• Title/Summary/Keyword: Cell size model

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A Study on the Establishment of the Hydro-Parameter by Using GIS - in Tamjin River Basin - (GIS를 이용한 수문매개변수 설정에 관한 연구 - 탐진강 유역을 중심으로 -)

  • Hwang, Eui-Jin;Kim, Woo-Hyeok;Kim, Young-Gyun
    • Journal of Korean Society for Geospatial Information Science
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    • v.11 no.1 s.24
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    • pp.3-12
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    • 2003
  • The main objective of this study is to extract the hydro-Parameter of the Tamjin River basin. A CIS is capable of extracting various hydrological factors from DEM. One of important tasks for hydrological analysis is the division of watershed. In this study, watershed itself and other geometric factors of watershed are extracted from DEM by using a CIS technique. The data of topographical map with scale of 1:25,000 and 1:250,000 in the Tamjin River basin is used for this study and it is converted to DEM date. Various forms of representation of spatial data are handled in main modules and a CRID module of ArcView. A GRID module is used on a stream in order to define watershed boundary. Based on the spatial analysis using those GIS technique, it would be possible to obtain the reasonable results of watershed characteristics. Also, the results show not only that GIS can aid watershed management, research and surveillance, but also that the geometric characteristics as parameters of watershed can be quantified more accurately and easily than conventional graphic methods. From the equations($Y=14632.87{\cdot}X^{-0.542444},\;Y=37014.1{\cdot}X^{-1.058808}$), it can be concluded that the optimal count of flow accumulation is 468 and cell size is 42m for spatial analysis by using GIS technique in Tamjin River basin.

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CFD Modeling for 300MW Shell-Type One-Stage Entrained Flow Coal Gasifier : Effect of $O_2$/Steam/Coal Ratios, Coal Particle Sizes, and Inlet Angles on the Gasifier Performance (300MW급 Shell형 1단 분류층 석탄 가스화기의 전산수치해석 : 산소/스팀/석탄 주입비, 석탄입자 크기, 주입 노즐 각도가 가스화기 성능에 미치는 영향)

  • Song, Ji-Hoon;Kang, Min-Woong;Seo, Dong-Kyun;Lim, Sung-Jin;Paek, Min-Su;Hwang, Jung-Ho
    • Journal of Hydrogen and New Energy
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    • v.21 no.3
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    • pp.227-240
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    • 2010
  • Coal gasification is heading for a great future as one of the cleanest energy sources, which can produce not only electricity and heat, but also gaseous and liquid fuels from the synthesis. The work focuses on 300MW shell type one-stage entrained flow coal gasifier which is used in the Integrated coal Gasification Combined Cycle(IGCC) plant as a reactor. As constructing an IGCC plant is considerably complicated and expensive compared with a pulverized-coal power plant, it is important to determine optimum design factors and operating conditions using a computational fluid dynamics (CFD) model. In this study, the results of numerical calculations show that $O_2$/Coal ratio, 0.83, Steam/Coal ratio, 0.05, coal particle diameter, $100{\mu}m$, injection angle, $4^{\circ}$ (clockwise) are the most optimum in this research.

Effect of pile group geometry on bearing capacity of piled raft foundations

  • Fattah, Mohammed Y.;Yousif, Mustafa A.;Al-Tameemi, Sarmad M.K.
    • Structural Engineering and Mechanics
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    • v.54 no.5
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    • pp.829-853
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    • 2015
  • This is an experimental study to investigate the behaviour of piled raft system in different types of sandy soil. A small scale "prototype" model was tested in a sand box with load applied to the foundation through a compression jack and measured by means of load cell. The settlement was measured at the raft by means of dial gauges, three strain gauges were attached on piles to measure the strains and calculate the load carried by each pile in the group. Nine configurations of group ($1{\times}2$, $1{\times}3$, $1{\times}4$, $2{\times}2$, $2{\times}3$, $2{\times}4$, $3{\times}3$, $3{\times}4$ and $4{\times}4$) were tested in the laboratory as a free standing pile group (the raft not in contact with the soil) and as a piled raft (the raft in contact with the soil), in addition to tests for raft (unpiled) with different sizes. It is found that when the number of piles within the group is small (less than 4), there is no evident contribution of the raft to the load carrying capacity. The failure load for a piled raft consisting of 9 piles is approximately 100% greater than free standing pile group containing the same number of piles. This difference increases to about 4 times for 16 pile group. The piles work as settlement reducers effectively when the number of piles is greater than 6 than when the number of piles is less than 6. The settlement can be increased by about 8 times in ($1{\times}2$) free standing pile group compared to the piled raft of the same size. The effect of piled raft in reducing the settlement vanishes when the number of piles exceeds 6.

