• Korean Journal of Optics and Photonics
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• v.34 no.5
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• pp.192-201
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• 2023

The band-limited angular spectrum method (BL-ASM) causes aliasing errors due to spatial frequency control problems. In this paper, a sampling interval adjustment technique for phase holograms and a technique for reducing speckle noise and improving image quality using a deep-learningbased U-net model are proposed. With the proposed technique, speckle noise is reduced by first calculating the sampling factor and controlling the spatial frequency by adjusting the sampling interval so that aliasing errors can be removed in a wide range of propagation. The next step is to improve the quality of the reconstructed image by learning the phase hologram to which the deep learning model is applied. In the S/W simulation of various sample images, it was confirmed that the peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM) were improved by 5% and 0.14% on average, compared with the existing BL-ASM.

• Journal of Animal Science and Technology
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• v.62 no.5
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• pp.648-658
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• 2020

The objective of the study was to evaluate the effects of Lactobacillus, cellulase, and molasses on chemical composition, fermentation qualities, and microorganism count of sugarcane bagasse silage after 30-days fermentation. The treatments were arranged according to a factorial arrangement (2 × 2 × 2) + 1, in a complete randomized design. The first factor consisted of two levels of Lactobacillus casei TH14 (TH14, 0 and 0.05 g/kg fresh matter; the second factor consisted of two levels of cellulase enzyme (C, 0 and 10⁴ U/kg fresh matter); and the third factor consisted of two levels of molasses (M, 0 and 5 g/ 100 mL distilled water). A treatment (+1) referred to the use of rice straw without any treatments. The result showed that dry matter increased by 4% and neutral detergent fiber decreased by 2% of sugarcane bagasse when ensiled as a combination of additives as compared to untreated sugarcane bagasse. The pH and ammonia nitrogen were significantly dropped to 3.5 and 2.3 g/kg dry matter. Furthermore, lactic acid was increased by 64% when compared to untreated sugarcane bagasse, respectively. Lactic acid bacteria count was increased by 28% as compared to untreated sugarcane bagasse. Based on this experiment, fermenting with L. casei TH14, cellulase, and molasses in combination resulted in the promotion of the best qualities of sugarcane bagasse silage.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.478-484
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• 1996

Recombinant human epidermal growth factor (rhEGF) was produced by E. coli BL21 harboring a plasmid pYHB101. The maximum production was 68.7 mg/l when the E. coli strain was cultured at 25$\circ$C for 48 hours in the modified MBL medium containing 10 g/l glucose with 1 mM IPTG induction at 2 hours after inoculation. The rhEGF was purified upto 267 folds by Amberlite XAD- 7 chromatography, ultrafiltration, and DEAE Sepharose fast flow ion exchange chromatography with an overall yield of 66.6%. The purified rhEGF was further separated into two fractions by HPLC. The N-terminal amino acid sequence of the second fraction was Asn-Ser-Asp-Ser-Glu-Cys-Pro-Leu-Ser-His. The effect of rhEGF on the DNA synthesis was examined using in vitro biological assay based on the incorporation of 5'-bromo-2'- deoxy-uridine (BrdU). The purified rhEGF shows no difference with natural human epidermal growth factor (nhEGF) in N-terminal amino acids residues and biological activity. From the results, we concluded that rhEGF produced from E. coli harboring the plasmid pYHB101 was apparently the same as nhEGF.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.1
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• pp.185-194
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• 1997

An experimental study has been performed on the effect of baffle parameters on shell -side heat transfer in a conventional shell-and-tube heat exchanger. The baffle spacing distance and the number of baffle were varied to investigate the behavior of unequal baffle spacing correction factor which is appeared in the Bell Delaware method for prediction of the shell-side heat transfer coefficient. It was obvious that heat duties obtained from the experiment significantly deviated from those calculated by the conventional Bell-Delaware method. A new correlation of the unequal baffle spacing correction factor was developed. It was shown that the new correlation improves the accuracy of the Bell-Delaware method considerably. This result may induce the use of the Bell-Delaware method in developing a computer software for design of shell-and-tube heat exchangers.

• Korean Journal of Environmental Agriculture
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• v.13 no.2
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• pp.209-215
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• 1994

Absorption, translocation, and metabolism of the herbicide alachlor in soybean, Chinese cabbage, and barnyard grass seedlings were examined and compared with each other using [phenyl-U-$^{14}C$] alachlor in search of a primary factor contributing to the selectivity of alachlor. When root of each seedling was immersed into the solution containing [$^{14}C$]alachlor, the amount of absorbed radioactivity/mg dry matter of seedling which was suggested to be correlated with the susceptibility of plants to alachlor decreased in the order of soybean ${\gg}$ Chinese cabbage ${\geq}$ barnyard grass and the rate of translocation to shoot was Chinese cabbage ${\geq}$ barnyard grass ${\gg}$ soybean. These orders did not consistently explain the selective phytotoxicity of alachlor. Analyses of extracts by reverse phase chromatography showed that alachlor was detoxified by conjugation with glutathione in all three plants and the rate of glutathione conjugation of soybean, the resistant species to alachlor, was the greatest, while that of barnyard grass, the susceptible, was the lowest among three plants. This result explained well the selective phytotoxicity of alachlor. Both absorption and translocation contribute undoubtedly to the selectivity by influencing the active internal concentration of alachlor. However, neither of them appeared to be a primary factor. It was concluded that the most important primary factor was the rate of glutathione conjugation, which detoxifies alachlor and plays an important role in selectivity.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.4
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• pp.549-559
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• 1999

