• Journal of Technologic Dentistry
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• v.37 no.2
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• pp.63-67
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• 2015

Purpose: This study, it was observed on the effect of material and thickness of the mouth guard on postural balance in order to assess the influence of the use of a mouth guard. Methods: The mouth guards of 10 adults selected as the experiment subject was sorted into each of hard and soft material, and these were made as thickness of 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm by each of the material. Results: The results of this study are expected to wear the mouthguard hard to influence positive influence on the improvement of the muscle strength, static balance. Conclusion: Suggest the need for additional research on dynamic balance.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.144-144
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• 2000

Air balance hoists are widely used in handling of heavy materials in industry. Currently used air balance hoists adopt manual switches for vertical motion, thus the operator has a difficulty in operating of the switches and handling of material simultaneously. To overcome this difficulty, this study develops a weightless air-balance-hoist system using compressed air. This system memorizes the weight of material in terms of pneumatic pressure with a pneumatic circuit. Such memory of the material weight is used for achieving weightless handling of materials. Through a series of experiments, handling forces and the response of the system for various material weights are analyzed. The results show that the developed system can be used for weightless handling o( heavy materials.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.833-843
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• 1998

It is noted that the red tides and the oxygen-deficient water mass are extensively developed in Masan Bay during summer. The nutrients mass balance was calculated in Masan Bay, using the three-dimensional numerical hydrodynamic model and the material cycle model. The material cycle model was calibrated with the data obtained on the field of the study area in June 1993. The nutrients mass balance calculated by the combination of the residual currents and material cycle model results showed nutrients of surface and middle levels to be transported from the inner part to the outer part of Masan Bay, and nutrients of bottom level to be transported from outer part to inner part of Masan Bay. The uptake rate of DIN in the box A1(surface level of inner part) was found to be 337. 5mg/$m^3$ㆍday, the largest value in all 9 boxes and that of DIP was found to be 18.6mg/$m^3$ㆍday in box A1, and the regeneration rate of DIN was found to be 78.2mg/$m^3$ㆍday in the box A3(bottom level of inner part), and that of DIP was found to be 18.6mg/$m^3$ㆍday in box A1. The regenerations of DIN and DIP in the water column of the entire Bay were found to be 7.66ton/day and 760kg/day, respectively. And the releases of DIN and DIP from the sediments of the entire Bay were found to be 2.86ton/day and 634kg/day, respectively. The regeneration rate was 2.5 times as high as the release rate in DIN, and 1.2 times in DIP. The results of mass balance calculation showed not only the nutrients released from the sediments but the nutrients regenerated in water column to be important in the control and management of water quality in Masan Bay.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.4
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• pp.61-68
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• 2008

Of the seven base units of the international system of units, only the kilogram is still defined in terms of a material artifact. One of the experimental approaches opening the way to a new definition of the kilogram is the watt balance To improve the performance of the NPL watt balance, we need to quantify and reduce hysteresis effects in the balance knives. In this paper, we discuss the mechanical characteristics of the knife edges used in the NPL watt balance. The hysteresis mechanism is analyzed using the finite element method. It is found that the cause of hysteresis is not normal stress but shear, and the deformation of the flat, rather than the knife, is an important factor in the hysteresis mechanism. The study presented here, using finite element analysis, suggests that parameters such as material property, tip radius and knife straightness can be more important than others, such as friction coefficient, tip angle, etc.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.1
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• pp.7-12
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• 2012

Chemical mechanical polishing(CMP) technology is faced with the challenge of processing new electronic materials. This paper focuses on the balance between chemical and mechanical reactions in the CMP process that is required to cope with a variety of electronic materials. The material properties were classified into the following categories: easy to abrade(ETA), difficult to abrade(DTA), easy to react(ETR) and difficult to react(DTR). The chemical and mechanical balance for the representative ETA-ETR, DTA-ETR, ETA-DTR and DTA-DTR materials was considered for defect-free surfaces. This paper suggests the suitable polishing methods and examples for each electronic material.

• Journal of Korea Foundry Society
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• v.15 no.5
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• pp.477-482
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• 1995

A computer simulation model of various smelting process for melting waste sand was developed by using energy and material balance concept. This model can predict the coal, flux and oxygen consumption and the volume and temperature of off-gas. The major critical variables for smelting process can be explained by using the analysis of energy and material balance. The major conclusions were as follows; 1. The most important variables for smelting process were high post-combustion ratio, high heat transfer efficiency and refractory protection technology. 2. For saving energy in this smelting process, selection of raw materials i.e coal, flux are very important, espacially using of low volatile coal is very profitable. 3. The treatment cost of waste sand is high and environmental restriction is severe, in this reason we must be concerned in the treatment of waste sand by smelting process.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.1447-1448
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• 2004

As the plants are classified as a bulk facility by the Agency's safeguards criteria, the Material Balance Evaluation is a good tool to timely detect diversion that will be accomplished through the creation of defects as small as bias defects. Through all evaluations made by the Agency, it Is strongly recommended to report SRD based on both weight and enrichment, maintain the reliable MUF declaration and improve the gamma spectrometry measurement procedure. These recommendations have been now applied and are going on.

• Environmental and Resource Economics Review
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• v.23 no.3
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• pp.365-408
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• 2014

The purpose of this paper is to compare efficiencies, two stage efficiencies, and the reduction of economic growth due to the restraint of $CO_2$ and fossil fuel in two efficiency approach by pointing out the limit of traditional efficiency approach and introducing material balance approach. The efficiencies under the traditional approach and the material balance approach report significant gaps when they are analyzed in detail. Especially, in case not including fossil fuels, the low income countries show the bad performance of production efficiencies, but OECD and high-middle income countries reveal the better performance than that of the low countries. It fails to reflect the reality justly. Based on the material balance approach, the low income countries report the higher performance and the alleviated effect of environmental components for economic growth than OECD's.

• Korean Journal of Pharmacognosy
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• v.46 no.3
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• pp.223-228
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• 2015

This mass balance study about ginsenoside Rg1 and Re in Red ginseng processed from Fresh ginseng is useful to understand that herbal material sources of ginseng and raw material consumption in Red ginseng preparations. In our results, total molar amounts of ginsenoside Rg1, Re and their converts in Fresh ginseng, Red ginseng, and Red ginseng extract are substantially the same. The molar amounts of ginsenoside Rg1, Re (4.324, 2.880 μmol/g) as starting materials in Fresh ginseng are kept constant as total molar amounts (sum of starting and converts) in Red ginseng (4.264, 2.596 μmol/g) and Red ginseng extract (3.389, 3.129 μmol/g). This result means that protopanaxtriol type ginsenosides and their characteristic converts are not destroyed or inflowing in Red ginseng process. Therefore, it is important for quality assurance of Red ginseng preparations that the ratio between ginsenosides Rg1, Re and these converts is kept constant.

• 한국연소학회:학술대회논문집
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• 2013.06a
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• pp.51-54
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• 2013

Rotary kiln reactors are frequently equipped with an axial burner with which solid burden material is directly heated. Lifters are commonly used along the length of the system to lift particulate solids and increase the heat transfer between the solid bed and the combustion gas. The material cascading from the lifters undergoes drying and reacting through direct contact with the gas stream. In this study, volume distribution of materials held within lifters was modeled according to the different lifter configuration and appropriate configuration was used for the design purpose. This was applied to the one-dimensional heat balance model of a counter-current flow reactor, which contributes to the increase of the effective contact surface, and thereby enhances the heat transfer.