• Title/Summary/Keyword: Added Mass Effect

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Aerodynamic behaviour of double hinged articulated loading platforms

  • Zaheer, Mohd Moonis;Hasan, Syed Danish;Islam, Nazrul;Aslam, Moazzam
    • Ocean Systems Engineering
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    • v.11 no.1
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    • pp.17-42
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    • 2021
  • Articulated loading platforms (ALPs) belongs to a class of offshore structures known as compliant. ALP motions have time periods falling in the wind excitation frequency range due to their compliant behaviour. This paper deals with the dynamic behavior of a double hinged ALP subjected to low-frequency wind forces with random waves. Nonlinear effects due to variable submergence, fluctuating buoyancy, variable added mass, and hydrodynamic forces are considered in the analysis. The random sea state is characterized by the Pierson-Moskowitz (P-M) spectrum. The wave forces on the submerged elements of the platform's shaft are calculated using Morison's Equation with Airy's linear wave theory ignoring diffraction effects. The fluctuating wind load has been estimated using Ochi and Shin wind velocity spectrum for offshore structures. The nonlinear dynamic equation of motion is solved in the time domain by the Wilson-θ method. The wind-structure interactions, along with the effect of various other parameters on the platform response, are investigated. The effect of offset of aerodynamic center (A.C.) with the center of gravity (C.G.) of platform superstructure has also been investigated. The outcome of the analyses indicates that low-frequency wind forces affect the response of ALP to a large extent, which otherwise is not enhanced in the presence of only waves. The mean wind modifies the mean position of the platform surge response to the positive side, causing an offset. Various power spectral densities (PSDs) under high and moderate sea states show that apart from the significant peak occurring at the two natural frequencies, other prominent peaks also appear at very low frequencies showing the influence of wind on the response.

The relationship between Customized SMEs R&D Support and Job Creation

  • Bae, Sang-Jin;Ko, Chang-Ryong
    • The Journal of Economics, Marketing and Management
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    • v.6 no.1
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    • pp.17-24
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    • 2018
  • Purpose - Major countries in the world continue to grow up without employment by the economy opening, more investment in foreign countries and technical innovation. Nevertheless, SMEs have job creation continuously. As this result, support for SMEs that is the source of job creation has increased attention. However, previous research between SMEs and job-creating is limited to the job creation effect of comparing with large companies, and R&D investment effect including government support. Also, many research provides the different result of correlation with technology innovation and job creation. Therefore, previous research has insufficient to explain job creation by which in the technology commercialization stage and the job-specific workforce. Research design, data, and Methodology - This study investigated the impact of customized R&D support upon job creation by using questionnaires of SMEs R&D service of K-Institution from 2009 to 2013. In detail, we analyzed the relationship between the technology commercialization stage and the usefulness of customized R&D support. Also, we added the analyzed the relationship between the usefulness of customized R&D support and the job-specific workforce. Results - Research result, Job creation had a significant relation to the usefulness of customized R&D support in product design stage and mass production stage. Also, R&D worker and production worker correlated with the usefulness of customized R&D support. These results indicate the importance of hiring R&D workers and production workers at the higher technology readiness. Conclusions -Therefore, this study suggests some implications for the government's SMEs support policy and the solve employment problems such as youth unemployment.

The Effect of Additives on the High Current Density Copper Electroplating (고전류밀도에서 첨가제에 따른 구리도급의 표면 특성 연구)

  • Shim, Jin-Yong;Moon, Yun-Sung;Hur, Ki-Su;Koo, Yeon-Soo;Lee, Jae-Ho
    • Journal of the Microelectronics and Packaging Society
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    • v.18 no.1
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    • pp.29-33
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    • 2011
  • The current density in copper electroplating is directly related with the productivity and then to increase the productivity, the increase in current density is required. To obtain the high mass flow rate, rotating disk electrode(RDE) was employed. High rotational speed in RDE can increase the mass flow rate and then high speed electroplating was possible using RDE to control mass flow. Two types of cathode were used. One is RDE and another is rotating cylindrical electrode(RCE). A constant-current, constant-voltage and linear sweep voltammetry were applied to investigate current and voltage relationship. The maximum current density without evolution of hydrogen gas was increased with rotational speed. Over 400 rpm, maximum current density was higher than 1000 A/$m^2$. The diffusion coefficients of copper calculated from the slope of the plots are $5.5{\times}10^6\;cm^2\;s^{-1}$ at $25^{\circ}C$ and $10.5{\times}10^6\;cm^2\;s^{-1}$ at $62^{\circ}C$. The stable voltage without evolution of hydrogen gas was -0.05 V(vs Ag/AgCl). Additives were added to prevent dendritic growth on cathode deposits. The surface roughness was analyzed with UV-Vis Spectrophotometer. The reflectance of the copper surface over 600 nm was measured and was related with the surface roughness. As the surface roughness improved, the reflectance was also increased.

