• Advances in nano research
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• v.17 no.1
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• pp.75-86
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• 2024

The insecticidal efficiency of orange (Citrus sinensis) peel essential oil (OP-EO) is limited because of its low stability under environmental conditions. Nanoemulsion formulations show promise in overcoming this limitation. Therefore, this study aimed to formulate and characterize the OP-EO nanoemulsion form (OP-EON) and investigate its insecticidal properties against two significant storage pests, Rhyzopertha dominica (Fabricius, 1792), and Tribolium castaneum (Herbst, 1797). The OP-EON (4:3:3:90 w/w, EO: Tween 80: Ethanol: water) was successfully created using an ultrasonic homogenizer. The major chemical components of the OP-EO were determined to be D-limonene (87.93%), myrcene (3.62%), and α-pinene (1.34%) through GC-MS analysis. The OP-EON was characterized using TEM (50-100 nm), Zeta sizer (the mean droplet particle size of 58.60 nm, the ζ-potential value of -12.6 mV, and the polydispersity index of 0.486), and FT-IR analysis. After 7 days, exposure to 500 ppm of the OP-EON resulted in 50% and 30% mortality rates in R. dominica and T. castaneum, respectively. Exposure to 1000 ppm of OP-EON resulted in 90% and 55% mortality in R. dominica and T. castaneum, respectively, after 7 days. Overall, these results clearly showed the potential to exceed the limits of the insecticidal activity of the OP-EO with its nanoemulsion form.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.723-730
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• 2011

Soybean oil used to fry French fries, chicken nuggets, and donuts was exposed to high temperature at $180^{\circ}C$ for 72 h. The effects of frying foods on the thermooxidative stability of soybean oil were evaluated by determining the contents of free fatty acids, peroxides, total polar compounds, and conjugated dienoic acids, and by analyzing dielectric constant, refractive index, iodine value, smoke point, and fatty acid composition. The contents of free fatty acids, total polar compounds, conjugated dienoic acids, dielectric constant, and refractive index increased, whereas iodine value, smoke point, and U/S ratio of fatty acids composition decreased with frying time. All samples of frying oils after 72 h presented free fatty acid contents of below 2.0% and total polar compounds of below 25%, which were within the legal limits. However, peroxide values of frying oils were not directly correlated with frying time. The type of fried food affected the thermooxidative stability of the frying oils, with chicken nuggets being more stable in thermooxidation than French fries and donust. Among physiochemical indicators of frying oil quality, a rapid method including dielectric constant and refractive index can be used in quantity food production.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.144.2-144.2
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• 2016

Diamond-like carbon (DLC) coatings have been widely applied to the mechanical components, cutting tools due to properties of high hardness and wear resistance. Among them, hydrogenated amorphous carbon (a-C:H) coatings are well-known for their low friction properties, stable production of thin and thick film, they were reported to be easily worn away under high temperature. Non-hydrogenated tetrahedral amorphous carbon (ta-C) is an ideal for industrial applicability due to good thermal stability from high $sp^3$-bonding fraction ranging from 70 to 80 %. However, the large compressive stress of ta-C coating limits to apply thick ta-C coating. In this study, the thick ta-C coating was deposited onto Inconel alloy disk by the FCVA technique. The thickness of the ta-C coating was about $3.5{\mu}m$. The tribological behaviors of ta-C coated disks sliding against $Si_3N_4$ balls were examined under elevated temperature divided into 23, 100, 200 and $300^{\circ}C$. The range of temperature was setting up until peel off observed. The experimental results showed that the friction coefficient was decreased from 0.14 to 0.05 with increasing temperature up to $200^{\circ}C$. At $300^{\circ}C$, the friction coefficient was dramatically increased over 5,000 cycles and then delaminated. These phenomenon was summarized two kinds of reasons: (1) Thermal degradation and (2) graphitization of ta-C coating. At first, the reason of thermal degradation was demonstrated by wear rate calculation. The wear rate of ta-C coatings showed an increasing trend with elevated temperature. For investigation of relationship between hardness and graphitization, thick ta-C coatings(2, 3 and $5{\mu}m$) were additionally deposited. As the thickness of ta-C coating was increased, hardness decreased from 58 to 49 GPa, which means that graphitization was accelerated. Therefore, now we are trying to increase $sp^3$ fraction of ta-C coating and control the coating parameters for thermal stability of thick ta-C at high temperatures.

