• Journal of Korean Society of Environmental Engineers
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• v.36 no.10
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• pp.691-697
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• 2014

Though the upper stream basin area of Gwanpyung-Cheon in Daejeon, Korea is protected as Green Belt Zone, the stream is under constant environmental pressure due to current agricultural practices and infrastructure development in its basin area. To develop appropriate integrated water resources management plan for the stream, it is necessary to consider not only water quality problems but also water quantity aspect. In this study, Storm Water Management Model (SWMM) was calibrated and validated with sets of field measurements to predict for future water flow and water quality conditions for any rainfall event. While flow modeling results showed good agreement by showing correlation coefficient is greater than 0.9, water quality modeling results showed relatively less accurate levels of agreements with correlation coefficient between 0.67 and 0.87. Hypothetical basin development scenarios were developed to compare effect on stream water quality and quantity when Low Impact Development (LID) technologies are applied in the basin. The results of this study can be used effectively in decision making processes of urban development Gwanpyung-Cheon area by comparing basin management alternatives such as LID methods.

• Restorative Dentistry and Endodontics
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• v.27 no.3
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• pp.249-256
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• 2002

The use of flowable composite resins as liners in class II packable composite restoration has been suggested by some manufacturers. However, the contributions of this technique are unproven. The purpose of this study was to compare the gingival microleakage in class II packable composite restorations with or without the use of flowable composite resins as liners. Slot cavities were prepared on both proximals of 80 extracted human molars and randomly assigned to 8 groups of 20 each. The gingival margins were located at 1mm above CEJ in 80 cavities (group1-4) and 1mm below CEJ in 80 cavities (group5-8). The prepared teeth were mounted in the customized tray with adjacent teeth to simulate clinical conditions and metallic matrix band (Sectional matrix) and wooden wedges were applied. After acid etching and application of Single Bond, each group was restored with the following materials using incremental placement technique: Group 1,5 (Filtek P60), group 2, 3, 4 and group 6, 7, 8 (AeliteFlo, TetricFlow, Revolution/ Filtek P60). All specimens were thermocycled 500 times between 5$^{\circ}C$ and 55$^{\circ}C$ with 1 mimute dwell time, immersed 2% methylene blue dye for 24 hours and then rinsed with tab water. The specimens were embedded in clear resin and sectioned longitudinally through the center of restoration with a low speed diamond saw. Dye penetration at gingival margin was viewed at 20 magnification and analyzed on a scale of 0 to 4. Kruscal-Wallis One way analysis and Mann-Whitney Rank sum test were used to analyze the results. The results of this study were as follows. 1. The leakage values seen at the enamel margin were significantly lower than those seen at the dentin margin(P<0.05). 2. On the enamel margin, packable composite resins with flowable liners showed lower leakage than those without flowable liners, but there were no significant differences among the four groups(P>0.05). 3. On the dentin margin, four groups demonstrated moderate to severe leakage, and there were no significant differences in leakage values(P>0.05).

• Journal of Korean Society of Forest Science
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• v.76 no.1
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• pp.41-50
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• 1987

The various conditions of photographs, especially kinds of films, combinated filters and seasons are important factors for forestry purpose aerial photography. In this paper the variations of tones were compared between color and color infrared, panchromatic black and white and infrared black and white, and among false color photographic images created by using 3 kinds of filters when prints are made. Color infrared film was good for identifying tree species, for its spectral signatures had a greater range of tones and hues than color signatures. In that case taken in May were more effective than taken April. False color photographs were not so good as color photographs because they were mostly dark and indistinct. Infrared black and white film with medium red filter showed potential for separating broad-leaved forests from conifers. MSS composed photographs, when composed with proper bands and densities, were proved useful for distinguishing land use types but not applicable to more detailed practices such as forest type separation and tree species identification.

• Journal of Korea Foundry Society
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• v.11 no.6
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• pp.475-481
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• 1991