An experimental study was peformed to measure the viscosity of microencapsulated PCM slurries as the functions of its concentration and temperature, and also influence to its fluid dynamics. For the viscosity measurement, a rotary type viscometer, which was equipped with temperature control system, was adopted. The slurry was mixed with water and Sodium Lauryl Sulphate as a surfactant by which its suspended particles were dispersed well without the segregation of particles during the experiment. The viscosity was increased as the concentration of MicroPCM particle added. The surfactant increased 5% of the viscosity over the working fluid without particles. Experiments were proceeded by changing parameters such as PCM particles'concentration as well as the temperature of working fluid. As a result, a model to the functions of temperature for the working fluid and its particle concentration is proposed. The proposed model, for which its standard deviation shows 0.8068, is agreed well with the reference's data. The pressure drop was measured by U-tube manometer, and then the friction factor was obtained. It was noted that the pressure drop was not influenced by the state of PCM phase, that is solid or liquid in its core materials at their same concentration. On the other hand, it was described that the pressure drop of the slurry was much increased over the working fluid without particles. A friction factor was placed on a straight line in all working fluids of the laminar flow regardless of existing particles as we expected.

• International Journal of Knowledge Content Development & Technology
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• v.8 no.3
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• pp.29-40
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• 2018

This paper discussed motivation, some theories of motivation and motivation of library personnel. The most important aspect of any organization is its workforce. Motivation arouses, energizes, influences and sustains behaviour and performance of employees. Motivating factors include extrinsic factors which pertain to the conditions under which a job is performed and intrinsic motivators which contribute to job satisfaction and subsequently increase productivity. Two levels of motivation were identified in the library: the need-factor motivation and the profession-related motivation. Need-factor motivation is well-pronounced in the lower cadre of library staff such as library assistants, clerical staff, and porters who set their priority on economic needs. The profession-related motivation occurs among professionally trained librarians whose motivation hinges self-fulfillment derived from professional growth and development. Other motivating factor in the library is job design which includes job rotation, job enlargement, and job enrichment. Job design specifies the contents or methods of any job in such a way that various requirements of a job can be effectively satisfied. Adequate motivation of library employees lies with the managers because they generally control work distribution, freedom and autonomy, work challenge Remove, staff development and training, and advancement opportunities. The managers are urged to create enabling environment to ensure improved commitment, satisfaction, and productivity of employees in the library.

• Journal of the Korean Society of Safety
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• v.6 no.4
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• pp.81-87
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• 1991

We propose the crack growth rate equation which will model fatigue crack growth rate behavior such that constant stress amplitude fatigue crack growth behavior can be predicted. Constant stress amplitude fatigue tests are conducted for four materials under three stress ratios of R＝0.2, R＝0.4 and R＝0.6. Materials which have different mechanical properties i.e. stainless steel, low carbon steel, medium carbon steel and aluminum alloy are used. Through constant stress amplitude fatigue test by using unloading elastic compliance method, it is confirmed that crack closure is a close relationship with fatigue crack propagation. We describe simply fatigue crack propagation behavior as a function of the effective stress intensity factor range ($\Delta$ $K_{eff}$＝U .$\Delta$K) for all three regions (threshold region, stable region). The fatigue crack growth rate equation is given by da / dN＝A($\Delta$ $K_{eff}$­$\Delta$ $K_{o}$ )$^{m}$ / ($\Delta$ $K_{eff}$­$\Delta$K) Where, A and m are material constants, and $\Delta$ $K_{o}$ is stress intensity factor range at low $\Delta$K region. $K_{cf}$ is critical fatigue stress intensity factor.actor.

• Korean Journal of Veterinary Research
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• v.52 no.2
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• pp.99-104
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• 2012

The present study was performed to evaluate the relationship between the neurotoxicity of acrylamide and the differential gene expression pattern in mice. Both locomotor test and rota-rod test showed that the group treated with higher than 30 mg/kg/day of acrylamide caused impaired motor activity in mice. Based on cDNA microarray analysis of mouse brain, myelin basic protein gene, kinesin family member 5B gene, and fibroblast growth factor (FGF) 1 and its receptor genes were down-regulated by acrylamide. The genes are known to be essential for neurofilament synthesis, axonal transport, and neuroprotection, respectively. Interestingly, both FGF 1 and its receptor genes were down-regulated. Genes involved in nucleic acid binding such as AU RNA binding protein/enoyl-coA hydratase, translation initiation factor (TIF) 2 alpha kinase 4, activating transcription factor 2, and U2AF 1 related sequence 1 genes were down-regulated. More interesting finding was that genes of both catalytic and regulatory subunit of protein phosphatases which are important for signal transduction pathways were down-regulated. Here, we propose that acrylamide induces neurotoxicity by regulation of genes associated with neurofilament synthesis, axonal transport, neuro-protection, and signal transduction pathways.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.2
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• pp.52-58
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• 2000

This paper presents a novel power factor corrected(PFC) single-stage AC/DC half-bridge converter, which features discontinuous conduction mode(DCM) and soft-switching. The reduced conduction losses are achieved by the employment of a novel powder factor correction circuitry, instead of the conventional configuration composed of a front-end rectifier followed by a boost converter. To identify the validity of the proposed converter, simulated results of 500[W] converter with 100[V] input voltage and 50[V]output voltage are presented.