• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.11a
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• pp.13-16
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• 2008

This paper is to present the performance data for improved direct setting method using tile bond for application of porcelain tile under 1 percent absorptance. For this purpose, improved direct setting method type 1 & 2(tile bond curing time 0, 24H) were compared with the conventional setting methods(including direct setting method and improved pressure setting method) in the sight of the adhesive stability of porcelain tile. It tested for tiles after 14, 28days under standard condition and severe conditions. The severe conditions were water immersion, heat ageing(70℃) and freeze-thaw cycle. On the basis of test results, the adhesive strength of direct setting method was lowest for the conventional setting methods. But improved direct setting method using tile bonds(A, B) came close to the result of improved pressure setting method using tile bonds.

• Journal of Microbiology
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• v.37 no.4
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• pp.263-266
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• 1999

In examining bacterial growth on glass surfaces immersed in sea water, we found serious differences between enumeration methods. Therefore, we compared various methods and found sonication and direct count methods were superior to other methods. Since the direct count method was not suitable for long-term investigation, we chose the sonication method and confirmed that sonication periods 8 times for 30 seconds was optimal for the detachment of bacteria from glass surfaces.

• Journal of Korean Society of Steel Construction
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• v.22 no.4
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• pp.293-303
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• 2010

The purpose of this study was to evaluate the influence of the methods of application of the direct analysis method, using the load amplification factor suggested by the KBC 2009 design code, for the evaluation of frame stability. For this purpose, the direct analysis method was performed for three-story-one-bay and five-story-three-bay unbraced steel frames with various notional loads, bending stiffness reductions, and factor B2s. The results of the analyses were compared with the results of the second-order inelastic analysis to evaluate the influence of the applied methods. The scale of the frame, the axial load ratio, and the axial load distribution pattern were added to the main parameters to investigate the external effects. The research results showed that the influence of the methods of application of the direct analysis method is not significant in the case of the required axial strength and the application of the additional notional loads; and that the application of the factor B2 with the story stiffness concept to the direct analysis method is appropriate for the required flexural strength.

• The korean journal of orthodontics
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• v.41 no.6
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• pp.447-453
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• 2011

Objective: We compared the shear bond strength (SBS) of lingual retainers bonded to bovine enamel with three different resins using direct and indirect methods. Methods: Both ends of pre-fabricated twisted ligature wires were bonded to bovine enamel surfaces using Light-Core, Tetric N-Flow, or Transbond XT. Phosphoric acid-etched enamel surfaces were primed with One-Step prior to bonding with Light-Core or Tetric N-Flow. Transbond XT primer was used prior to bonding with Transbond XT. After 24 hours in water at $37^{\circ}C$, we performed SBS tests on the samples. We also assigned adhesive remnant index (ARI) scores after debonding and predicted the clinical performance of materials and bonding techniques from Weibull analyses. Results: Direct bonding produced significantly higher SBS values than indirect bonding for all materials. The SBS for Light-Core was significantly higher than that for Tetric N-Flow, and there was no significant difference between the direct bonding SBS of Transbond XT and that of Light-Core. Weibull analysis indicated Light-Core performed better than other indirectly bonded resins. Conclusions: When the SBS of a wire retainer is of primary concern, direct bonding methods are superior to indirect bonding methods. Light-Core may perform better than Transbond XT or Tetric N-Flow when bonded indirectly.