In this study the fabrication technology and mechanical properties of AC8A/$Al_2O_3$ Composites by squeeze casting process were investigated to develope for application as the piston materials that require good friction, wear resistance, and thermal stability. AC8A/$Al_2O_3$ composistes without a porosity and the break of preform were fabricated at the melt temperature of $740^{\circ}C$, the preform temperature of $500^{\circ}C$, and mold temperature of $400^{\circ}C$ under the applied pressure of $1200kg/cm^2$ as the results of the observation of microstructures. As the results of this study, the tensile strength of AC8A/$Al_2O_3$ composites was not increased linearly with $Al_2O_3$ volume fraction and so it seemed not to agree with the rule of mixture, which had been used often in metal matrix composite. Also the tensile strength after thermal fatigue test was little different from that before the test. Consequently it was thought that AC8A/$Al_2O_3$ composites fabricated under our experimental conditions had a good thermal stability and subsequently a good interface bonding. Wear rate(i.e., volume loss per unit sliding distance) of AC8A/$Al_2O_3$ composites was decreased with $Al_2O_3$ volume fraction and the sliding speed at both room temperature and $250^{\circ}C$ and so there was a good correlation between wear rate and hardness. Also the wear rate of AC/8A20% $Al_2O_3$ composities was obtained the value of $1.65cm^3/cm$ at sliding speed of 1.14m/sec as compared with about $3.0\;{\times}10^{-8}cm^3/cm$ hyereutectie Al-Si alloy(Al-16%Si-2%Cu-1%Fe-1%Ni), which applied presently for piston materials. The wear behavior of $Al_2O_3$ composites was observed to a type of abrasive wear by the SEM view of wear surface.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.1
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• pp.31-37
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• 2018

Oil/water (O/W) nanoemulsions are effective vehicles to change the permeability of the skin. In this study, we focused on the preparation and characterization of nanoemulsion which serve as colloidal carriers for the dermal application of ceramide IIIB (CIIIB) and stratum corneum (SC) lipids such as cholesterol, and palmitic acid. In order to optimize the nanoemulsions, emulsification process conditions were conducted with regard to droplet size, nanoemulsion stability, and solubility of CIIIB. A decrease in droplet size was observed through emulsification temperature of $80^{\circ}C$ and phase inversion composition (PIC) method. CIIIB has low solubility in oil and water. When the concentration of CIIIB was increased, the droplet size of nanoemulsion was increased. When Lipoid S75-3 was added to the oil phase, the solubility of CIIIB increased, indicating some interactions shown in DSC measurements. CIIIB and SC lipids could be successfully incorporated in nanoemulsions without crystallization or physical instability. In conclusion, a stable nanoemulsion containing the SC lipids could be effective as an efficient moisturizing system for skin.

• Journal of the Ergonomics Society of Korea
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• v.35 no.6
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• pp.569-580
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• 2016

Objective: This study aims to identify the most effective keyboard layout in the area of performance for securing usability in a smart watch-using environment and to verify the usability of touch keyboard calibrated by hand. Background: It is necessary to understand the environmental characteristics in using the smart watch and to secure the usability of touch keyboard based on this understanding in order to take account of the users who use the touch screen in the extreme input conditions caused by the small screen of a smart watch. Method: 30 participants in this study were required to input characters using the QWERTY keyboard and 3x4 keypad (Naratgul, Chunjiin), which were familiar with them, in order to grasp the keyboard layout suitable in the smart watch- using environment; the performance (error rate, performance time) of this case was measured. In addition, 30 participants in this study were required to input the characters setting the QWERTY keyboard with calibrated touch area and the one with uncalibrated touch area, based on the characteristics of touch behavior, by finger typing the keyboard, with the performance (error rate and performance time) of this case measured. Results: QWERTY keyboard (93.3sec) is found to be 31.2% faster than Naratgul keyboard, a kind of 3x4 keypad, and 43.6% faster than Chunjiin keyboard, in the area of efficiency, in the results of the usability evaluation regarding the keyboard layout. QWERTY keyboard with calibrated touch area (7.5%) is found to be 23.5% improved compared to the QWERTY keyboard with uncalibrated touch area (9.8%) in the area of accuracy (error rate). The results of the usability evaluation regarding the QWERTY keyboard with touch area calibrated by finger typing the keyboard and QWERTY keyboard with calibrated touch area (80.7sec) is found to be 5.7% improved compared to QWERTY keyboard with uncalibrated touch area (85.6sec) in the area of efficiency (performance time). Conclusion: QWERTY keyboard is found to have an effective layout in the area of efficiency in the smart watch-using environment, and its improved usability is verified in the areas of accuracy and efficiency in the QWERTY keyboard with a touch area calibrated by finger typing the keyboard. Application: The results of this study may be used to set up the basic touch keyboard of the smart watch. The input usability is expected to secure the smart watch-using environment, which is an extreme input condition by applying QWERTY keyboard with touch area calibrated by finger typing the keyboard.

