• Journal of Advanced Navigation Technology
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• v.26 no.6
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• pp.393-403
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• 2022

Various studies suggest that the initial operating form of UAM, which is being presented as a solution to the urban traffic problem, will be similar to VTOL aircraft among current aircraft. In a form similar to determining the direction of the runway where fixed-wing aircraft take off and land, the vertiport where take-off and landing of VTOL aircraft takes place determines the flight direction of departure and arrival in consideration of the direction of the wind. Unlike areas where airports are generally built, in the case of downtown areas, it is expected that the characteristics of wind may continuously change depending on the environment of changing terrain or obstacles such as the construction of new buildings. In this study, long-term actual observation data for reviewing the take-off and landing directions at the city center where the location of the vertiport is expected are compared using a wind speed map, and the characteristics of the ground wind and the possibility of change in the direction of the predominant wind depending on the observation period and observation location confirmed.

• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.941-946
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• 2023

To improve the lift, cruise speed, and range of eVTOL aircraft, which are being considered as future transportation vehicles, this paper introduces the concepts of Tilt Rotor and Tandem Wing to the aircraft. We developed an aircraft and conducted flight experiments to obtain flight videos and flight logs. The results of the analysis of the flight videos and flight logs showed that the aircraft's moment was excessively forward and the attitude was not recovered. To address this problem, we modified the wing incidence angles and surface areas in XFLR5 to obtain the optimal pitching moment coefficients to ensure vertical stability. We then analyzed the redesigned aircraft, developed using CATIA, through XFLR5. The results of this study provide valuable insights, suggesting that the incorporation of Tilt Rotor and Tandem Wing designs can contribute to achieving stable pitching moment coefficients. This innovative approach offers a promising avenue to significantly enhance vertical stability in UAM vehicles, paving the way for future advancements in the field.

• Wind and Structures
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• v.38 no.2
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• pp.129-146
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• 2024

Aiming at the problem of non-stationary wind field simulation of downbursts, a non-stationary down-burst generation system was designed by adding a nozzle and program control valve to the inlet of the original wall jet model. The computational fluid dynamics (CFD) method was used to simulate the downburst. Firstly, the two-dimensional (2D) model was used to study the outflow situation, and the database of working conditions was formed. Then the combined superposition of working conditions was carried out to simulate the full-scale measured downburst. The three-dimensional (3D) large eddy simulation (LES) was used for further verification based on this superposition condition. Finally, the wind tunnel test is used to further verify. The results show that after the valve is opened, the wind ve-locity at low altitude increases rapidly, then stays stable, and the wind velocity at each point fluctuates. The velocity of the 2D model matches the wind velocity trend of the measured downburst well. The 3D model matches the measured downburst flow in terms of wind velocity and pulsation characteris-tics. The time-varying mean wind velocity of the wind tunnel test is in better agreement with the meas-ured time-varying mean wind velocity of the downburst. The power spectrum of fluctuating wind ve-locity at different vertical heights for the test condition also agrees well with the von Karman spectrum, and conforms to the "-5/3" law. The vertical profile of the maximum time-varying average wind veloci-ty obtained from the test shows the basic characteristics of the typical wind profile of the downburst. The effectiveness of the downburst generation system is verified.

• Journal of Korean Society of Steel Construction
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• v.10 no.3 s.36
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• pp.553-564
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• 1998

Recently, more and more steel-deck structural system for two story roads has been adopted as a solution against traffic congestion in urban area, mainly because of fast construction, reduced self-weight, higher stiffness and efficient erection compared to that of concrete decks. The main objective is to study on the unit-elective optimal type and proportioning of a rational steel-deck system for two story roads using an optimum design program specifically developed for steel-deck systems. The objective function for the optimization is formulated as a minimum cost design problem. The behavior and design constraints are formulated based on the ASD(Allowable Stress Design) criteria of the Korean Bridge Design Code. The optimum design program developed in this study consists of two steps - the first step for the optimization of the steel box or plate girder viaducts, and the second step for the optimum design of the steel-decks with closed or open ribs. A grid model is used as a structural analysis model for the optimization of the main girder system, while the analysis of the deck system is based on the Pelican-Esslinger method. The SQP(Sequential Quadratic Programming) is used as the optimization technique for the constrained optimization problem. By using a set of application examples, the rational type related to the optimized steel-deck system designs is investigated by comparing the cost effectiveness of each type. Based on the results of the investigation it may be concluded that the optimal linear box girder and deck system with closed ribs may be utilized as one of the most rational and economical viaducts in the construction of two-story roads.