• Nuclear Engineering and Technology
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• v.26 no.2
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• pp.205-211
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• 1994

The best method is selected among the 3 digital dynamic compensation methods which are developed or applied for the Rhodium self-powered neutron detector. The three digital dynamic compensation methods are the existing Dominant Pol Tustin method of the COLSS(Core Operating Limit Supervisory System), the Direct Inversion method and Kalman Filter method. The Direct Inversion method is an improved method of D. Hoppe and R. Maletti and the Kalman Filter method is developed using the Kalman Filter. Response times of the compensated signals to achieve 90% of a step input are 28.1, 17.2 and 6.5 seconds respectively for the same noise gain telling that the Kalman Filter method is the best amens the 3 methods.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.256-266
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• 1993

History , achievement and future of direct-wet-rice-seeding technique in Korea and problems encountered in on-farming research were introduced. Some farmers are very eager to lower production cost and save labor. Their effort results in several direct-wet-seeding methods and seeding machines. The design problems and improvement points related to the direct -wet-rice-seeding machines were drawn out of field test.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.23 no.1
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• pp.77-88
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• 2005

Direct Georeferencing (DG) is based on the direct measurement of the projection centers and rotation angle of sensor through loading the GPS and INS in aircraft. The methods can offer us to acquire the exterior orientation parameters with only minimum GCPs, even the ground control process could be completely skipped. In this study, a CCD camera is simultaneously used in GPS/INS, and acquired CCD image through Direct Georeferencing produce digital orthoimage. In this process, methods of combining sensor and digital orthoimage are examined and estimated. For the comparison of the positioning accuracy digital orthoimage through Direct Georeferencing, GCPs determined by GPS surveying are used. Two digital orthoimage are produced; one with a few GCP and the other without them. The produced maps can be used to correct or revised 1:1,000 or 1:5,000 scale maps accordingly.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.84-88
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• 2001

Two methods of nitrogen application at the 4th leaf stage were evaluated in direct-seeding rice cultivation on dry paddy soil: one was the top dressing of nitrogen on dry paddy condition before irrigation (TNDP) for labor saving, and the other was the top dressing of nitrogen on dry paddy with mechanical rotavation of the inter-row space (TNDPIR) for increasing the efficiency of nitrogen. To evaluate these two application methods, leaf chlorophyll contents, growth characteristics and yields were compared with two conventional methods, basal application (BA) and top dressing on flooded paddy condition at the 4th leaf stage (TNFP). The SPAD value of rice in TNDP was similar with that in TNFP throughout the whole growth stage of rice. Also, there were no differences in rice growth and yield between the two methods. However, in TNDPIR, the SPAD value was the highest during tillering stage among the four application methods, and the tiller number, LAI at heading stage and the panicle number were higher than the two conventional methods.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1992.08a
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• pp.146-149
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• 1992

The dynamic inelastic analysis is now often performed for the safe structural design against the seismic events or explosions. Several powerful methods of dynamic inelastic analysis such as direct intergration methods and modal superposition methods were developed with the development of computers during the last three decades. This type of analysis generally adopts the step-by-step time-integration procedure and gives a complete time history of the evolution of the structure.(omitted)

• Structural Engineering and Mechanics
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• v.27 no.6
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• pp.741-771
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• 2007

Tests were conducted on two partially pre-stressed concrete solid beams subjected to combined loading of bending, shear and torsion. The beams were designed using the Direct Design Method which is based on the Lower Bound Theorem of the Theory of Plasticity. Both beams were of $300{\times}300mm$ cross-section and 3.8 m length. The two main variables studied were the ratio of the maximum shear stress due to the twisting moment, to the shear stress arising from the shear force, which was varied between 0.69 and 3.04, and the ratio of the maximum twisting moment to the maximum bending moment which was varied between 0.26 and 1.19. The required reinforcement from the Direct Design Method was compared with requirements from the ACI and the BSI codes. It was found that, in the case of bending dominance, the required longitudinal reinforcements from all methods were close to each other while the BSI required much larger transverse reinforcement. In the case of torsion dominance, the BSI method required much larger longitudinal and transverse reinforcement than the both the ACI and the DDM methods. The difference in the transverse reinforcement is more pronounce. Experimental investigation showed good agreement between design and experimental failure loads of the beams designed using the Direct Design Method. Both beams failed within an acceptable range of the design loads and underwent ductile behaviour up to failure. The results indicate that the Direct Design Method can be successfully used to design partially prestressed concrete solid beams which cater for the combined effect of bending, shear and torsion loads.