• Journal of the Korean Mathematical Society
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• v.59 no.4
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• pp.757-774
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• 2022

Let a and b be positive even integers. An even [a, b]-factor of a graph G is a spanning subgraph H such that for every vertex v ∈ V (G), d_H(v) is even and a ≤ dH(v) ≤ b. Let κ(G) be the minimum size of a vertex set S such that G - S is disconnected or one vertex, and let σ₂(G) = min_uv∉E(G) (d(u)+d(v)). In 2005, Matsuda proved an Ore-type condition for an n-vertex graph satisfying certain properties to guarantee the existence of an even [2, b]-factor. In this paper, we prove that for an even positive integer b with b ≥ 6, if G is an n-vertex graph such that n ≥ b + 5, κ(G) ≥ 4, and σ₂(G) ≥ ${\frac{8n}{b+4}}$, then G contains an even [4, b]-factor; each condition on n, κ(G), and σ₂(G) is sharp.

• Journal of applied mathematics & informatics
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• v.28 no.3_4
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• pp.909-912
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• 2010

In this note we present a short proof of the following result by Zhou, Liu and Xu. Let G be a graph of order n, and let a and b be two integers with 1 $\leq$ a < b and b $\geq$ 3, and let g and f be two integer-valued functions defined on V(G) such that a $\leq$ g(x) < f(x) $\leq$ b for each $x\;{\in}\;V(G)$ and f(V(G)) - V(G) even. If $n\;{\geq}\;\frac{(a+b-1)^2+1}{a}$ and $\delta(G)\;{\geq}\;\frac{(b-1)n}{a+b-1}$,then G has a connected (g, f)-factor.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.1
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• pp.38-49
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• 1988

This paper presented as follows results of laboratory model tests with various shaped footings on soil bed reinforced with the strips on the base of behaviour of soil structure according to the loads and triaxial test results reinforced with geotextiles. Their parameters studied were the effects on the bearing capacity of a footing of the first layer of reinforcement, horizontal and vertical spacing of layers, number of layers, tensile strength of reinforcement and iclination load to the vertical 1.Depending on the strip arrangement, ultimate bearing capacity values could be more improved than urreinforced soil and the failure of soil was that the soil structure was transfered from the macrospace to microspase and its arrangement, from edge to edge to face to face. 2.The reinforcement was produced the reinforcing effects due to controlling the value of factor of one and permeable reinforcement was never a barrier of drainage condition. 3.Strength ratio was decreased as a linear shape according to increment of saturation degree of soil used even though at the lower strength ratio, the value of M-factor was rot influenced on the strength ratio but impermeable reinforcement decreased the strength of bearing capacity. 4.Ultimate bearing capacity under the plane-strain condition was appeared a little larger than triaxial or the other theoretical formulars and the circular footing more effective. 5.The maximum reinforcing effects were obtained at U I B=o.5, B / B=3 and N=3, when over that limit only acting as a anchor, and same strength of fabric appeared larger reinforcing effects compared to the thinner one. 6.As the LDR increased, more and more BCR occurred and there was appeared a block action below Z / B=O.5, but over the value, decrement of BCR was shown linear relation, and no effects above one. 7.The coefficient of the inclination was shown of minimum at the three layers of fabrics, but the value of H / B related to the ultimate load was decreased as increment of inclination degree, even though over the value of 4.5 there wasn't expected to the reinforcing effects As a consequence of the effects on load inclination, the degree of inclination of 15 per cent was decreased the bearing capacity of 70 per cent but irnproved the effects of 45 per cent through the insertion of geotextile.

• Journal of Power Electronics
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• v.6 no.4
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• pp.330-339
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• 2006

This paper deals with novel electronic ballast based on single-stage power processing topology using a symmetrical half-bridge inverter and current injection circuit. The half-bridge inverter drives the output parallel resonant circuit and injects current through the power factor correction (PFC) circuit. Because of high frequency current injection and high frequency modulated voltage, the proposed circuit maintains the unity power factor (UPF) with low THD even under wide variation in ac input voltage. This circuit needs minimum and lower sized components to achieve the UPF and high efficiency. This leads to an increase in reliability of ballast at low cost. Furthermore, to reduce cost, the electronic ballast is designed for two series-connected fluorescent lamps (FL). The analysis and experimental results are presented for ($2{\times}36$ Watt) fluorescent lamps operating at 50 kHz switching frequency and input line voltage (230 V, 50 Hz).

• Journal of Digital Convergence
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• v.11 no.7
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• pp.201-207
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• 2013

The chirp signaling has been mainly used in radar systems due to its good correlation characteristics, and nowadays it is applied to real time locating system(RTLS). The RTLS with chirp signaling was chosen as a standard such as ISO/IEC 24730-5 and IEEE 802.15.4a. In this paper, the performance of a real time locating system with chirp signaling was evaluated and simulated with relative distance error rates. We considered three cases of S/I = -30[dB], -20[dB], and -10[dB] with Rician factor K=10 and K=20. The performance was enhanced with K factor improvement by 25%, 27% and 50% for respective three cases of S/I. As results, in case of S/I < -20[dB], the minimum signal power is required for performance improvement even though the line of sight component is helpful. And also, in case of S/I ${\geq}$ -20[dB], as the line of sight component is stronger the better performance is obtained.

