• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.343-370
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• 2023

Developing improved wheat varieties is vital for global food security to meet the rising demand for food. Therefore, assessing the genetic diversity across wheat genotypes is crucial. This study examined the diversity of 168 durum wheat and 47 common wheat collections from 54 different countries using twelve agro-morphological parameters. Geumgang, a prominent Korean common wheat variety, was used as a control. Both qualitative and quantitative agronomical characteristics showed wide variations. Most durum wheats were shown to possess dense spikes (90%), while common wheats showed dense (40%) or loose (38%) spikes, with yellowish-white being the dominant spike color. The majority of the accessions were awned regardless of wheat type, yellowish-white being the main awn color. White or red kernels were produced, with white kernels dominating in both common (74%) and durum (79%) wheats. Days to heading (DH) and days to maturity (DM) were in the ranges of 166-215 and 208-250 days, respectively, while the culm length (CL), spike length (SL), and awn length (AL) were in the ranges of 53.67-163, 5.33-18.67, and 0.50-19.00 cm, respectively. Durum wheats possessed the shortest average DH, DM, and SL, while common wheat had the longest CL and AL (p < 0.05). Common wheats also exhibited the highest average one-thousand-kernel weight. Hierarchical cluster analysis, aided by principal component analysis, grouped the population into seven clusters with significant differences in their quantitative variables (p < 0.05). In conclusion, this research revealed diversity among common and durum wheat genotypes. Notably, 26 durum wheat and 17 common wheat accessions outperformed the control, offering the potential for developing early-maturing, high-yielding, and lodging-resistant wheat varieties.

• The Korean Journal of Ecology
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• v.9 no.1
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• pp.91-101
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• 1986

To investigate the distribution of Plantago asiatica Linne, almost, restricted on the road-side, the plant growth analyzed by experimental cultivation under the condition of tread-pressure; 10 times/day (7.33kg/$cm^2$ ), 20 times/day (12.27kg/$cm^2$), 30 times/day (20.05kg/$cm^2$ ) and the control plot (1.68kg/$cm^2$ ). The matter production in the 10-time-per-diem plot (7.33kg/$cm^2$ ) of tread-pressure howed more large value than that inthe control one (1.68kg/$cm^2$ ) and those in the 20-0time-per-diem plot (12.27kg/$cm^2$ ) and the 30-time-per-diem one (20.05kg/$cm^2$ ) small values than that of the control plot. Especially, the growth of roots and spikes was extremely repressed. The number of leaves, scapes and lateral buds tend to increase in the tread-pressure of 20 times/day (12.27kg/$cm^2$ ) and 30 times/day (20.05kg/$cm^2$ ). The water contents of roots along the increase of tread-pressure to continuosly decreased. By the increase of tread-pressure, T/R ratio and C/F ratio their group decreased. The plant growth (7.33kg/$cm^2$ ) in the 10-time-per-diem plot increased more than that in the control one is regarded as the effect of tread-pressure affection on the road-side distribution of this plant.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.1
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• pp.1-5
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• 2017

This study investigated the mechanical tearing of a cell membrane using a nanostructured alumina filter for easy and quick mechanical cell disruption. Nanostructured alumina filters were prepared by a multi-step aluminum anodizing process and nanopore etching process. Six different types of nanostructures were formed on the surface of the nanoporous alumina filters to compare the mechanical cell disruption characteristics according to the shape of the nanostructure. The prepared alumina filter was assembled in a commercial filter holder, and then, NIH3T3 fibroblast cells in a buffer solution were passed through the nanostructured alumina filter at a constant pressure. By measuring the concentration of proteins and DNA, the characteristics of mechanical cell disruption of the nanostructured alumina filter were investigated.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.73-78
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• 2000

This study was conducted for 2 years at Chinju region to establish suitable seeding rate and fertilizing levels of nitrogen, phosphorous and potassium in spring-sown Jinyangbori. Heading and maturing were delayed by increasing fertilizers, especially nitrogen. Number of spikes per were secured by much seeding and increased application of nitrogen. One thousand grain weight reduced with increasing fertilization at any seeding rate. Relatively high harvest indices were observed with 12-10-4 at 10kg. 10a$^{-l}$ seeds planted, followed by 6-10-8 at 15 kgㆍ 10a$^{-1}$, and 6-10-4kgㆍ 10a$^{-l}$ at 20kg ㆍ 10a$^{-l}$ of N-P-K fertilizing combinations, respectively. There was no distinct differences on yield for various seeding rates in spring-sown barley. When seeding rate increased up to 15kgㆍ10a$^{-1}$, the positive effect of fertilizers was recognized as the function of balanced-application. It was possible to recommend 10kgㆍ10a$^{-1}$ as seeding rate and 6-5-4(N-P-K)kgㆍ10a$^{-1}$ as fertilizing combination in spring-time seeding considering low input and sustainable agriculture. There was no significant difference of protein content in grain by seeding rate. Increase of nitrogen fertilizer enhanced protein content in grain.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.409-412
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• 2005

Just as the vibration modes of a beam are dependent on its end constraints or boundary conditions. Vibration modes of a tire are dependent on its patch and spindle constraints. This dependence is key to understanding the dynamic properties of a tire and is apparent in various analytical and experimental investigations in the literature. One of the main task in a modal analysis is the measurement of the Frequency Response Function (FRFs). Because all the subsequent analysis is based on these FRFs, their quality is critically important in obtaining accurate modal parameter estimates. In rotating systems, FRFs are frequently contaminated by harmonic peaks related to such factors as imbalance, misalignment. This harmonic peaks appear in the FRFs as sharp spikes, which can be erroneously treated in modal curve-fitting procedures as structural modes. The harmonic peaks removal method is demonstrated by application to modal analysis on rotating tires. The results show substantial improvement in FRF quality.

