• Journal of the Optical Society of Korea
• /
• v.15 no.2
• /
• pp.132-139
• /
• 2011

We investigate theoretically the combined effect of fiber chromatic dispersion and self-phase modulation (SPM) on multi-channel subcarrier multiplexed (SCM) optical transmission systems in terms of the detected RF carrier power and SPM-induced power gain after transmission over single-mode fiber (SMF) links. According to the calculated power gain due to the SPM effect at the transmission distance of P3dB using the detected radio-frequency (RF) carrier power after photo-detection, the power gain is significantly degraded with large optical modulation index (OMI), small SCM channel spacing, and large fiber launching power because of the increased interaction between subcarrier channels. The nonlinear phase shift due to linear and nonlinear fiber characteristics is investigated to explain these results in detail. The numerical simulation results show that the OMI per SCM channel has to be smaller than 10 % for the fiber launching power of 10 dBm to guarantee prevention of SPM-induced power gain degradation below 0.5 dB for the SCM system with the channel spacing of 100 MHz. This result is expected to be utilized for the optical transmission systems using the SCM technology in future radio-over-fiber (RoF) networks.

• Journal of Fashion Business
• /
• v.7 no.3
• /
• pp.45-53
• /
• 2003

In the face of trade opportunity of Chinese reformation and opening and the future largest single market, global or multinational companies and Korean, Japanese, Chinese, Hong Kong's and Taiwan's companies will go all out to catch hold of one quotient. One trading war is about to start for funds, elitists, technique, and management in China now. It might be difficult to get profits in Chinese markets. However, risks can bring challenges, and competition can make progress. It's time to prepare for the challenges in the golden opportunity laid in front of us all.

• The International Journal of Costume Culture
• /
• v.13 no.2
• /
• pp.104-117
• /
• 2010

The purpose of this study is to find out the effect of on-the-job experiencing program on the formation of dynamics such as creativity, organizing, and clarity necessary for launching into the society through a cause-and-effect analysis to determine the priority of resources investments and improvements of educational courses. As a result, the selling experience and planned workshop were found to have effect on the creative dynamic that preparatory business starters must secure without fail. This means that e-Fashionn Lab(http://www.bc2d.com) which is an experiencing program, is fully accomplishing its initial objective set up at the time of the system design. In addition, the selling experience and the mini-home page experience were found to have effect on the formation of organizing dynamic of preparatory business starters. This shows that the system design to realize the database of personal friendships and personal information is being used fully as an educational practice instruments. Lastly, the selling experience and planned workshops were found to have effect on the formation of clarity dynamic of preparatory business starters as experiencing characteristic has effect on creativity. However, the community (work room) experience was found to have no effect on the formation of dynamics necessary for preparatory business starters to advance into the society at this study. This signifies that the system input resources should be pushed back in priority and that curriculums and system design should be concentrated on strengthening the selling experience and planned workshop in general.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.5
• /
• pp.1753-1755
• /
• 2012

This was a survey research conducted in Northestern Thailand during 2009-2010 and designed to evaluate the success of a health education program by comparing levels of health knowledge in the community before and after the launching of a Multi-professional Intervention and Training for Ongoing Volunteer-based Community Health Programme. The survey questionnaire included items about demographic characteristics and health knowledge. The participants were 1,015 members of various communities, who were randomly selected to be included in the survey before launching the intervention, and 1,030 members of the same communities randomly selected to be included in the survey after the intervention was completed. The demographic characteristics of both groups were similar. Overall knowledge and knowledge of all the diseases, except lung and cervical cancer, were significantly higher after the intervention. In conclusion, a Volunteer-based Community Health Programme has advantages for areas where the numbers of health personnel are limited. The use of trained community health volunteers may be one of the best sustainable alternative means for the transfer of health knowledge.

• Atmosphere
• /
• v.21 no.2
• /
• pp.185-196
• /
• 2011

The performance assessment in radiosonde observation on the special observation program (ProbeX-2009) is performed and the characteristics of precipitation using Auto Weather System (AWS) and radiosonde data in 2009 at the Ulleungdo are investigated. The launching time, observation time, and maximum altitude of radiosonde are satisfied with the regulation from Korea Meteorological Administration (KMA) and World Meteorological Organization (WMO) but the duration of observational time of radiosonde is much shorter than that of the ProbeX-2007 because the altitude of launching site is higher than others in 2007. From the analysis of trajectories of radiosonde, most radiosondes at the Ulleungdo tend to move into the east because the westerly prevail at the middle latitude. However, when the Okhotsk high is expanded to the Korean peninsula and the north-westerly winds strengthen over the East Sea as the subtropical high is retreated, radiosonde tends to move into the south-west and south-east, respectively. Maximum distance appears at the end of observation level before May but the level of maximum distance is changed into 100 hPa after June because the prevailing wind direction is reversed from westerly to easterly at the stratosphere during summer time. The condition of precipitation was more correlated with the dynamic instability except Changma season. Precipitation in 2009 at the Ulleungdo occurred under the marine climate so that total precipitation amounts and precipitation intensity were increased and intensified during nighttime. The local environment favorable for the precipitation during nighttime was while the wind speed at the surface and the inflow from the shoreline were strengthened. Precipitation events also affected by synoptic condition but the localized effect induced by topography was more strengthened at the northern part of Ulleungdo.

