• International Journal of Highway Engineering
• /
• v.11 no.4
• /
• pp.133-142
• /
• 2009

This research is performed to estimate quality of trial pavement for construction and analyze effect of fatigue life by using the pay factor. Specially, asphalt content which is difficult to control the pavement quality, is selected by pay adjustment standard factors and pay factor is calculated by asphalt content. This research is also analyzed to present relation of fatigue life according to asphalt content, to evaluate quality of the road pavement by calculating pay factor of sampling trial field mixture 2 times. This research confirms that it is different quality of road pavement according to pay factor changes. To analyze the fatigue life of pavement by using asphalt mixture for trial field. As a result, it is conformed that high pay factor could be high fatigue life of trial field. This means that pay factor using probability theory reflects road pavement fatigue life. Also, this study is included that beam fatigue test manufacturing specimen such as mixing type of plant which purvey asphalt mixture to trial field, compared with fatigue life of trial field. As a result, the fatigue life of specimen that is manufactured by mix type is higher than trial field specimen. This means that performance of road pavement can be reduced by gradation or other effects. Therefore, to exactly evaluate the quality of road pavement, pay factor should be calculated appling various pay adjustment standard factors such as gradation, air-void in U.S. states which is adopted pay adjustment.

• Journal of Advanced Marine Engineering and Technology
• /
• v.15 no.5
• /
• pp.47-54
• /
• 1991

The lip seals widely used nowadays in stern tube sealing system of ships have radial sealing contact with shafts or liners, on the other hand the face seals of stern tube sealing system have axial sealing contact with seat. Because of axial sealing contact, the face seals have a large number of merits such as durability of life, simplicity of structure, easy fitting and replacement, etc. In this paper, for the purpose of development of face seals, the fundamental properties of axial sealing contact were analyzed and a trial face seal was designed and manufactured using N.B.R. rubber and Thordon which is widely used for bearing materials. The seal proper of trial face seal was made from N.B.R. rubber and the face insert was made from Thordon, thermosetting resins which are three dimensional, cross linked condensation polylmers. The performance test of trial face seal was carried out on the test bench which was specially designed and manufactured. The results were satisfactory enough to be used in practical stern tube sealing system.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1996.04a
• /
• pp.398-401
• /
• 1996

It is the aim of this study to introduce the application method for the new estimation system of deterioration caused performance decrement of exterior wall by infrared theromography. With this help of this trial test, the defect such as void and honeycomb of esveria wall can be shown easily. Espicially by selecting the weathering condition, it becomes easier to identify defect than with original image. It was confirmed that this trial monitoring system is very useful to identify the defect of exterior wall.

• Proceedings of the Optical Society of Korea Conference
• /
• 2008.07a
• /
• pp.421-422
• /
• 2008

In this paper, we will present the results of 1Gbps x 16 channels RSOA remodulation based WMD-PON field trial test. We have confirmed the system reliability, also verified the system could reliably deliver the service such as internet, VoD through the system during the field trial test.

• Journal of Navigation and Port Research
• /
• v.38 no.6
• /
• pp.593-600
• /
• 2014

Information supporting system which is based on real-time prediction of currents to be applicable to the sea trial test of ship is developed. In the system, the spatial distribution of currents at specific time and the trends of variability of currents occurring at specific sites are also given as valuable information for sea trial test of ship. In addition, the system has a capability to connect with a GPS which provides information including speed loss of the ship caused by currents on the way of voyage. With information from the sea trial test, the system is also capable of delivering optimum time and pathways by considering calculated speed loss of ship at specific time and its pathway. Having information described as above, the real-time current prediction system supports and provides functions of not only running the test in an efficient way but also providing valuable information which is encouraged to be used during the test by installing at the ship.

• Journal of Advanced Marine Engineering and Technology
• /
• v.36 no.5
• /
• pp.627-634
• /
• 2012

This study includes results of basin test for hydrodynamic performance evaluation with a developed inflatable kayak. Inclining experiment and turning trial experiment of the developed inflatable kayak and an abroad product were carried out in the Ocean engineering Basin. Resistance test was carried out by using downscale model in the circulating water channel. Through method of following performance evaluation, advantage and disadvantage of the developed inflatable kayak were compared with those of the abroad product.

