• Fire Science and Engineering
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• v.26 no.6
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• pp.1-6
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• 2012

There are specific indications about additional gas for the unencloseable openings of the carbon dioxide extinguishing systems. But there are no indications for other gas extinguishing systems including clean agent extinguishing systems only have the principle when it need, apply it. Therefore, this study suggested applying the equation of additional gas for the unencloseable openings of the carbon dioxide to all of the other fire suppression gas that we are use.

• International Journal of Clinical Preventive Dentistry
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• v.14 no.4
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• pp.247-255
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• 2018

Objective: Osseointegration is essential process for successful implants and effects to implant in long term, therefore, passive fitness of good prosthesis is necessary. To make a good prosthesis, at first it should be done a sectioned casting and then joined method of sectioned casting body is recommended. Methods: In this study, to provide the fundamental data on stable connection method for successful implants, the author tested fitness of casting body, and compared difference between gas soldering technique and laser welding technique. Results: In fitness test of 2 abutment (test A, C), gas soldering group's fitness in the opposite part of connection was worse than laser welding group. In fitness test of 3 abutment (test B, D), gap distance was increased both in gas soldering technique and laser welding technique. Gap distance at the connecting part and the opposite part of the abutment in gas soldering technique was worse than laser welding technique and the more additional abutment, the worse gap distance in gas soldering technique. In fitness test of 3 abutment (test B, D), there's little variation in No. 2 abutment when connecting soldering process was done and there's little influence on already soldered connection part when the additional soldering connection was done. Conclusion: On weak loading condition and the part which is needed an accuracy, laser welding technique is more effective and on long-span prosthesis and frequent chewing loading part, laser welding technique is recommended first and applying additional gas soldering technique would be better for making much more successful prosthesis.

• Metals and materials international
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• v.24 no.6
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• pp.1422-1431
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• 2018

We investigated the additional (secondary) cooling effect of casted strips on the magnetic properties of Nd-Fe-B sintered magnets. The Nd-Fe-B sintered magnets were fabricated with the casted strips prepared without and with additional cooling. Additional cooling was achieved by blowing Ar gas at various pressures (0.1, 0.3, and 0.6 MPa) on the free-side surface of the strips during the strip-casting process. The higher magnetic properties of $H_c$, $B_r$, and $(BH)_{max}$ of the final Nd-Fe-B sintered magnets were obtained for 0.1 MPa rather than for 0.0 MPa. The best microstructure of the columnar grains in the casted strips was produced with the aid of a lower pressure of gas on the free-side surface. It was found that the microstructure of the strips affects the distribution of grains grown in the sintered magnets. This report demonstrates that the improved magnetic performance of Nd-Fe-B sintered magnets was achieved via additional gas cooling.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.6
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• pp.95-101
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• 2002

There are many effective parameters to high concentration ozone generation. These parameters became very important elements should be considered before designing ozone generator. After designing, there are many peripheral parameters to greatly affect to high concentration ozone generation also. In this study, of many effective peripheral parameters on high concentration ozone generation, the effects of flow rate of inlet oxygen gas and some kinds of additional gases on ozone concentration were investigated As a result, when inlet oxygen gas was introduced at the range of 0.75［LPM］～2.00［LPM］ the highest ozone concentration of 71145［ppm］ was obtained at 1.25［LPM］. When the additional nitrogen gas was mixed to oxygen gas at the range of 0.0［vol%]～6.4［vol%］ the highest ozone concentration of 73135［ppm］ was obtained at 0.8［vol%］ of nitrogen gas. This showed 3［%］ increasing compared to the case of pure oxygen gas inlet. When the additional argon gas was mixed to oxygen gas at the range of 0.0［vol%］～6.4［vol%］ the highest concentration of 67288［ppm］was obtained at 0.8［vol%］of argon gas. This is decreased value compared to that of introducing the pure oxygen.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.2
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• pp.349-362
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• 1996

To determine the factors to affect on stone surface porosities produced from hydrogen gas of additional silicone, both putty and syringe type of 7 commercially different additional silicone impression materials(Blend-A-Scon, Correct VPS, Exaflex, Express, Extrude, Provil, Reprosil) were chosen and NewFujirock(GC) was poured into the impressions of detail-reproducing test block at 1, 15, 30, 45, 60 minutes after the impression materials had set and 4 specimens were made for each pouring time, each type of impression material, and each consisency and So, 280 specimens were made in total. The number of surface porosities of same area($2826 mm^2$) which were typically caused by hydrogen gas using the stereoscope(X 7.5) by two observers. Comparison of putty-syringe type and among the impression materials are tested by Kruscal-Wallis method and Mann-Whitney method(p<0.05). The results are as follows. 1. The number of porosities decreased as the pouring time of stone was delayed on both putty and syringe type of additional silicone materials. 2. The putty type significantly produced more porosities than syringe type except for the group of Reprosil.(p<0.05). 3. In case of putty type, the number of porosities increased as following order. Reprosil / Blend-A-Scon and Provil / Correct VPS and Extrude / Express and Exaflex. 4. In case of syringe type, Blend-A-Scon and Extrude produced no porosity and Exaflex and Provil at 30 minites, but Express produced porosities even at 60 minutes and the most. Additional silicone impression material releases hydrogen gas, and that fact can make the resulting die stone model useless. So, to minimize these adverse effects, it is desirable not to expose putty type of additional silicone on critical impression surface because putty type has a tendency to produce more porosities than syringe type. And it is important to have sufficient time before pouring the stone on impression because porosities produce less as time passes after setting of impression material. Also, there are differences among 7 additional silicone impression materials, so it is desirable to choose adequate brand of additional silicone for good laboratory work.