• Journal of Digital Convergence
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• v.11 no.5
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• pp.355-370
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• 2013

This study was aimed at the married immigrant women and was attempted to provide the basic data of the nursing practice useful in identifying the relationship aspects and the influence of resilience factor and promoting the family adaptation. This study was conducted for the married immigrant women who were located in urban-rural complex area around Daejeon city and in Chungnam region, and the multi-cultural families supporting program of community welfare halls among those who had resided over 1 year in Korea. The data was collected from Feb, 2012 to July, 2012 and in the end, 216 questionnaires were made the subjects of data analysis. For the collected data, frequency analysis, percentage, ANOVA, t-test and correlation analysis were conducted using SPSS, LISREL. The overall index of hypothesis model showed a good congruence like ${\chi}^2$ = .06 (p= .812), df=1, ${\chi}^2$(df)=.06, GFI=1.0, AGFI= 1.0, SRMR=.002, NFI= 1.0, NNFI=1.0, RMSEA=0.000, CN=266. Looking at the results of hypothesis testing suggested by the model, the variables which affected the family adaptation were family stress and parenting stress, while social support, family hardness, problem solving communication, and problem solving coping didn't affect the family adaptation. It is considered that based on the results of this study, nursing intervention which helps the family adaptation of the married immigrant women who are in a crisis situation must be done with a program which can help them have a positive view on the stress situation and reduce the stress happening in the family relationship and parenting.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7295-7302
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• 2015

Background: Lung cancer has been a major health problem in developed countries for several decades, and has emerged recently as the leading cause of cancer death in many developing countries. The incidence of lung cancer appears to be increasing more rapidly in rural than in urban areas of China. This paper presents the trends of lung cancer incidence and survival derived from a 40-year population-based cancer monitoring program in a rural area, Qidong, China. Materials and Methods: The Qidong cancer registration data of 1972-2011 were used to calculate the crude rate, age-standardized rate by Chinese population (CASR) and by world population (WASR), birth cohort rates, and other descriptive features. Active and passive methods were used to construct the data set, with a deadline of the latest follow-up of April 30, 2012. Results: The total number of lung cancer cases was 15,340, accounting for 16.5% of all sites combined. The crude incidence rate, CASR and WASR of this cancer were 34.1, 15.7 and 25.4 per 100,000, respectively. Males had higher crude rates than females (49.7 vs 19.0). Rapidly increasing trends were found in annual percent change resulting in lung cancer being a number one cancer site after year 2010 in Qidong. Birth cohort analysis showed incidence rates have increased for all age groups over 24 years old. The 5 year observed survival rates were 3.55% in 1973-1977, 3.92 in 1983-1987, 3.69% in 1993-1997, and 6.32% in 2003-2007. Males experienced poorer survival than did females. Conclusions: Lung cancer has become a major cancer-related health problem in this rural area. The rapid increases in incidence likely result from an increased cigarette smoking rate and evolving environmental risk factors. Lung cancer survival, while showing some improvement in prognosis, still remains well below that observed in the developed areas of the world.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.4
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• pp.63-68
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• 2010

Utility-Pipe Conduit is, Housing and city effectively accommodate what they absolutely need power, communications, gas, pipeline, water supply, drainage, energy facilities etc, according to expansion of urban infrastructure are derived, several ways to solve problems in, collection facilities in place are maintained and managed facility. If Utility-Pipe Conduit is damaged, as well as national security, because their impact on society as a whole, by introducing large vulnerability in the fire prevention activities and suppression measures and disaster for our situation by introducing measures, comprehensive analysis of the fire risk, it shall establish fire prevention activities and suppression through analysis of Utility-Pipe Conduit design, institutional issues, the problem of fire protection facilities, fire spread phenomenon etc. Because of Utility-Pipe Conduit is an enclosed place, so incomplete combustion due to lack of oxygen supply that there are problem such dark smoke, carbon monoxide etc, toxic combustion products and heat generation and visual impairment is an issue difficult to enter. As well as fire prevention activities, the fire In light of the particularity of the under ground than above ground fire, so this phenomenon is weak fire fighting that fire to become effective fire fighting tactics, basically it is necessary difficulty softening, non-burn softening and prevent combustion expansion of the cable is installed on the Utility-Pipe Conduit, having to considering the specificity of the response command system and relevant organizations to establish an on-site, Structural identification and other information gathering required to record of Response agencies, keep air conditioning system 24 hours and strengthening Virtual Total Training of Response agen