• Journal of Power Electronics
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• v.9 no.5
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• pp.736-747
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• 2009

A new type of single-phase Z-source AC/AC converter based on a single-phase matrix converter is proposed in this paper. The proposed single-phase Z-source AC/AC converter has unique features; namely that the output voltage can be bucked and in-phase/out-of-phase with the input voltage; that the output voltage can be boosted and in-phase/out-of-phase with the input voltage. The converter employs a safe-commutation strategy to conduct along a continuous current path, which results in the elimination of voltage spikes on switches without the need for a snubber circuit. The operating principles of the proposed single-phase Z-source AC/AC converter are described, and a circuit analysis is provided. To verify the performance of the proposed converter, a laboratory prototype based on a TMS320F2812 DSP was constructed. The simulation and the experimental results verified that the output voltage can be bucked-boosted and in-phase with the input voltage, and that the output voltage can be bucked-boosted and out-of-phase with the input voltage.

• Korean Journal of Clinical Laboratory Science
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• v.42 no.2
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• pp.97-102
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• 2010

The two new female cases of Angelman syndrome (AS) were described, which diagnosed on the basis of clinical features (dysmorphic facial features, severe mental retardation with absent speech, peculiar jerky movements, ataxic gait and paroxysms of inappropriate laughter) and neurophysiological findings. Failure to detect the deletion of the long arm of chromosome 15 or the absence of epileptic seizure were not considered sufficient to exclude a diagnosis of AS. Feeding problems, developmental delay and early signs of ataxia, especially tremor on handling objects and unstable posture when seated, proved effective as the clinical markers for early diagnosis of AS. Most of the authors agreed about the existence of three main EEG patterns in AS which may appear in isolation or in various combinations in the same patient. The most frequently observed pattern in children has prolonged runs of high amplitude rhythmic 2-3 Hz activity predominantly over the frontal region with superimposed interictal epileptiform discharges. High amplitude rhythmic 4-6 Hz activity, prominent in the occipital regions, with spikes, which can be facilitated by eye closure, is often seen in children under the age of 12 years. The EEG findings are characteristic of AS when seen in the appropriate clinical context and can be helpful to identify AS patients at an early age when genetic counselling may be particularly important.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.8
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• pp.1172-1180
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• 2017

This study analyzed competition in peak load plants between CCGT and GT instead of competition between base and peak load plants like in previous studies. In common overseas power markets, CCGT and GT claim certain market shares as peak load plants with the latter boasting a high utilization rate as reserve plants. In South Korea, however, there has been no introduction of GT in the market that opened in 2001 with no analysis cases of GT's economy as a peak load plant. The current power market of South Korea is run on the cost-based pool, which allows for no price spikes. Since the capacity payment criteria for compensations for missing money are set based on GT generators, the power market uses GT generators as marginal plants. The purposes of this study were to analyze the competitive edge of GT generators as peak load plants in the domestic power market of South Korea and identify the causes of GT's failure in market entry, thus assessing the adequacy of market signals in the domestic power market.

• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.2
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• pp.123-127
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• 1988

Even though grass species are one of major importance in livestock industry, the response of intergeneric hybridization of Lolium and Festuca and interspecific hybridization of Lolium m.X Lolium p. to Korean climatic condition has not been adequately documented. This reasearch was conducted to examine the growth characteristics and dry matter yield of Festulolium, cv. Felopa and C-Stamm N 66 and hybrid ryegrass, cv. Maja and Tetilelite. 1. The early growth of Italian ryegrass was better than that of hybrid ryegrass and Festulolium. The plant length and height of Italian ryegrass were longer/taller than those of hybrid ryegrass and Festulolium, but the number of tillers of Italian ryegrass was less than that of hybrid ryegrass and Festulolium. 2. Festuloliu and hybrid ryegrass were more tolerant than Italian ryegrass to winter killing, 70-80% of tillers was survived. 3. After wintering, early spring growth of hybrid ryegrass and Festulolium were better than that of Italian ryegrass. Dry matter yield of hybrid ryegrass and Festulolium were more than that of Italian ryegrass. 4. Spikes of hybrid ryegrass and Festulolium (C-Stamm N66) were more than those of Italian ryegrass. Seed yield per $m^2$ of hybrid ryegrass and Italian ryegrass were almost same, but that of Festuloliu was lower.

• Journal of Biomedical Engineering Research
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• v.34 no.4
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• pp.177-181
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• 2013

It is known that ultrasound affects action potentials in neurons, but the underlying principles of ultrasonic neural stimulation are not clearly elucidated yet. In this study, we measured the action potentials of rat hippocampal neurons cultured on multi-electrode arrays during ultrasound stimulation. From most of electrodes, it was observed that the ultrasound stimulation increased the frequencies of action potentials (i.e., spikes) during ultrasound stimulation.