• Korean Business Review
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• v.19 no.2
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• pp.231-259
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• 2006

Performance-based budgeting(hereafter PB2) is supposed to improve efficiency and effectiveness of public organizations. Governmental PB2 is based on output flow rather than input flow. Since 1990s, many OECD nations including New Zealand and the United States have been changing their budget system to PB2. The Korean Government has been using input-based budgeting focusing on the size of expenditures. In 1999, The Ministry of Planning and Budget(hereafter MPB) conducted pilot projects for divisions or agencies of governmental departments for the purpose of improving efficiency in expenditure, rationalizing budget allotments, and inducing budget savings. However, performance budgeting may also have problems in terms of measurement and application. Due to the fact that public goals are abstract and may vary, it is difficult to induce performance indicators from public goals. There also seem not to be any performance indicators which correspond with the conditions of desirable indicators, such as validity, reliability, clarity, practicality, controllability and so on. In terms of applying an original budgeting plan, the difficulty of linking performance and budgeting, the appearance of unintended negative effect and externalities, and the repulsion of subordinated agencies are expected. Now days, local government is going to introduce PB2. Same problem may happen in the local government. And Therefore, the objectives of this paper are to introduce PB2 onlocal government and review a alternative strategy with the purpose of smoothly settling performance budgeting on local government. That is the linkage of Balanced Scorecard(BSC) and PB2.

• Korean Business Review
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• v.11
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• pp.415-437
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• 1998

On choosing insurance terms it would be a reasonable choice to choose insurance terms in proportion to how much risk is to be with considering of how much risk is exactly to be in a cargo's owner of his or hers as there are conditions such as a character of cargo, a packing condition, a loading ship, a shipping section, and a premium. But when we see on the present state of the statistical insurance table, the effects are entirely different from it stated above and these serious problems are of both the problem to prove who is on duty and the problem to cover how much the indemnity are to be. When we see a shipper as the insured, in the last 3 years that all risks has been more than 95 percent is to prove the reason mentioned above and there would be an intention for the shipper to transfer a claim for the indemnity to the insurer to evade from the complexity. Also when we see how much both I.C.C and New I.C.C is used, New I.C.C has been used less two times than I.C.C, that is due to the restriction of the scale of covering the indemnity. So both the introduction of trade clause as to insured in the same line of business and the positive application, taking into account of the principle of proving who is on duty and the scale of covering the indemnity, are to be accomplished.

• Journal of the Korean Institute of Telematics and Electronics
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• v.16 no.4
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• pp.36-46
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• 1979

Using N_ Ch silicon gate technology . the capacitors and transistors with various dimenssion were fabricated. Although the applied process was somewhat standard the conditions of ion implantation for the gate were varied by changing the implant energies from 30keV to 60keV for B and from 100 keV to 175keV for P . The doses of the implant also changed from 3 $\times$ 10 /$\textrm{cm}^2$ to 5 $\times$ 10 /$\textrm{cm}^2$ for B and from 4$\times$ 10 /$\textrm{cm}^2$ to 7 $\times$ 10 /$\textrm{cm}^2$ for P . The D. C. parameters such as threshold voltage. substrate doping level, the degree of inversion, capacitance. flat band voltage, depletion layer width, gate oxide thickless, surface states, motile charge density, electron mobility. leakage current were evaluated and also compared with the corresponing theoretical values and / or good numbers for application. The threshold voltages measured using curve tracer and C-V plot gave good agreements with the values calculated from SUPREM II which has been developed by Stanford University process group. The threshold vol tapes with back gate bias were used to calculate the change of the substrate doping level. The measured subthreshold slope enabled the prediction of the degree of inversion The D. C. testing results suggest the realized capacitors and transistors are suited for the memory applications.

• Journal of the Korea Convergence Society
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• v.9 no.2
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• pp.359-369
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• 2018

This study tried to illustrate the process of the experiences of university student athletes in campus who are engaged in study and sports. it is aimed to interpret and describe the everyday life of athlete students, and establishing a desirable human talent and to set the right necessary direction for the education of athlete students. For this, it selected 10 research participants as student athletes in J University located in Chungcheongnam-do and collected data through an in-depth interview. As for the data analysis, concepts were derived according to the grounded theory analysis method suggested by [10] and the research results composing the coding paradigm to clarify the relations between concepts are as following. First, 120 concepts, 17 subcategories, and 10 upper categories were deducted in the open coding. Second, the contextual factors of the campus life motive were "participation in sports" and "participation in study" and the central phenomena were regarded as "the significance of campus life in which study and sports run parallel. The conditions of arbitration were summarized as 'formation of my relations" and "ability improvement" in sports and study, and the operation/interaction strategy were categorized as "importance of study" and "negative thinking." As for the last result, "reflecting campus life", "my own identity", and "planning future" were categorized, and it is judged that the application of the policy to improve the ability of student athletes that comprehend all study and sports.