• Journal of Korean Society of Transportation
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• v.33 no.1
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• pp.70-80
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• 2015

In recent years, tram has been the focus of a new mode of public transportation that can solve traffic jams and decrease public transit usage and environmental problem. This research is in the works to develop a tram signal controller and signal control strategies, and aim to resolve the problem of what could happen if a tram system was installed in general road. We developed the hierarchical signal control strategies to obtain a minimum tram bandwidth and to minimize vehicle delay, in order to perform a priority control to include passive and active signal priority control strategies. The strategies was produced for S/W and H/W, it is based in standard traffic signal controller. We conducted a micro simulation test to evaluate the hierarchical signal control strategies, which showed that the developed optimization model is effective to prevent a tram's stop in intersection, to reduce a tram's travel time and vehicle's delay.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.1895-1899
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• 2012

Background and Aims: Liver cancer is a major health problem in low-resource countries. Approximately 55% of all liver cancer occurs in China. Hebei Province is one of the important covering nearly 6% of the population of China. The aim of this paper was to explore liver cancer mortality trends during past 30 years, and provide basic information on prevention strategies. Methods: Hebei was covered covered all the three national surveys during 1973-1975, 1990-1992, and 2004-2005 and one provincial survey during 1984-1986. Subjects included all cases dying from liver cancer in Hebei Province. Liver cancer mortality trend and geographic differences across cities and counties were analyzed. Results: There were 82,878 deaths in Hebei Province during 2004-2005 with an average mortality rate was 600.9/10,000, and an age-adjusted rate of 552.3/10,000. Those dying of cancer were 18,424 cases, accounting for 22.2% of all deaths, second only to cerebrovascular disease as a cause of death. Cancer mortality was 133.6/100,000 (age-adjusted rate was 119.2/100,000). Liver cancer ranked fourth in this survey with a mortality rate of 21.0/100,000, 28.4/100,000 in males and 13.35/10,000 in females, accounting for 15.7%, 17.1% and 13.4% of the total number of cancer deaths and in males and females, respectively. The sex ratio was 2.13. Since the 1970s, liver cancer deaths of Hebei province have been increasing slightly. The crude mortality rates in the four surveys were 11.3, 16.0, 17.4, 21.0 per 100,000, respectively, with age-adjusted rates fluctuating during the past 30 years, but the trend also being upwards. There is a tendency for the mortality rates to be higher in coastal than mountain areas, and is relative lower in the plain area, with crude mortality rates of 25.3, 22.1, and 19.1 per 100,000, respectively. There were no notable differences in cride data between urban and rural, but the age-adjusted mortality rate in rural was much higher. Conclusion: Our study indicated that the mortality of liver cancer in Hebei Province is lower than the national average level. There is a slightly increase trend, especially in some counties. Liver cancer is a major health problem and it is necessary to further promote prevention strategies in Hebei province.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.323-335
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• 2017

Recently, Korea is facing a trend of a fast-paced change towards a multi-cultural society, accompanied by the consequential increase in population and many changes in the peripheral environment. Particularly, the influx of multi-cultural families in Ansan City is increasing every year, but their housing environment remains in poor conditions. Actually, the research on housing policy for multi-cultural families and their housing satisfaction is restrictive. It is therefore necessary to research on how to overcome this problem, and what realistic policy alternatives are required. The purpose of this study is to present some policy alternatives to improve the housing satisfaction of the Korean-Chinese residing in Ansan City. To this end, this study conducted empirical analysis with a focus on Korea-Chinese multi-cultural families living in Ansan City through a questionnaire. As the analysis method, this study conducted frequency analysis, descriptive statistical analysis, cross analysis, and regression analysis, and used the statistical package-SPSS 20.0 as an analysis tool. As a result of the research, first, it was found that their awareness of the government housing policy is insufficient; second, they had a lot more hardships in housing due to the problem of the rising house prices caused by urban development & regeneration; third, in terms of housing tenure type, there was a higher proportion of a lease on a deposit basis and monthly rent than owner-occupied housing. Hence, this study drew the conclusion that the Korean-Chinese multi-cultural family's housing environment needs to be improved and policy support is required for Korean-Chinese. In addition, this study gives great significance in providing these research results as basic materials which make it possible to inquire into mutually reciprocal practice plan and strategic alternatives for a multi-cultural families from now on.