Analysis of Synthetic Fragrances (SFs) in Water Using Stir Bar Sorptive Extraction (SBSE) and GC-MS/MS (교반막대 추출법과 GC-MS/MS를 이용한 수중의 합성 향물질류 분석)

  • Seo, Chang-Dong;Son, Hee-Jong;Yoom, Hoon-Sik;Choi, Jin-Taek;Ryu, Dong-Choon;Kwon, Ki-Won;Jang, Seung-Ho
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.6
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    • pp.387-395
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    • 2014
  • A highly sensitive analytical method based on stir bar sorptive extraction (SBSE) technique and gas chromatography/tandem mass spectrometry (GC-MS/MS) has been developed, allowing the simultaneous multi-analyte determination of 11 synthetic fragrances (SFs) in water samples. The stir bar coated with polydimethylsiloxane (PDMS) was added to 40 mL of water sample at pH 3 and stirred at 1,100 rpm for 120 min. Other SBSE parameters (salt effect and presence of organic solvent) were optimised. The method shows good linearity (coefficients > 0.990) and reproducibility (RSD < 10.9%). The extraction efficiencies were above 83% for all the compounds. The limits of detections (LOD) and limits of quantification (LOQ) were 2.1~4.1 ng/L and 6.6~12.9 ng/L, respectively. The developed method offers the ability to detect 11 SFs at ultra-low concentration levels with only 40 mL of sample volume. Matrix effects in tap water, river water, wastewater treatment plant (WWTP) final effluent water and seawater were investigated and it was shown that the method is suitable for the analysis of trace level of 11 SFs. The method developed in the present study has the advantage of being rapid, simple, high-sensitive and both user and environmentally friendly.

Tandem Mass Spectrometric Analysis for Disorders in Amino, Organic and Fatty Acid Metabolism : 2 Years of SCL Experience in Korea

  • Yoon, Hye-Ran;Lee, Kyung Ryul
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.3 no.1
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    • pp.86-93
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    • 2003
  • Background : The SCL began screening of newborns and high risk group blood spots with tandem mass spectrometry (MS/MS) in April 2001. Our goal was to determine approximate prevalence of metabolic disorders, optimization of decision criteria for estimation of preventive effect with early diagnosis. This report describes the ongoing effort to identify more than 30 metabolic disorders by MS/MS in South Korea. Methods : Blood spot was collected from day 2 to 30 (mostly from day 2 to 10) after birth for newborn. Blood spot of high risk group was from the pediatric patients in NICU, developmental delay, mental retardation, strong family history of metabolic disorders. One punch (3.2 mm ID) of dried blood spots was extracted with $150{\mu}L$ of methanol containing isotopically labelled amino acids (AA) and acylcarnitines (AC) internal standards. Butanolic HCl was added and incubated at $65^{\circ}C$ for 15 min. The butylated extract was introduced into the inlet of MS/MS. Neutral loss of m/z 102 and parent ion mode of m/z 85 were set for the analyses of AA and AC, respectively. Diagnosis was confirmed by repeating acylcarnitine profile, urine organic acid and plasma amino acid analysis, direct enzyme assay, or molecular testing. Results : Approximately 31,000 neonates and children were screened and the estimated prevalence (newborn/high risk group), sensitivity, specificity and recall rate amounted to 1:2384/1:2066, 96.55%, 99.98%, and 0.73%, respectively. Confirmed 28 (0.09%) multiple metabolic disorders (newborn/high risk) were as follows; 13 amino acid disorders [classical PKU (3/4), BH4 deficient-hyperphenylalaninemia (0/1), Citrullinemia (1/0), Homocystinuria (0/2), Hypermethioninemia (0/1), Tyrosinemia (1/0)], 8 organic acidurias [Propionic aciduria (2/1), Methylmalonic aciduria (0/1), Isovaleric aciduria (1/1), 3-methylcrotonylglycineuria (1/0), Glutaric aciduria type1 (1/0)], 7 fatty acid oxidation disorders [LCHAD def. (2/2), Mitochondrial TFP def. (0/1), VLCAD def. (1/0), LC3KT def. (0/1). Conclnsion : The relatively normal development of 10 patients with metabolic disorders among newborns (except for the expired) demonstrates the usefulness of newborn screening by MS/MS for early diagnosis and medical intervention. However, close coordination between the MS/MS screening laboratory and the metabolic clinic/biochmical geneticists is needed to determine proper decision of screening parameters, confirmation diagnosis, follow-up scheme and additional tests.