• Current Photovoltaic Research
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• v.7 no.3
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• pp.55-60
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• 2019

Polymer:nonfullerene solar cells with an inverted-type device structure were fabricated by employing the bulk heterojunction (BHJ) active layers, which are composed of poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophene-2-yl)-benzo[1,2-b:4,5-b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5',7-bis(2-ethylhexyl)benzo[1',2'-c:4',5'-c']dithiophene-4,8-dione))] (PBDB-T) and 3,9-bis(6-methyl-2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2',3-d']-s-indaceno[1,2-b:5,6-b']dithiophene (IT-M). The BHJ layers were formed on a pre-patterned indium-tin oxide (ITO)-coated glass substrate by spin-coating using the blend solutions of PBDB-T and IT-M. The solar cell performances were investigated with respect to the cell position on the ITO-glass substrates. In addition, the short-term shelf lifetime of solar cells was tested by storing the PBDB-T:IT-M solar cells in a glovebox filled with inert gas. The results showed that the performance of solar cells was relatively higher for the cells close to the center of substrates, which was maintained even after storage for 24 h. In particular, the PCE of PBDB-T:IT-M solar cells was marginally decreased after storage for 24 h owing to the slightly reduced fill factor, even though the open circuit voltage was unchanged after 24 h.

• Korean Journal of Pharmacognosy
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• v.24 no.4
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• pp.304-308
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• 1993

A platelet activating factor(PAF) antagonist ginkgolides produced from Ginkgo biloba are well known for their potential usage in septic shock and other PAF related diseases. Even though they are extracted from the leaves and on occasion the root bark, the exact biosynthetic site and pathway have not proved yet. In order to locate the enzymes involved and elucidate the biosynthetic site of the compounds, embryo-derived aseptic intact plantlet and plantlet without root have been cultured on 0.3% active carbon-containing solid Murashige and Skoog's medium. The leaves from the six-week-old normal plantlet contained similar amount of ginkgolide B to that of outdoor plant leaves, while the plantlets without root had less than 30% of the ginkgolide B compared to the in vitro intact plantlets. The results suggest that the ginkgolides may be synthesized in the root and transported to the aerial part.

• The Journal of the Korea Contents Association
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• v.22 no.4
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• pp.700-705
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• 2022

Hemophilia is a congenital hemorrhagic disease in which blood clotting is impaired and hemostatic abnormalities occur when even one of the 13 factors required for blood clotting are deficient. Among the 13 factors, hemophilia A (factor 8), hemophilia B (factor 9), and hemophilia C (factor 10), depending on the deficient coagulation factor. A male patient in his 40s diagnosed with hemophilia A visited the dentist at Eulji University Hospital for problems with alveolar bone absorption and periodontal abscess caused by overall chronic tooth inflammation, and showed overall bone absorption and inflammation at the time of initial diagnosis. No complications or bleeding tendency were observed in the rest of the area except for #35 and #36 due to regular visits for 10 years, overall good oral conditions, and no side effects or complications were observed.

• Nutrition Research and Practice
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• v.5 no.1
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• pp.34-39
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• 2011

The purpose of this study was to assess vitamin $B_6$ intake and status in Korean patients with newly diagnosed type 2 diabetes. Sixty-four patients with newly diagnosed type 2 diabetes and 8-11% glycated hemoglobin (A1C), along with 28 age-matched non-diabetic subjects, participated. Dietary vitamin $B_6$ intake was estimated by the 24 hour recall method and plasma pyridoxal 5'-phosphate (PLP) was measured. There was a significant difference in daily total calorie intake between the diabetic and non-diabetic groups ($1,917{\pm}376$ vs $2,093{\pm}311\;kcal$). There were no differences in intake of total vitamin $B_6$ ($2.51{\pm}0.91$ vs $2.53{\pm}0.81\;mg/d$) or vitamin $B_6$/1,000 kcal ($1.31{\pm}0.42$ vs $1.20{\pm}0.32\;mg$) between the diabetic and non-diabetic groups, and I intakes of total vitamin $B_6$ were above the Korean RDA in both groups ($180.0{\pm}57.9$ vs $179.0{\pm}65.4$). There was a higher percentage of diabetic subjects whose plasma PLP concentration was < 30 nmol/L compared to non-diabetic group. Plasma PLP levels tended to be lower in the diabetic subjects than in the non-diabetic subjects, although the difference was not statistically significant due to a large standard deviation ($80.0{\pm}61.2\;nmol/L$ vs $68.2{\pm}38.5\;nmol/L$). Nevertheless, plasma PLP levels should be monitored in pre-diabetic patients with diabetic risk factors as well as in newly diagnosed diabetic patients for long-term management of diabetes, even though this factor is not a major risk factor that contributes to the development of degenerative complications in certain patients.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.2
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• pp.307-312
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• 2010

Sugar snap cookies were prepared with the addition of carrot powder (2~12%) as a source of dietary fiber. Analyses of physiochemical properties, rheology and sensory evaluation of the cookies were conducted. Increasing carrot powder content weakened the flour, as evidenced by decreased diameter and increased thickness, which resulted in decreased spread factor. The water content of the carrot powder-amended cookies and unamended flour was not significantly different. The pH and L values progressively decreased and a and b values progressively increased with increasing addition of carrot powder. Textural analysis revealed no significant differences in brittleness with carrot powder addition, even though brittleness did decrease with the addition of more carrot powder. Sensory evaluation revealed a preference for cookies prepared with 2~4% carrot powder, with decreased preference at powder concentrations exceeding 6%. Addition of a dried vegetable with high fiber content caused the dietary fiber to absorb much water content, resulting in decreased diameter, increased thickness and decreased spread factor. Therefore, it is deemed desirable to increase the spread factor by controlling the water content and adding emulsifiers so as to enhance the functionality and maintain the quality of cookies.