unloading (p<0.05). In addition, trabeuclar bone loss of female was significantly bigger than that of male (p<0.05). These results indicated that effects of unloading on trabecular bone in growing mice might have difference between female and male, although unloading result in loss of quantity and quality on trabecular bone both female and male.

• Journal of Astronomy and Space Sciences
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• 제34권4호
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• pp.315-330
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• 2017

Halo coronal mass ejections (CMEs) originating from solar activities give rise to geomagnetic storms when they reach the Earth. Variations in the geomagnetic field during a geomagnetic storm can damage satellites, communication systems, electrical power grids, and power systems, and induce currents. Therefore, automated techniques for detecting and analyzing halo CMEs have been eliciting increasing attention for the monitoring and prediction of the space weather environment. In this study, we developed an algorithm to sense and detect halo CMEs using large angle and spectrometric coronagraph (LASCO) C3 coronagraph images from the solar and heliospheric observatory (SOHO) satellite. In addition, we developed an image processing technique to derive the morphological and dynamical characteristics of halo CMEs, namely, the source location, width, actual CME speed, and arrival time at a 21.5 solar radius. The proposed halo CME automatic analysis model was validated using a model of the past three halo CME events. As a result, a solar event that occurred at 03:38 UT on Mar. 23, 2014 was predicted to arrive at Earth at 23:00 UT on Mar. 25, whereas the actual arrival time was at 04:30 UT on Mar. 26, which is a difference of 5 hr and 30 min. In addition, a solar event that occurred at 12:55 UT on Apr. 18, 2014 was estimated to arrive at Earth at 16:00 UT on Apr. 20, which is 4 hr ahead of the actual arrival time of 20:00 UT on the same day. However, the estimation error was reduced significantly compared to the ENLIL model. As a further study, the model will be applied to many more events for validation and testing, and after such tests are completed, on-line service will be provided at the Korean Space Weather Center to detect halo CMEs and derive the model parameters.

• 대한금속재료학회지
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• 제50권2호
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• pp.107-115
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• 2012

Direct laser melting (DLM) is a powder-based additive manufacturing process to produce parts by layer-by-layer laser melting. As the properties of the manufactured parts depend strongly on the deposited laser-melted bead, deposited layers obtained by the DLM process were characterized in this study. This investigation used a 200 W fiber laser to produce single-line beads under a variety of different energy distributions. In order to obtain a feasible range for the two main process parameters (i.e. laser power and scan rate), bead shapes of single track deposition were intensively investigated. The effects of the processing parameters, such as powder layer thickness and scan spacing, on geometries of the deposited layers have also been analyzed. As a result, minimum energy criteria that can achieve a complete melting have been suggested at the given powder layer thickness. The surface roughnesses of the deposited beads were strongly dependent on the overlap ratio of adjacent beads and on the energy distributions of laser power. Through microstructural analysis and hardness measurement, the morphological and mechanical properties of the deposited layers at various overlapped beads have also been characterized.

• 식품보건융합연구
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• 제5권3호
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• pp.1-5
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• 2019

The field experiment was conducted in vegetable area, Institute of Horticultural Sciences in University of Agriculture, Faisalabad in order to recognize morphological and fruit growth pattern and yield of Tinda (Praecitrullus fistulosus) gourd germplasm lines. Sixteen germplasm lines in which one line is used as check are included were sown and grown on flat beds in field. The field experiment was arranged as randomized complete block design (RCBD) with three replications. Data on days to maturity, fruit per vine, fruit weight in grams, fruit diameter and total yield obtained were recorded. The fruit texture is marked as phenotype parameter. All parameters were collected and then analyzed statistically. All lines and replications showed different results among each other according to parameter. The maximum DTM (days to maturity), F/P (fruit per plant), FW (fruit weight), FD (fruit diameter) and Yield were recorded was $L_0$ (68.66), $L_3$ (1.66), $L_{10}$ (248.33), $L_{13}$ (8.50) and $L_0$ (599.33) and the minimum were recorded was $L_1$ (56), $L_{11}$ (0.33), $L_0$ (198), $L_9$ (7) and $L_4$ (421) grams respectively. All lines showed smooth texture of fruits with no hairs when mature at harvesting stage.

• Fisheries and Aquatic Sciences
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• 제22권4호
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• pp.8.1-8.9
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• 2019

A 12-week feeding trial was designed to evaluate the effect of total replacement of fish oil (FO) with terrestrial alternative oils on growth, feed utilization, body composition, hematological parameters, and fillet fatty acid profile of mandarin fish juveniles. Four iso-nitrogenous (56% crude protein) and iso-lipidic (13% crude lipid) practical diets were formulated. A control diet contained 6% FO and three other experimental diets were prepared by replacing FO with linseed oil, soybean oil, and lard (designed as FO, LO, SO, and lard, respectively). Each diet was randomly allocated to triplicate groups of 25 fish ($1.8{\pm}0.03g/fish$) in a circular tank. Complete replacement of FO by three tested alternative oils had no remarkable impact on growth performance, feed utilization efficiency, and morphological and hematological parameters of juvenile mandarin fish. However, daily feed intake was found to be significantly higher for fish fed the SO diet compared with those fed the FO and LO diets. Fish fed LO and SO diets exhibited significantly higher levels of the whole body lipid compared to fish fed diet containing FO. Fillet fatty acid composition reflected dietary fatty acid profile. The highest level of ${\alpha}$-linolenic acid, linoleic acid, and oleic acid was observed in fish fillet fed LO, SO, and lard, respectively. Although the eicosapentaenoic acid level of fish fillet fed diet FO was higher than other treatments, no significant difference was found in docosahexaenoic acid content among all dietary groups. The results of the present study clearly demonstrate that the complete replacement of FO in mandarin fish diets is achievable. These findings are useful in dietary formulation to reduce feed costs without compromising mandarin fish growth.