• Composites Research
• /
• v.28 no.4
• /
• pp.162-167
• /
• 2015

Composite sandwich structures are widely employed in various applications, due to their high specific stiffness and specific bending strength compared to solid panels. Lately, for that reason, the advanced composite sandwich structures are employed in satellite structures: materials should be as light as possible with the highest attainable performance. This study is majorly focused on inserts employed to the composite sandwich satellite structures. A new hybrid insert design was developed in precedent study to reduce the mass of the sandwich structure since the mass of the satellite structure is related to high launching cost [1]. In this study, the thermal characteristics and behavior of the precedently developed hybrid insert with carbon composite reinforcing web and the conventional partial insert were numerically investigated.

• Journal of Applied Reliability
• /
• v.17 no.3
• /
• pp.207-212
• /
• 2017

Purpose: This article provides an efficient cushion molding method for improving reliability of the rotation driving system. Method: Allowable stress level for cushion is calculated by using physical characteristics of the rotation driving system. In addition, various test units are manufactured and used to conduct the rebound resilience, the burst pressure and the alternating load test. Results: Actual allowable stress level and test results of the rebound resilience, the burst pressure and the alternating load test are provided. Conclusion: The cushion manufactured by the compression molding method gives more preferable characteristics for improving the reliability of the rotation driving system.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.31 no.8
• /
• pp.1180-1189
• /
• 2007

The purpose of this study is to search the level of localization strategy of imported brands in Korean Market, to investigate relationship between the brand characteristics and localization strategy, and to study the case about localization strategy of the brand selected according to the type of brand. The survey research was employed and for the data analysis, descriptive statistics, one-way ANOVA, and multiple-regression were used. For the case study, interview with the person who works in the each kind of company was used. The results of this study were as follows: Firstly, the level of localization strategy is found in order price, place, promotion and product. Secondly among the brand characteristics, type of brand, proportion of garments, price zone, launching time, number of shop are related with localization strategy, but turnover and number of the staff are not. Thirdly, license brand has the characteristics like as national brands and the differences between the branch and the agent is confidence and communication that are the basic elements of localization. This study can help national brands to refer the localization strategy and provide the understanding of localization strategy of imported brands in Korean fashion market.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.16 no.5 s.96
• /
• pp.541-548
• /
• 2005

The research deals with the prediction and the measurement of electromagnetic wave propagation in rectangular shaped tunnels at f=2.65 GHz. The received power level was measured in the straight and the curved tunnel by using a spectrum analyzer and Satellite DMB mobile phone. Thus we have gotten the data for two cases, the straight and the curved tunnel whose radius is 300m. In addition, the prediction of wave propagation was conducted based on the ray-launching method, in same tunnel where measurement was performed. A good agreement of the measured and the predicted path loss could be confirmed. The measured path loss shows a marked difference in propagation loss: the path-loss exponent, 3.21, and 3.98, for a straight and a curved tunnel, respectively. The reason that path-loss exponent is high in a curved tunnel is that there is no direct wave but only the reflected waves, which attenuates rapidly with distance due to multiple reflections. Also the predicted path loss shows path loss exeponent, 3.2 and 3.95, for a straight and a curved tunnel which are similar to the simulation results.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.14 no.4
• /
• pp.325-331
• /
• 2008

Recently, new shipbuilding yards with medium capacity are established due to influence of prosperous condition no shipbuilding industry in Korea. These shipbuilding yards have characteristics such as high capacity facilities and followed system of dock launching just like major shipbuilding yards. The present paper explains the dry dock design and structural strength analysis by using FEM. The design stage used TRIBON M3 system while the estimation of structural strength used ANSYS Multiphysics module. The dry dock gate did not frequently open and close, it had to sustain against external wave load during building a ship. Moreover, documents related to design of dry dock gate have no guidelines about design criterion and process of structural strength calculation. It is necessary to make the guidelines about design of dry dock gate. It is expected that this paper will be a good reference to the design of dry dock gate.