Synchronous Buck Converter with High Efficiency and Low Ripple Voltage for Mobile Applications (고 효율 저 리플 전압 특성을 갖는 모바일용 동기 형 벅 컨버터)

  • Yim, Chang-Jong;Kim, Jun-Sik;Park, Shi-Hong
    • Journal of IKEEE
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    • v.15 no.4
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    • pp.319-323
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    • 2011
  • In this paper presents a new model of dual-mode synchronous buck converter with dynamic control for mobile applications was proposed. The proposed circuit can operate at 2.5MHz with supply voltage 2.5V to 5V for low ripple and minimum inductor and capacitor size, which is suitable for single-cell lithium-ion battery supply mobile applications. For high efficiency, the proposed circuit adopts synchronous type and dynamic control. The proposed circuit is designed by using the device parameter of TSMC 0.18um BCD process and the performance is evaluated by Cadence spectre. Experimental board level results show the maximum conversion efficiency is 96% at 100mA load current.

Beneficial Effect of Rubus Coreanus Miq in a Rat Model of High Fructose Diet-induced Metabolic Syndrome (고과당식이 랫드모델에서 복분자 투여에 의한 대사증후군 개선효과)

  • Kho, Min Chul;Lee, Yun Jung;Yoon, Jung Joo;Kang, Dae Gill;Lee, Ho Sub
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.29 no.1
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    • pp.11-17
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    • 2015
  • Overconsumption of fructose results in dyslipidemia, hypertension, which have documented as a risk of cardiovascular diseases. This experimental study was designed to investigate the beneficial effects of Rubus coreanus Miq.(RCM) in high-fructose diet-induced metabolic syndrome. Animals were divided into three groups; Control group fed regular diet and tap water, fructose groups were fed the 65% high-fructose (HF) diet with/without RCM 100 mg/kg/day for 8 weeks, respectively. Chronic treatment with RCM significantly decreased body weight, fat weight and adipocyte size. Moreover, RCM significantly prevented the development of the metabolic disturbances such as hyperlipidemia and hypertension. RCM also led to increase in high density lipoprotein level in the HF group. In addition, RCM suppressed vascular cell adhesion molecule-1 (VCAM-1) expression and significantly recovered the levels of endothelial nitric oxide synthase (eNOS) expression in aorta. These results demonstrates that RCM may be a beneficial therapeutic for metabolic syndrome through the improvement of hyperlipidemia, obesity, and hypertension.

A New True Ortho-photo Generation Algorithm for High Resolution Satellite Imagery

  • Bang, Ki-In;Kim, Chang-Jae
    • Korean Journal of Remote Sensing
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    • v.26 no.3
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    • pp.347-359
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    • 2010
  • Ortho-photos provide valuable spatial and spectral information for various Geographic Information System (GIS) and mapping applications. The absence of relief displacement and the uniform scale in ortho-photos enable interested users to measure distances, compute areas, derive geographic locations, and quantify changes. Differential rectification has traditionally been used for ortho-photo generation. However, differential rectification produces serious problems (in the form of ghost images) when dealing with large scale imagery over urban areas. To avoid these artifacts, true ortho-photo generation techniques have been devised to remove ghost images through visibility analysis and occlusion detection. So far, the Z-buffer method has been one of the most popular methods for true ortho-photo generation. However, it is quite sensitive to the relationship between the cell size of the Digital Surface Model (DSM) and the Ground Sampling Distance (GSD) of the imaging sensor. Another critical issue of true ortho-photo generation using high resolution satellite imagery is the scan line search. In other words, the perspective center corresponding to each ground point should be identified since we are dealing with a line camera. This paper introduces alternative methodology for true ortho-photo generation that circumvents the drawbacks of the Z-buffer technique and the existing scan line search methods. The experiments using real data are carried out while comparing the performance of the proposed and the existing methods through qualitative and quantitative evaluations and computational efficiency. The experimental analysis proved that the proposed method provided the best success ratio of the occlusion detection and had reasonable processing time compared to all other true ortho-photo generation methods tested in this paper.

