• Applied Microscopy
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• v.45 no.3
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• pp.150-154
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• 2015

Negative staining electron microscopy facilitates the visualization of small bio-materials such as proteins; thus, many electron microscopists have used this conventional method to visualize the morphologies and structures of biological materials. To achieve sufficient contrast of the materials, a number of imaging parameters must be considered. Here, we examined the effects of one of the fundamental imaging parameters, electron beam exposure time, on electron densities generated using transmission electron microscopy. A single site of a negatively stained biological sample was illuminated with the electron beam for different times (1, 2, or 4 seconds) and sets of micrographs were collected. Computational image processing demonstrated that longer exposure times provide better electron densities at the molecular level. This report describes technical procedures for testing parameters that allow enhanced evaluations of the densities of electron microscopy images.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.5
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• pp.79-91
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• 2008

Research was initiated to investigate germination characteristics of creeping bentgrass (CB, Agrostis palustris Huds.). Seven varieties of CB were evaluated with different experiments. An alternative environment condition requiring for a CB germination test by International Seed Testing Association (ISTA) was applied in the Experiment I, consisting of 8-hr light at $25^{\circ}C$ and 16-hr dark at $15^{\circ}C$(ISTA conditions). Experiment II was conducted under a room temperature condition of 5 to $25^{\circ}C$(natural conditions). In each experiment, data such as seed germinating vigor, early germination characteristics, germination speed and germination peak time were measured. Significant differences were observed in seed germinating vigor, early germination characteristics, germination speed and germination peak time. Seed germinating vigor was variable with different environments and varieties. It was 61.50 to 98.25% under ISTA conditions and 55.00 to 98.50% under natural conditions. There were considerable variations in early germination characteristics among CB varieties according to different conditions. Early germination characteristics indicated that all varieties were 1 to 4 days faster in germination under ISTA conditions, when compared with natural conditions. The germination speed, measured as days to seed germination of 70% and 90%, was much faster with Penn A-1, Penn A-4 and Penncross under ISTA conditions. But it was even faster with L-93 and Penncross when grown under natural conditions. Differences were also observed in germination peak time with varieties and growing conditions. It was 0.57 to 2.86 days under ISTA conditions and 0.74 to 1.74 days under natural conditions. Regardless of the environment conditions, the shortest variety was L-93 and the longest one T-1. Considering germinating vigor, early germination characteristics, germination speed and germination peak time, Penn A-1, Penn A-4 and Penncross were regarded as excellent varieties under ISTA conditions in terms of early establishment characteristics, while L-93, Penn A-1 and Penncross under natural conditions. These results suggest that an intensive germination test be needed prior to planting, for the early germinating vigor, germination speed and germination peak time. Also, a proper variety selection and comprehensive site analysis for the growing environmental conditions should be done before golf course construction.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.4
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• pp.71-80
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• 2001

In order to evaluate the effectiveness of the organic and natural farming techniques, the actual conditions of the techniques were surveyed and some crops were cultivated in situ. The contents of available $P_2O_5$, exchangeable $Ca^{2+}$ and organic matter of the organic and natural farming soil as well as soil pH were higher than those of the non-organic and non-natural farming soil, and especially the content of organic matter amounting 54.0 g/kg was dominant. Income of the farmers cultivating the different crops with the organic and natural farming was high in order of red pepper in vinyl house > cucumber in vinyl house > fruit(pear) > lettuce in vinyl house > rice. The agricultural materials used in organic and natural farming were ranged from 22 to 25 kinds, representing low pH amounted from 2.9 to 4.5 and low contents of fertilizer ingredients. The expense for purchasing the materials was from three to five times higher than that of soil testing plot. The yields of test crops in the organic and natural farming plots were lower than those of soil testing plot, and the efficiencies of the disease and pest control by the application of the substitutes for pesticide were lower than those by pesticides.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.1
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• pp.172-178
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• 2003

Two types of bolted lap joints, one with a viscoelastic layer and the other without the viscoelastic layer were chosen to analyze the dynamic characteristics of the joints with the mechanical properties of the bolts in the joints are considered as computational variables. The finite element method was used along with the modal testing to verify the PEM model. The results in the bolted lap joints reveal that the higher the Young's modulus for the bolts we use the higher the natural frequencies we obtain fur the joints. However, the natural frequency differences in the first and second mode are not substantial but become noticeable in the higher modes. Lower natural frequencies were obtained for the bolted lap joints with the viscoelastic layer when compared with those of the bolted lap joints without the viscoelastic layer. And the differences in the natural frequencies for the two types of joints are relatively small in the first and second mode whereas in the higher mode the differences become significant. The loss factors were observed to be significant especially in the second mode for the bolted lap joints with the viscoelastic layer.

• Journal of Ginseng Research
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• v.33 no.1
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• pp.48-54
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• 2009

Epileptifrom discharges were induced in the telencephalon of the adult zebrafish via perfusion with pentylenetetrazole (PTZ), bicuculline methiodide, kainic acid-treated artificial cerebrospinal fluid (aCSF), and $Mg^{2+}$-free aCSF. Ginseng total saponin [GTS ($50{\mu}g/ml$)] was shown to attenuate the occurrence rate of epilpetiform discharges by 50-75%, compared to the control. Ginsenoside $Rg_1$ ($130{\mu}M$) reduced the epileptiform discharges in the isolated telencephalon and delayed the occurrence of behavioral seizures observed from the adult zebrafish placed in the PTZ (10 mM)-containing aquarium water. However, Re was not effective in the suppression of epileptiform discharges and behavioral seizures. These results indicate that $Rg_1$ may be useful in the control of epileptiform discharges and effective in controlling behavioral seizures, and that the zebrafish can be used as a model animal for the testing of potential anticonvulsant drugs.