• Journal of the Society of Naval Architects of Korea
• /
• v.48 no.5
• /
• pp.421-425
• /
• 2011

To know the speed performance of "ARAON" in Arctic ice field, the measurement of ice properties which is ice thickness & strength, snow depth and free board were performed on July 2010. The measuring method of nautical signals such as heading angle, power of engine, wind & current information etc. was described in this paper. The speed sea trials in ice were performed on the four different positions with different ice properties and engine powers because the uniform level ice is not detected in the Chukchi Sea. The test field was partially constrained ice floe with hummocks and it was superposed with small broken ice pieces each other. All of the measured ice properties were compared and evaluated according to the results of sea trial. The relations between speed, ice thickness, strength and power were summarized. Consequently according to the sea trial results, the speed of ARAON is 2.78knots at the 2.49m ice thickness with 6.55MW engine power.

• Journal of the Society of Naval Architects of Korea
• /
• v.49 no.6
• /
• pp.478-483
• /
• 2012

The speed performances of ice sea trial on the Arctic(2010 & 2011) area were shown different results depend on the ice floe size. Penetration phenomena of level ice was not happened on medium ice floe and tore up by the impact force because the mass of medium ice floe is similar to the mass of Araon which is Korean ice breaking research vessel and did not shut up by the ice ridge or iceberg. The sea trial on the Amundsen sea was performed at the big floe which is classified by WMO(World Meteorological Organization). Three measurements of ice properties and five results of speed trial were obtained with different ice thicknesses and engine powers. To evaluate speed of level ice trial and model test results at the same ice thickness and engine power, the correction method of HSVA(Hamburg Ship Model Basin) was used. The thickness, snow effect, flexural strength and friction coefficient were corrected to compare the speed of sea trial. The analyzed speed at 1.03m thickness of big floe was 5.85 knots at 10MW power and it's 6.10 knots at 1.0m ice thickness and the same power. It's bigger than the results of level ice because big floe was also slightly tore up by the impact force of vessel based on the observation of recorded video.

• Journal of the Society of Naval Architects of Korea
• /
• v.38 no.3
• /
• pp.54-61
• /
• 2001

It is expected that ISO issue a standard method for sea trial and the correction of data taken during speed trial. One of the major reason for this effort(or trend) is to get reliable and accurate sea trial measurement. With the same philosophy, SHI(Samsung Heavy Industries) developed a nautical signal integrated unit in 1996. Two years after this, SHI developed a software that enable the user to analyze the sea trial measurement on-board. After a series of stationary and performance tests, KR has issued a certificate for international application of the software. We have been utilizing this program for the measurement and analysis of sea trial of more than 70 ships built in SHI shipyard. However, one critical defect of the software has been that it can be applied only for single shaft vessels. In this short paper, we would like to introduce a new version of the software which can be used for both single and multi thruster vessels. This paper deals with the introduction, test method and some of the test result.

• The Korea Journal of Herbology
• /
• v.34 no.1
• /
• pp.13-21
• /
• 2019

Objectives : This clinical trial is performed to investigate the effect of improving the hypersensitivity reaction and the safety of powdered ethanol extract Codonopsis lanceolata (S. et Z.) Trautv. for allergic patients. Methods : This study was randomized, double blinded, placebo-controlled clinical trial. 60 allergic rhinitis subjects were randomly assigned to Treatment group(n=30) and Control group(n=30). They were received the test substance or placebo in their $1^{st}$ and $2^{nd}$ visit, and took it once a day, 1 powder bag per 1 time, for 8 weeks. The freeze dried powder of Codonopsis lanceolata (S. et Z.) Trautv. was mixed with 30% ethanol and the filtrate was collected thrice with constant stirring of the mixture. The placebo was prepared in the same form as the test substance by replacing with corn starch. Total Nasal Symptom Score(TNSS) questionnaires and laboratory tests were performed at the screening and last visit to evaluate the efficacy. And to assess safety, vital signs and adverse events were confirmed at every visit. Statistical analysis about the result was performed using SAS 9.4. Results : In treatment group, there was a significant decrease in B cell after taking the test substance(p<0.005). And there was a statistically significant difference between groups(p<0.005). Changes in nasal symptoms were not statistically significant between groups, and both groups showed statistically significant differences before and after the test(p<0.0001). Also there were no adverse events associated with the clinical trial product. Conclusions : This clinical trial showed that Codonopsis lanceolata (S. et Z.) Trautv. extract was helpful in improving the hypersensitivity reaction in allergic patients without significant side effects.