The protective effects of steamed ginger on adipogenesis in 3T3-L1 cells and adiposity in diet-induced obese mice

  • Kim, Bohkyung;Kim, Hee-Jeong;Cha, Youn-Soo
    • Nutrition Research and Practice
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    • v.15 no.3
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    • pp.279-293
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    • 2021
  • BACKGROUND/OBJECTIVES: The steamed ginger has been shown to have antioxidative effects and a protective effect against obesity. In the present study, we investigated the effects of ethanolic extract of steamed ginger (SGE) on adipogenesis in 3T3-L1 preadipocytes and diet-induced obesity (DIO) mouse model. MATERIALS/METHODS: The protective effects of SGE on adipogenesis were examined in 3T3-L1 adipocytes by measuring lipid accumulations and genes involved in adipogenesis. Male C57BL/6J mice were fed a normal diet (ND, 10% fat w/w), a high-fat diet (HFD, 60% fat w/w), and HFD supplemented with either 40 mg/kg or 80 mg/kg of SGE for 12 weeks. Serum chemistry was measured, and the expression of genes involved in lipid metabolism was determined in the adipose tissue. Histological analysis and micro-computed tomography were performed to identify lipid accumulations in epididymal fat pads. RESULTS: In 3T3-L1 cells, SGE significantly decreased lipid accumulation, with concomitant decreases in the expression of adipogenesis-related genes. SGE significantly attenuated the increase in body, liver, and epididymal adipose tissue weights by HFD. Serum total cholesterol and triglyceride levels were significantly lower in SGE fed groups compared to HFD. In adipose tissue, SGE significantly decreased adipocyte size than that of HFD and altered adipogenesis-related genes. CONCLUSIONS: In conclusion, steamed ginger exerted anti-obesity effects by regulating genes involved in adipogenesis and lipogenesis in 3T3-L1 cell and epididymal adipose tissue of DIO mice.

Effects of antibacterial mouth rinses on multiple oral biofilms model (구강세정제가 다중 구강 바이오필름 모델에 미치는 영향)

  • Soo-Kyung Jun;Young-Suk Choi
    • Journal of Korean society of Dental Hygiene
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    • v.23 no.4
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    • pp.209-218
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    • 2023
  • Objectives: To confirm the antibacterial effects of each mouth rinse on multiple oral biofilms in vitro. Methods: The antibacterial effects of different mouth rinses were examined by ATP and counted colony forming units (CFU). Preformed oral biofilms on saliva coated hydroxyapatite (sHA) disks were treated with essential oil and saline; then, the multiple oral biofilms were observed by Scanning electron microscope (SEM). RNA sequencing analysis was performed on total RNA isolated from old biofilms of P. intermedia ATCC 49046. Results: In the CFU measured result compared to controls, preformed multiple oral biofilms were reduced from a low of 39.0% to 95.7% (p<0.05). The size of bacterial cells changed after treatment with the essential oil, and some of the cells ruptured into small pieces of cell debris. Gene expression in P. intermedia ATCC 49046 significantly altered in RNA transcribed and protein translated genes after exposure to essential oil. Conclusions: Mouth rinse solutions with different ingredients had different antibacterial effects and may alter surface structure and gene expression as determined by RNA sequencing.