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Study on the Additive Effect of Epidermal Growth Factor (EGF) and Expression of EGF-Receptor (EGF-R) on IVM/IVF Bovine Embryo Development (체외 생산된 소 수정란의 발달에 있어서 EGF 첨가제 효과와 EGF-R 발현에 관한 연구)

  • 김은영;김묘경;엄상준;윤산현;박세필;정길생;임진호
    • Korean Journal of Animal Reproduction
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    • v.20 no.3
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    • pp.279-288
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    • 1996
  • The objective of this study was to determine the effect of EGF on the development of IVM/IVF bovine embryos and their ICM and TE cell number. In addition, we examined the combined effect of EGF and coculture to the bovine embryo development and the expression of EGF-R protein on bovine embryos by indirect immunofluorescence. The results obtained in these experiments were summarized as follows: When the IVM/IVF 4- to 8-cell embryos were treated at 0, 1, 10, 100 ng/ml of EGF, EGF treatment group showed improved development to blastocyst and increased pattern of ICM and TE cell number compared with control, although there is not significantly different. The stimulating effect of EGF (10 ng/ml) to the develop ment level of IVM/IVF bovine embryos significantly increased development rate to blastocyst after 8-cell stage (p<0.05), although there is no significant effect to the increase of ICM and TE cell numbers. Also, expression of EGF-R on the bovine embryonic stage by indirect immunofluor escence presents after 4-cell stage and the intensity of the EGF-R staining was variable with the development progression. On the other hand, embryos cultured in coculture group added either with or without EGF commonly indicated the significant difference in development rate to blastocyst and Total cell number compared with control. These results suggest that the a addition of EGF to the coculture may stimulate the coculture effect between IVM/IVF bovineembryos and cumulus cells. Therefore, EGF could promote preimplantation bovine embryo development by binding with expressed EGF~R after 4-cell stage, and stimulate the production of embryotrophic factors from the coculture environment. Also, the present study showed that there was no significant effect of EGF to the increase of ICM and TE cell number although the rate of blastocyst significantly increased when treated with EGF after 8-cell stage (p<0.05).

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The Antifungal Effect of Rhus verniciflua Stokes against Metarhizium anisopliae on the Edible Insect, Protaetia brevitarsis (Coleoptera) (흰점박이꽃무지에 발생하는 병원성 곰팡이 Metarhizium anisopliae에 대한 옻나무 추출액의 항진균 효과)

  • Kim, Nang-Hee;Song, Myung-Ha;Kim, Eunsun;Kim, Yongsoon;Park, Kwan-Ho;Kim, Sunyoung
    • Korean Journal of Ecology and Environment
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    • v.53 no.4
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    • pp.374-379
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    • 2020
  • The white-spotted flower chafer (Protaetia brevitarsis) larva is one of the insects widely-used for edible and medicinal purposes in Eastern Asia. As a result of increasing demand for P. brevitarsis, massrearing systems in domestic farms have become necessary. However, the mass-rearing of larvae under confined rearing conditions could provide conditions unsuitable for preventing entomopathogenic diseases. Metarhizium anisopliae is the strongest fatal entomopathogenic fungus against P. brevitarsis. For inhibition of M. anisopliae, we used a Rhus verniciflua Stokes extract that has antifungal components. We investigated the inhibitory effect of the R. verniciflua extract at 1%, 5%, and 10% concentrations. The results showed that a 1% R. verniciflua extract added to sawdust produced a significantly low P. brevitarsis mortality rate. Moreover, extract-treated groups were heavier and had a shorter larval period than those of the untreated group. Consequently, we suggest that using an R. verniciflua extract can reduce the P. brevitarsis fatality rate from entomopathogenic fungi (e.g. M. anisopliae), resulting in more effective mass-rearing systems for P. brevitarsis.

Effect of Essential and Nonessential Amino Acids in North Carolina State University (NCSU)-23 Medium on Development of Porcine In vitro Fertilized Embryos