• Journal of the Institute of Convergence Signal Processing
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• v.11 no.2
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• pp.143-150
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• 2010

Markerless augmented reality system must have the capability to recognize and match natural objects both in indoor and outdoor environment. In this paper, a novel approach is proposed for extracting features and recognizing natural objects using visual descriptors and codebooks. Since the augmented reality applications are sensitive to speed of operation and real time performance, our work mainly focused on recognition of multi-class natural objects and reduce the computing time for classification and feature extraction. SIFT(scale invariant feature transforms) and SURF(speeded up robust feature) are used to extract features from natural objects during training and testing, and their performance is compared. Then we form visual codebook from the high dimensional feature vectors using clustering algorithm and recognize the objects using naive Bayes classifier.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2001.02a
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• pp.292-309
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• 2001

Modulus of elasticity, modulus of rigidity, damping ratio, and natural frequency of three varieties of boxthorn(Lycium chinense Mill) (Cheongyang #2, Cheongyang gugija, and Cheongyang native) branches were analyzed. Modulus of elasticity and modulus of rigidity of the boxthorn branch was determined using standard formula after simple beam bending and torsion test, respectively, using an universal testing machine. Damping ratio and natural frequency of branches were determined using a system consisted of an accelerometer, a PC equipped with A/D converter, and a software for data analysis. Relationship between the elastic modulus and branch diameter in overall varieties and branch types showed a good correlation (r$\cong$-0.81). There was, however, no correlation between torsional rigidity and branch diameter. The internal damping results were highly variable and the overall range of the damping ratio of the boxthorn branch was 0.014 -0.087, which indicated that the branch was a lightly damped structure. The natural frequency of the boxthorn branch was in the range of 89-363 rad/s for the overall varieties and branch types. A good correlation (r$\cong$0.82) existed between the natural frequency and branch diameter in overall varieties and branch type.

• Asian Journal of Business Environment
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• v.14 no.1
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• pp.15-22
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• 2024

Purpose: The development of natural batik dyes based on a combination of coconut fiber waste and avocado leaves using the extraction method is important to support the green economy and reduce chemical waste in Indonesia. Research design, data and methodology: The research explores the use of coconut fiber and avocado leaf waste extraction as a natural batik dye and conducts market testing to assess consumer satisfaction. Results: Indonesian batik exports are growing, but synthetic dye practices are causing a decline in demand. To address this, natural dyes are being explored, including coconut fiber waste and avocado leaf waste. Conclusion: Test results from washing at 40 degrees Celsius in terms of color changes and color staining, from sweat in terms of changes in acid color and changes in base color, to sunlight in terms of color fastness value, to heat to iron in terms of color change and color staining shows a value of 3-4 (quite good) and 4-5 (good), meaning that coconut fiber and avocado leaves waste can be used as natural batik dye.

• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.188-193
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• 2007

Semi-solvent type cleaning agents were prepared by mixing naphthenes, natural terpene oil, surfactant and water, and measured their physical properties. And also, cleaning efficiency for flux and grease was measured by gravimetric method. By measuring the physical properties, pH for cleaning agents were 6.0~6.7, surface tension, 27.4~28.4 dyne/cm, and wetting index, 8.65~12.46 (with water), 11.99~17.43 (without water). The cleaning agent composed of naphthene, 30 wt%, natural terpene oil, 45 wt%, surfactant, 13 wt%, co-surfactant, 12 wt%, and water, 0 wt% had the largest wetting index, and shown the most effective cleaning properties for flux (98.66%) and grease (93.44%). The conductivity with $0.5{\sim}0.9{\mu}s/cm$ to the cleaning agent containing small amount of water was found to form W/O type microemulsion.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.5
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• pp.1-17
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• 2014

Research was initiated to investigate early establishment characteristics and germination pattern of Kentucky bluegrass (KB, Poa pratensis L.) under natural room temperature and to analyze differences between alternative and natural conditions for a practical application. Fifteen cultivars of KB were evaluated in the study. Daily and cumulative germination pattern were measured and analyzed on a daily basis. Differences were observed in germination percentage, germination pattern, days to the first germination and days to 75% germination. Germination percentage was variable with cultivars at the end of study. It was 75.75 to 90.25% under natural condition. There were considerable variations in early germination characteristics and germination pattern among KB cultivars according to germination conditions. The first germination in all entries tested was initiated between 6 and 9 DAS (days after seeding) under ISTA (International Seed Testing Association) condition. But it was observed between 9 and 12 DAS under natural condition, being 3 to 5 days later as compared with ISTA condition. On the first date of a germinating process, the germination rate was 0.25% to 25.00% under ISTA condition, while 0.50% to 13.25% under natural condition. Days to the 75% germination were 15.08 to 28.80 DAS under ISTA condition and 17.78 to 28.75 DAS under natural condition. Midnight II, Excursion and Midnight were the fastest cultivars under ISTA condition, while Odyssey the fastest one under natural condition. Regardless of germination condition, the slowest cultivar was Voyager II, being over 4 weeks to 75% germination percentage. For the most cultivars, days to 75% germination under natural room temperature condition were 1 to 8 days slower than under ISTA condition. From this study information on differences in germination characteristics and pattern among cultivars would be usefully applied for KB establishment such as golf course construction. Prior to on-site seeding, a comprehensive germination test is practically recommended due to a possible decline in germination capability during domestic distribution and storage after import.