• Journal of the Korean Geotechnical Society
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• v.20 no.3
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• pp.75-83
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• 2004

The Indiana Department of Transportation (INDOT) has permitted the use of Lime Kiln Dust (LKD) as a low-cost construction material in creating a workable platform for soil modification (not for soil stabilization) since the early 1990s on selected projects. However, the enhanced strength of soils with LKD has not been accounted for in the subgrade stability calculations in the design process. This study was initiated to evaluate how the lime kiln dust is a comparable material to hydrated lime. A series of laboratory tests were performed to assess the mechanical benefits of lime kiln dust in combination with various predominant fine grained soils encountered in the State of Indiana, such as A-4, A-6 and A-7-6. In the course of this study, several tests such as the Atterberg limits, standard Proctor, unconfined compression, CBR, volume stability, and resilient modulus were performed. As a result, mixtures of fine grained soils with 5% lime or 5% LKD substantially improve unconfined compressive strength up to 60% - 400%. CBR values for treated soils are in the range of 25 to 70 while those for untreated soils range from 3 to 18. In general, significant increase in resilient moduli of the soils treated with lime and LKD was observed. This indicates that lime kiln dust may be a viable, cost effective alternative to hydrated lime in enhancing the strength of fine grained soils.

• International Journal of Computer Science & Network Security
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• v.22 no.2
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• pp.348-356
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• 2022

The article is devoted to substantiation of theoretical and methodical bases of formation of the organizational-economic mechanism of maintenance of stability of development of region on the bases of influence of potential-forming space in the conditions of formation of creative economy. It was found that the organizational-economic mechanism due to its multifaceted nature does not have a single generally accepted definition, and its acceptable scale and complexity is reflected in the structure, which is very dependent on the scope and conditions of its application, can be very different and contain different elements. In view of this, in order to highlight the characteristics that are inherent in the organizational-economic mechanism of sustainable development of the region on the basis of potential-forming space in the formation of creative economy, the article examines the properties and characteristics of direct organizational and economic mechanism. The necessity of basing the process of formation of any organizational-economic mechanism, including the organizational-economic mechanism of ensuring the sustainability of the region on the basis of the potential-forming space in the conditions of creative economy on the system of principles. In this context, the author's vision is proposed and a set of principles for the formation of organizational-economic mechanism for sustainable development of the region on the basis of the potential of the potential-forming space in the creative economy, as well as revealed the essence of each. According to the structural aspect, the organizational-economic mechanism of ensuring the sustainability of the region's development on the basis of the potential-forming space is proposed to be presented as a set of seven stages, which are implemented in a certain sequence. Within the limits of this research the sequence of realization of the stages making process of formation of the organizational-economic mechanism of maintenance of stability of development of region on the basis of influence of potential-forming space in the conditions of formation of creative economy is defined and their maintenance and essence is presented.

• The Journal of Korean Society for Radiation Therapy
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• v.17 no.2
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• pp.155-160
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• 2005

Purpose : Many authors have been introduced field in field technique and 3-D conformal radiotherapy that increased the tumor dose as well as decreased the dose of abutting critical organ. These technique have multiple beam direction and small beam segments even below 10 MU(monitor unit)for each field. we have confirmed the influence of low MU on dose output and beam stability. Materials and Methods : To study the dose output, the dose for each field was always 90MU, but it divided into different segment size: 1, 2, 3, 5, 10, 15 segments, 90, 45, 30, 18, 9, 6 MU the measurements were carried out for X-ray energy 4 MV, 6 MV, 10 MV of three LINAC(Varian 600C, 2100C, 2100C, 2100C/D), in addition each measurement was randomly repeated three times for each energy. To study the field symmetry and flatness, X-omat V films were irradiated. After being developed, films were scanned and analyzed using densitometer. Results : Influence of low MU on dose is slightly more increase output about $1.2{\sim}2.9%$ in cGy/mu than 90MU, but may not changed beam quality(flatness or symmetry), Output stability depends on dose rate(PRF)rather than beam energy, field size. Conclusion : Presented result are under the limits(out put<3%, flatness<${\pm}3%$, symmetry<2%). The 3 accelerators are safe to use and to perform conformal radiotherapy treatments in small segments, small MU around 10MU. but Even if the result presented here under the limits, continuous adjustments and periodic QA should be done for use of small MU

• Toxicological Research
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• v.20 no.2
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• pp.101-108
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• 2004

