• Journal of Technologic Dentistry
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• v.39 no.2
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• pp.111-118
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• 2017

Purpose: The study aims to evaluate satisfaction of toothpaste adding natural materials extracted from Zanthoxylum schinifolium and various herbs (Pine, Lemongrass, Spearmint). Methods: We performed the first survey to collect basic data for the development of natural herbal toothpaste. Participants were the general public in Jeonju and Iksan of Jeollabuk-do, and a total of 273 questionnaires were analyzed for the study. By adding anthoxylum schinifolium and herbal extracts (Pine, Lemongrass, Spearmint) to the toothpaste, four kinds of natural herbal toothpaste prototypes were manufactured. The second survey was conducted to assess the satisfaction one week after using the natural herbal toothpaste prototypes. Results: Satisfaction with current toothpaste was 3.52. The most important criterion of toothpaste was the prevention of tooth caries. 55.3% participants obtained toothpaste information through advertising. The survey indicated the most worrisome ingredient of toothpaste was surfactant, showing 55.3%. The overall satisfaction of natural herbal toothpaste was 3.99; among the four natural herbal toothpaste, toothpaste 2 (Zanthoxylum schinifolium, Lemongrass) showed the highest satisfaction as 3.99; and toothpaste 3 (Zanthoxylum schinifolium, Spearmint) showed the lowest satisfaction as 3.56. Conclusion: Four kinds of natural herbal toothpaste showed higher satisfaction as 3.99. In particular, the toothpaste adding Zanthoxylum schinifolium and Lemongrass extracts.

• Food Science of Animal Resources
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• v.36 no.4
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• pp.547-557
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• 2016

This review discusses the status, antimicrobial mechanisms, application, and regulation of natural preservatives in livestock food systems. Conventional preservatives are synthetic chemical substances including nitrates/nitrites, sulfites, sodium benzoate, propyl gallate, and potassium sorbate. The use of artificial preservatives is being reconsidered because of concerns relating to headache, allergies, and cancer. As the demand for biopreservation in food systems has increased, new natural antimicrobial compounds of various origins are being developed, including plant-derived products (polyphenolics, essential oils, plant antimicrobial peptides (pAMPs)), animal-derived products (lysozymes, lactoperoxidase, lactoferrin, ovotransferrin, antimicrobial peptide (AMP), chitosan and others), and microbial metabolites (nisin, natamycin, pullulan, ε-polylysine, organic acid, and others). These natural preservatives act by inhibiting microbial cell walls/membranes, DNA/RNA replication and transcription, protein synthesis, and metabolism. Natural preservatives have been recognized for their safety; however, these substances can influence color, smell, and toxicity in large amounts while being effective as a food preservative. Therefore, to evaluate the safety and toxicity of natural preservatives, various trials including combinations of other substances or different food preservation systems, and capsulation have been performed. Natamycin and nisin are currently the only natural preservatives being regulated, and other natural preservatives will have to be legally regulated before their widespread use.

• Coupled systems mechanics
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• v.9 no.5
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• pp.455-471
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• 2020

This paper presents the results of the study of vertically natural frequency of tractor tires are effected by changing different ground contacts and inflation pressures using the Free Decay Method. The results show that the natural frequencies of the tire are not affected while the vertical acceleration increased strongly due to the increase of inflation pressure when the tire performs free decay vibration on rigid ground. In addition, the number of natural frequency peaks of the tire also increases with increasing tire inflation pressure. On the other hand, the natural frequencies of the tractor tire increases strongly while the vertical acceleration decreases slightly with the increase of tire inflation pressure as the tire performs free decay vibration on soft soil. Further, the natural frequencies of tire-soil system are always higher than that of tire only, and it changed with changing the soil depth. Results also show the natural frequency of tire and tire-soil system is in the range of 3.0 to 10.0 Hz that lie within the most critical natural frequency range of the human body. These findings have to be mentioned and used as design parameters of the tractor suspension system.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2561-2564
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• 2010

The accurate determination of bisphosphonate levels in bone and biological fluids is important in both clinical and pharmacological/toxicological studies; however, the quantitative analysis of the bisphosphonate is difficult because its concentration is quite low in most of biological sample. A novel fluorescent chemosensor (FCS)-based measurement method of bisphosphaonate levels using Naphta-diDPA-$2Zn^{2+}$ (NadDPA-$2Zn^{2+}$, DPA = dipycolylamine), an excellent FCS previously used for detecting PPi, was developed. By the FCS method, the concentration of bisphosphonates having no fluorophores can be determined analyzed with sufficient sensitivity. The results of this study indicate that the FCS-based measurement can be a useful method to analyze bisphosphonates in biological samples.