• Investigative Magnetic Resonance Imaging
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• 제25권1호
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• pp.23-34
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• 2021

Purpose: Differentiating between glioblastoma and solitary metastasis is very important for the planning of further workup and treatment. We assessed the ability of various morphological parameters using conventional MRI and diffusion-based techniques to distinguish between glioblastomas and solitary metastases in tumoral and peritumoral regions. Materials and Methods: We included 38 patients with solitary brain tumors (21 glioblastomas, 17 solitary metastases). To find out if there were differences in the morphologic parameters of enhancing tumors, we analyzed their shape, margins, and enhancement patterns on postcontrast T1-weighted images. During analyses of peritumoral regions, we assessed the extent of peritumoral non-enhancing lesion on T2- and postcontrast T1-weighted images. We also aimed to detect peritumoral neoplastic cell infiltration by visual assessment of T2-weighted and diffusion-based images, including DWI, ADC maps, and exponential DWI, and evaluated which sequence depicted peritumoral neoplastic cell infiltration most clearly. Results: The shapes, margins, and enhancement patterns of tumors all significantly differentiated glioblastomas from metastases. Glioblastomas had an irregular shape, ill-defined margins, and a heterogeneous enhancement pattern; on the other hand, metastases had an ovoid or round shape, well-defined margins, and homogeneous enhancement. Metastases had significantly more extensive peritumoral T2 high signal intensity than glioblastomas had. In visual assessment of peritumoral neoplastic cell infiltration using T2-weighted and diffusion-based images, all sequences differed significantly between the two groups. Exponential DWI had the highest sensitivity for the diagnosis of both glioblastoma (100%) and metastasis (70.6%). A combination of exponential DWI and ADC maps was optimal for the depiction of peritumoral neoplastic cell infiltration in glioblastoma. Conclusion: In the differentiation of glioblastoma from solitary metastatic lesions, visual morphologic assessment of tumoral and peritumoral regions using conventional MRI and diffusion-based techniques can also offer diagnostic information.

• Journal of Forest and Environmental Science
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• 제38권1호
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• pp.38-47
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• 2022

Hymenodictyon orixensis (Roxb.) Mabberley (locally known as Bhutum in Bangladesh) is both an ecologically and economically valuable multipurpose tree species for afforestation and reforestation programs in Bangladesh. Seed germination and seedling development study of H. orixense were conducted to find out the response to different growing medium, e.g., polybag (15×10 cm (T₀) and 20×15 cm (T₁)), sand medium in propagator house (T₂), conventional nursery bed (T₃), and root trainer (T₄) in the Nursery. Consequently, germination behavior and seedling morphological parameters of H. orixense were assessed. The results revealed that the sand medium of the propagator house (T₂) provided the highest germination % (58.57±22.30) and the highest germination energy (11.43±2.43) followed by seedlings growing in 20×15 cm polybags (T1) containing forest topsoil and cow-dung at a ratio of 3:1. Except for germination energy, germination values, and germination capacity, other seed biology parameters, particularly imbibition, germination period, germination rate, and plant survival percent in T₁, T₂, T₃, and T₄ were significantly (p<0.05) different from T₀. Each phenotypic parameter of seedlings and dry matter of shoot and root significantly differed from control except root length (p<0.992). Based on this study, Polybags of 20×15 cm size are regarded as the best medium for quality seedling development of H. orixense. The nursery bed (T₃) had the lowest germination performance and developed more inferior quality seedlings. Thereby, 20×15 cm size of polybags with conventional soil and cow-dung media is recommended for maximum germination and to grow the quality seedlings of H. orixense in the Nursery.

• 한국미생물·생명공학회지
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• 제43권3호
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• pp.249-258
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• 2015

In this paper, the autolysis process of Saccharomyces cerevisiae FX-2 (S. cerevisiae FX-2) via, a variety of endogenous enzyme, was investigated systematically by analyzing changes in physicochemical parameters in autolysate, surface morphology and the internal structure of the yeast cells. As an explicit conclusion, the arisen autolysis depended on the pH and the optimal pH was found to be 5.5. Based on the experimental data and the characteristics of mycelia morphology, a hypothesis is put forward that simple proteins in yeast vacuolar are firstly degraded for utilization, and then more membrane-bound proteins are hydrolyzed to release hydrolytic enzymes, which arouse an enzymatic reaction to induce the collapse of the cell wall into the cytoplasm.