The different social reflections about the benefits and the potential risks of genetically modified (GM) crops have evolved with .different reactions in different countries. Many countries including Korea are working toward setting down new guidelines. Korea requires companies to label all food that contains more than 3% GM ingredients. One of the rapid and convenient detection methods of GM ingredients is amplification of the introduced DNAs by polymerase chain reaction (PCR). Many PCR kits for this purpose are commercially available. The objective of this study was to evaluate performance of commercialized GM crop detection kits. The results showed that 6 out of 15 kits tested did not meet the requirements even purposed by the manufacturers themselves in terms of stability, reproducibility, and detection limits, suggesting a potential quality control problem in their design stage or production line. The evaluation also suggests that, although the duplex and triplex detection kits allowed unambiguous detection in a single PCR reaction, the monoplex detection kits were the most sensitive to the detection of GM ingredients. The detection limits also differ between soybean and corn. Results from this study will be useful in the development of sound qualitative tracking systems of GM ingredients for monitoring throughout the cultivation of GM crops, their trans-boundary movement, and food production using GM grains as well as for complying with government guidelines associated with GM crops.

• Journal of Korea Entertainment Industry Association
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• v.13 no.4
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• pp.369-375
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• 2019

This study looked at the effects of teratainment taping and footpad exercise on the improvement of flat foot in a university student. We divided it into flexible flat foot taping group(n=13), flexible flat foot exercise group(n=14), rigid flat foot taping group(n=12), rigid flat foot exercise group(n=13) through a navicular drop test. After one hour's application of teratainment taping and footpad exercise, the height change of navicular, balancing ability and postural stability were evaluated. Change in the height of the navicular was measured before and after intervention, and the balancing ability was measured timed up & go test, and the postural stability ability was evaluated for stability limits in shoulder-width double leg stance, narrow base double leg stance, tandem stance. According to result, there was a statistically significant difference in the left and right foot of the flexible tapping group, right foot of the flexible tapping group, right foot of the rigid tapping group in the change in the height of the navicular in comparison pre- and post- intervention(p<0.5). There were no statistically significant differences in pre- and post- intervention comparisons intragroup and intergroup in balancing ability. There was a statistically significant difference in flexible flat foot exercise group and rigid flat foot taping group in tandem stance in comparison pre- and postintervention in the postural stability(p<0.5). And there was a statistically significant difference in tendem stance of the flexible flat foot exercise group compared to the rigid flat foot exercise group(p<0.5). The results of this study show that teratainment taping and footpad exercise have a significant effect on the improvement of flat foot in adults. Therefore, it is recommended to apply teratainment taping and footpad exercise to improve flat foot.

• 한국연소학회:학술대회논문집
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• 2004.11a
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• pp.79-84
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• 2004

For the non-premixed interacting jet flames, it has been reported that if eight small nozzles are arranged along the circle of 40 $^{\sim}$ 72 times the diameter of single jet, the flames are not extinguished over 2oom/s. In this research, experiments were extended to the partially premixed cases to reduce both flame temperature and NOx emission. Nine nozzles were used- eight was evenly located along the perimeter of the imaginary circle and one at the geometric centre. The space between nozzles, S, the equivalence ratio, ${\Phi}$, the exit velocity and the role of the jet from the centre nozzle were considered. Normally, flame was lifted and flame base was located inside the imaginary circle made by the nozzle. As nozzles went away from each other, blowout velocity increased and then decreased. The maximum blowout velocity diminished with the addition of air to the fuel stream. When the fuel and/or oxidizer were not fed through the centre nozzle, the maximum blowout velocity obtained by varying Sand ${\Phi}$ was around 160m/s. Optimum nozzle separation distance at which peak blowout velocity obtained also decreased with ${\Phi}$ decrease. Flame base became leaner as approaching to the blowout. It seemed that lots of air was supplied to the flame stabilizing region by the entrainment and partially premixing. To approve this idea and to enhance the blowout velocity, fuel was supplied to the centre region. With the small amount of fuel through the centre nozzle, partially premixed flame could be sustained till sonic velocities. It seemed that the stabilizing mechanism in partially premixed interacting flame was different from that of non-premixed case because one was stabilized by the fuel supply through the centre nozzle but the other destabilized.

• Journal of Korean Society of Forest Science
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• v.31 no.1
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• pp.21-29
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• 1976

In foreign countries the national forests began to emerge when the modern body politic came into being and looked upon forests as an indispensible source of national wealth to the effect that eachnation virtually nationalized the forests to promote the public interest such as erosion prevention and water source stability. Most of the forests that are now in national ownership used to be the estates of kings and feudal lords in the Middle Ages. In Korea in national forests come into being toward the end of Yi-dynasty as an outcome of the Japanese colonial policy under which, with the purpose of exploiting the forest resources, the dense forests of large area were systematically transferred into national property to be controlled by establishing the echelon of the national forest stations. The main task of these stations was to fell lumber to no limits.