• Journal of Environmental Policy
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• v.10 no.1
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• pp.151-173
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• 2011

Whenever several natural disasters hit Korea with huge damage of property loss and death toll, government spends huge sums of money for rehabilitation of devastated areas every year. It's time to discuss about a natural disaster insurance, which is a long-term as well as precautionary measure. It is advisable to discuss government involvement through the natural disaster insurance, implementation of countermeasures against natural disasters. The natural disasters insurance have to executed as follows, 1) introducing natural disaster insurance with characteristics of social welfare, which makes fast recovery and anxiety reduction in the low-income bracket. 2) advisable to mix the methods of microinsurance including the natural disaster and index insurance.

• Journal of Electrical Engineering and Technology
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• v.8 no.3
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• pp.524-529
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• 2013

Recently, researchers have become interested in natural ester fluids, as they are an environmentally friendly alternative to mineral oils. Natural ester fluids are a natural resource made from plants; they have higher biodegradability, flash, and fire points, and a greater permittivity compared to conventional mineral oils. However, natural ester fluids also have a higher pour point, viscosity, and water content. These characteristics can hamper circulation and impair the electrical properties of an oil-filled transformer. A large amount of data has been accumulated over the years in regards to mineral insulating oil involving dielectric breakdown voltage and lightning impulse tests. However, natural ester fluids have not had their electrical properties sufficiently characterized. In this paper, we present an investigation into the characteristics of the electrical discharge development in natural ester fluids and in an oil-filled transformer near the pour points. The experiment results show that the electrical properties decreased according to a decrease in the ambient temperature and freezing time. It was found that the pour point and water content of natural ester fluids have a significant effect on the electrical properties.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.11
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• pp.1503-1510
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• 2014

This study organizes scenarios on the power supply plans and electricity load forecasts considering their uncertainties and estimates natural gas quantity for electricity generation, total electricity supply cost and air pollutant emission of each scenario. Also the analysis is performed to check the properness of government's natural gas demand forecast and the possibility of achieving the government's CO2 emission target with the current plan and other scenarios. In result, no scenario satisfies the government's CO2 emission target and the natural gas demand could be doubled to the government's forecast. As under-forecast of natural gas demand has caused the increased natural gas procurement cost, it is required to consider uncertainties of power plant construction plan and electricity demand forecast in forecasting the natural gas demand. In addition, it is found that CO2 emission target could be achieved by enlarging natural gas use and demand-side management without big increase of total costs.

• Proceedings of the Korean Society of Life Science Conference
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• 2006.09a
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• pp.118.1-118.1
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• 2006

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.1
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• pp.100-107
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• 2005

As a result of this study, vitality of natural monuments (large trees) looks relatively good but they require continuous management. Also, the management for condition recovery and condition maintenance, and minimum measures are needed at least to avoid natural calamity. Major points induced are as follows : The first, although most of natural monument large trees showed favorable growth environment, most of them are aged and have dense twigs with requirement for weed trimming to remove complicated and unnecessary branches. In addition, as most of large trees grow alone in a large space with potential natural calamity, thus, minimum measures are required at least. Secondly, change in electric resistance in surveyed large trees was relatively favorable, however, large trees with soil covering showed high electric resistance and were found to have low vitality. As shown, this study was conducted to find out the measurement techniques of natural monuments, Basic foundation is suggested through the measurement of electric resistance, and the vitality of natural monuments; more accurate investigation will be remained for further discussion.

• Hwankyungkyoyuk
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• v.18 no.1 s.26
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• pp.110-119
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• 2005

The aims of this study was to investigate environmental views of national park rangers and their perspectives on natural environment interpretation as managers and to provide a basic resource to make programs regarding natural environment interpretation improve. The specially designed questionnaire was administered to twenty-five national park rangers who had worked at the southern office of Jiri Mountain National Park. Analysis results are as follows. They had have concerns with environmental problems and about preservation of natural environment. Most of them thought that the purpose of natural environment interpretation was to make change regarding public perceptions and attitudes toward natural environment. Over sixty percents of them recognized that publics had rarely participated in the natural environment interpretation program prepared by a national park. It was turned out that public had not concerned with the program because of the lack of their interests and recognitions regarding the natural environment interpretation program due to the lack of active advertisement for it. It is expected that national park rangers need to advertise the necessity of the program and to manage the program effective with more active mind as well as to develop and practice more appropriate programs for natural environment interpretation.