Robinetin Alleviates Metabolic Failure in Liver through Suppression of p300-CD38 Axis

  • Ji-Hye Song;Hyo-Jin Kim;Jangho Lee;Seung-Pyo Hong;Min-Yu Chung;Yu-Geun Lee;Jae Ho Park;Hyo-Kyoung Choi;Jin-Taek Hwang
    • Biomolecules & Therapeutics
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    • v.32 no.2
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    • pp.214-223
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    • 2024
  • Metabolic abnormalities in the liver are closely associated with diverse metabolic diseases such as non-alcoholic fatty liver disease, type 2 diabetes, and obesity. The aim of this study was to evaluate the ameliorating effect of robinetin (RBN) on the significant pathogenic features of metabolic failure in the liver and to identify the underlying molecular mechanism. RBN significantly decreased triglyceride (TG) accumulation by downregulating lipogenesis-related transcription factors in AML-12 murine hepatocyte cell line. In addition, mice fed with Western diet (WD) containing 0.025% or 0.05% RBN showed reduced liver mass and lipid droplet size, as well as improved plasma insulin levels and homeostatic model assessment of insulin resistance (HOMA-IR) values. CD38 was identified as a target of RBN using the BioAssay database, and its expression was increased in OPA-treated AML-12 cells and liver tissues of WD-fed mice. Furthermore, RBN elicited these effects through its anti-histone acetyltransferase (HAT) activity. Computational simulation revealed that RBN can dock into the HAT domain pocket of p300, a histone acetyltransferase, which leads to the abrogation of its catalytic activity. Additionally, knock-down of p300 using siRNA reduced CD38 expression. The chromatin immunoprecipitation (ChIP) assay showed that p300 occupancy on the promoter region of CD38 was significantly decreased, and H3K9 acetylation levels were diminished in lipid-accumulated AML-12 cells treated with RBN. RBN improves the pathogenic features of metabolic failure by suppressing the p300-CD38 axis through its anti-HAT activity, which suggests that RBN can be used as a new phytoceutical candidate for preventing or improving this condition.

Nasal Immunization Using Chitosan Nanoparticles with Glycoprotein B of Murine Cytomegalovirus

  • Marcela Slovakova;Sylva Janovska;Radek Sleha;Vera Radochova;Alexandra Hatala;Nikola Mannova;Radovan Metelka;Ludovit Pudelka;Pavel Bostik
    • Journal of Microbiology and Biotechnology
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    • v.34 no.3
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    • pp.663-672
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    • 2024
  • The use of nanoparticles as a delivery system for a specific antigen could solve many limitations of mucosal vaccine applications, such as low immunogenicity, or antigen protection and stabilization. In this study, we tested the ability of nasally administered chitosan nanoparticles loaded with glycoprotein B of murine cytomegalovirus to induce an immune response in an animal model. The choice of chitosan nanoparticle type was made by in vitro evaluation of sorption efficiency and antigen release. Three types of chitosan nanoparticles were prepared: crosslinked with tripolyphosphate, coated with hyaluronic acid, and in complex with polycaprolactone. The hydrodynamic size of the nanoparticles by dynamic light scattering, zeta potential, Fourier transform infrared spectroscopy, scanning electron microscopy, stability, loading efficiency, and release kinetics with ovalbumin were evaluated. Balb/c mice were immunized intranasally using the three-dose protocol with nanoparticles, gB, and adjuvants Poly(I:C) and CpG ODN. Subsequently, the humoral and cell-mediated antigen-specific immune response was determined. On the basis of the properties of the tested nanoparticles, the cross-linked nanoparticles were considered optimal for further investigation. The results show that nanoparticles with Poly(I:C) and with gB alone raised IgG antibody levels above the negative control. In the case of mucosal IgA, only gB alone weakly induced the production of IgA antibodies compared to saline-immunized mice. The number of activated cells increased slightly in mice immunized with nanoparticles and gB compared to those immunized with gB alone or to negative control. The results demonstrated that chitosan nanoparticles could have potential in the development of mucosal vaccines.