• KIEAE Journal
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• v.14 no.5
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• pp.21-28
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• 2014

To improve environmental problem as globally climate changes, domestic and foreign government have been trying to reduce green gas emitted by all industries. With making the green building certification system that assess the substantiality and energy performance of building, a governments have been using by a way for reducing green gas emitted in building industry. G-SEED(Green Standard for Energy & Environmental Design) developed in Korea have been reinforcing, and a number of projects certifying the G-SEED have been increasing continuously. As a demand of G-SEED certification is rising, a question on the additional cost data as certifying G-SEED is rising. It is because additional cost as getting the certification is important fact for G-SEED level decision and whether getting the certification or not. Therefore, this study analyzed additional construction cost as certifying G-SEED through performance improvement and design change of general office building not to get G-SEED. In conclusion, an additional construction cost ratio of G-SEED projects to the reference building is drawn as certified level; +0.26%, silver level; +2.29%, gold level; +3.89%, and platinum level; +5.48%.

• International Journal of Highway Engineering
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• v.18 no.1
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• pp.119-129
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• 2016

PURPOSES : The purpose of this study is to develop a methodology for estimating additional carbon emissions due to freeway incidents. METHODS : As our country grows, our highway policy has mainly neglected the environmental and social sectors. However, with the formation of a national green growth keynote and an increase in the number of people interested in environmental and social issues, problems related to social issues, such as traffic accidents and congestion, and environmental issues, such as the impact of air pollution caused by exhaust gases that are emitted from highway vehicles, are beginning to be discussed. Accordingly, studies have been conducted on a variety of environmental aspects in the field of road transport, and for the quantitative calculation of greenhouse gas emissions, using various methods. However, in order to observe the effects of carbon emissions, microscopic simulations must use many difficult variables such as cost, analysis time, and ease of analysis process. In this study, additional greenhouse gas emissions that occur because of highway traffic accidents were classified by type (incident handling time, number of lanes blocked, freeway level of service), and the annual additional emissions based on incidents were calculated. According to the results, congestion length and emissions tend to increase with an increase in incident clearance time, number of occupied lanes, and worsening level of service. Using this data, we analyzed accident data on the Gyeong-bu Expressway (Yang-Jae IC - Osan IC) for a year. RESULTS : Additional greenhouse gas emissions that occur because of highway traffic accidents were classified by type (incident handling time, number of lanes blocked, freeway level of service) and annual additional emissions caused by accidents were calculated. CONCLUSIONS : In this study, a methodology for estimating carbon emissions due to freeway incidents was developed that incorporates macroscopic flow models. The results of the study are organized in the form of a look-Up table that calculates carbon emissions rather easily.

• Proceedings of the KWS Conference
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• 2010.05a
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• pp.26-26
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• 2010

EGW process has been applied to joining of ship block with vertical-up position at high production rate. The workability of EGW, however, has been interrupted by too much slag production. Two electrodes EGW showed more severe workability than that of one electrode EGW. Therefore, to understand the effect of discharge amount of EGW slag on workability and mechanical properties, two different slag discharge amount have been controlled at the same welding conditions. The results are as follows; 1) Workability has been improved by any additional slag discharge. 2) Mechanical properties have been deteriorated with any additional slag discharge. 3) Chemical compositions of weld metal have been changed by any additional slag discharge.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.4
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• pp.129-136
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• 2017

Climate change is the biggest environmental issue of our times. A variety of activities to reduce greenhouse gas emissions have been in progress to observe the Kyoto Protocol. Especially, the Energy Target Scheme is created to reduce greenhouse emission with the supervision of Korean government. This includes Green-house Gas Information Systems to promote activities in the private sector to reduce green-house gas emissions, to cut a cost of energy use, and to reduce GHG emissions. Also, the system has calculated the amount of greenhouse gases. Without any additional investment, 2.75% savings are increased over the previous year. In service sector, a cooperation of customers and employees is necessary. A reduction of GHG emissions requires a proper service organization, considering an amount of investment and payback period. Without any additional investment or replacement, employees can save energy easily turning off ventilation systems an hour before employees' departure, installing timers to turn off water purifiers and vending machines after some period of no use. The Green-house Gas Information System is similar to that of Environmental Management System. However, the Excel is the best program to calculate an amount of green-house gas emissions, and to assess for a reduced amount of GHG emissions. A goal of this research is to propose a practical method in the private sector to calculate an amount of green-house gases. The Green-house gas Information System based on Excel spreadsheet gives standards for good evaluation. The greenhouse gas information system establishes and executes the policies and objectives related to greenhouse gas emissions Similar to ISO 14001 environment management system structures, the advantages of using simplified Excel Sheet for calculating GHG emissions and reducing GHG emissions are easy to access.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.73-73
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• 2003

We report here the results on N-acetyl-N'-methylamide of alanine (Ac-Ala-NHMe) calculated using the ab initio molecular orbital method with the self-consistent reaction field (SCRF) theory at the HF level with the 6-3l+G(d) basis set to investigate the conformational preference of alanine depending on the backbone torsion angles $\square$ and$\square$ in the gas phase, chloroform, and water. There are seven local minima (LM) in the gas phase and two additional LM are found in chloroform and water. These two additional LM A (an $\square$-helical structure) and F (a polyproline structure) are stabilized only in solutions. In the gas phase, the lowest LM is the conformation C with a C$\sub$7/ intramolecular hydrogen bond and the relative conformational energies range from 0.3 to 6.0 ㎉/mol. In chloroform, the lowest LM is the conformation E (an extended structure) and the relative conformational energies range from 0.7 to 4.9 ㎉/mol. In particular, we identified 14 possible transition states connecting between seven LM in the gas phase. The search for transition states probable in chloroform and water is now in progress.