  • Hashem, Md. Abul;Bhandari, Dilip P.;Hossein, Mohammad Shamim;Jeong, Yeon Woo;Kim, Sue;Kim, Ji-Hye;Koo, Ok-Jae;Park, Seon Mi;Lee, Eu Gine;Park, Sun Woo;Kang, Sung Keun;Lee, Byeong Chun
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.5
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    • pp.693-700
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    • 2007
  • The present study was conducted to examine the effect of different levels of essential and nonessential amino acid in NCSU-23 medium on the in vitro-produced porcine embryo as it develops from the zygote to the blastocyst stage. Four experiments were performed, each with a completely randomized design involving 5 to 8 replications of treatments. In order to know the effect of nonessential amino acids in NCSU-23 medium, 0, 5, 10 and $20{\mu}/ml$ MEM were supplemented there to, (Exp. 1) and the medium was supplemented with same level of essential amino acids (Exp. 2). The combined effect of nonessential (0, 5, 10 and $20{\mu}/ml$ MEM) and essential amino acids (0, 5, 10 and $10{\mu}/ml$ MEM) in NCSU-23 medium (Exp. 3), first 72 h with non-essential amino acids (at 0, 5, 10 and $20{\mu}/ml$ MEM), and last 4 d with essential amino acids with the same level as NEAA (Exp. 4) were examined. The embryo development was monitored and the quality of blastocysts was evaluated by counting the number of total cells and determining the ratio of inner cell mass (ICM) to trophoectoderm (TE) cells. When Eagle's nonessential amino acids (MEM) added to NCSU-23 medium, it significantly increased the likelihood of development to the 2- to 4-cell stage and subsequent blastocyst development. Supplementation of different levels of essential amino acids in the NCSU-23 medium decreased cleavage rate, rate of morula and blastocyst development and the number of ICMs. In the case of the combined effect of essential and nonessential amino acids, better and significant results were found for blastocysts, hatching blastocysts and for ICM numbers which were also dose dependent. With respect to the biphasic effect of nonessential and essential amino acids, nonessential amino acids increased cleavage whereas essential amino acids increased the total cell number. Neither the nonessential nor the essential group of amino acids, on their own, affected blastocyst cell number or the differentiation of cells in the blastocyst. In conclusion, this study determined the role of nonessential and essential amino acids in the culture of the porcine embryo and showed that the embryo requires different levels of amino acids as it develops from the zygote to the blastocyst stage.

Effect of Sugars on Cell Growth and Lipase Production by Trichosporon cutaneum (Trichosporon cutaneum의 균체생육(菌體生育) 및 Lipase 생산(生産)에 미치는 당류(糖類)의 영향)

  • Kim, Seung-Yeol
    • Korean Journal of Agricultural Science
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    • v.4 no.1
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    • pp.105-111
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    • 1977
  • Inhibitory effect of sugars on lipase production by Trichosporon cutaneum was observed in the previous study (Kim, 1972), and inhibition was distinctive by the addition of glucose, fructose, mannose, xylose and arabinose to the soybean meal medium among various carbon sources. These experiments were carried out to study the effect of sugars on cell growth and lipase production by the strain using the soybean extracts liquid medium under a shaking culture system. Changes in color and pH of the medium were caused by heat sterilization when various sugars were added. To elucidate the possible effect of these coloring matters on lipase production and cell growth: changes in pH of the culture, cell concentration and level of the enzyme activities were determined when the culture was grown for 48 hours at $30^{\circ}C$ on a reciprocal shaker. The results obtained were as follows: 1. Density of brownish color which formed during heat sterilization was varied with the variety of sugar used, ie, strong in pentose such as xylose: weak in hexose such as galactose, mannose, glucose: very weak in disaccharide such as maltose, sucrose. When the color density was stronger, decrease in pH after sterilization was marked. 2. Cell growth and lipase production was not so effect by the coloring matters as by sugars. 3. The more the cell mass of the culture, the lower the level of lipase production in the culture supernatant. 4. Among the sugars which caused the distinctive inhibition of lipase production, a slight relief of inhibition was noticed by the addition of xylose, whereas the cell growth was repressed. 5. When cell growth was better, decrease in pH of the medium was greater during cultivation.

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Hormonal Study to Induce Direct Organ Differentiation of Kalanchoe pinnata by Tissue Culture (조직배양으로 Kalanchoe pinnata의 직접기관분화를 유도하기 위한 호르몬 연구)

  • Kim, Donggiun
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.4
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    • pp.721-726
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    • 2021
  • Plant cells have a totipotencial capacity, the ability of each cell to produce a new complete individual through development. By applying this, several technologies are being developed for widespread application of somatic embryogenesis by processing hormones in vitro as a method of propagation of plants. In order to use this technology, in Kalanchoe pinnata, a plant capable of asexual reproduction with more regular cell division, kinetin belonging to cytokinin and picloram among hormones belonging to auxin were added in combination and treated for 8 weeks, and then the typical performance was evaluated. As a result of our experiment, the rooting effect in leaf slices showed a 70% incidence rate at a picloram concentration of 0.1 mg/L. It has been proven that a concentration difference of 1:5-1:10 in the ratio of kinetin and picloram is effective. It is the experimental result that the effect of auxin is essential for the development of Kalanchoe roots. As for the effect of shooting, the incidence rate was 60% at the picloram concentration of 0.5 mg/L. The kinetin concentration from 0.5 and 1.0 mg/L and has a significant effect on development. It has been proven that the ratio of kinetin to picloram is effective with a concentration difference of 1:1-1:2. These results show that the combination of cytokinin and auxin is crucially important for shooting. It is thought that it can be the basis of a technology for inducing mass proliferation in vitro by inducing direct organogenesis with a combination of hormones.