• Journal of Korean Tunnelling and Underground Space Association
• /
• v.20 no.6
• /
• pp.1073-1090
• /
• 2018

Since the domestic utility tunnels were built mainly in the development project of the new city, they are all in the form of cut-and-cover box tunnel. But, in the case of overseas construction of utility tunnels for existing urban areas, the bored tunnel types are mainly adopted. It is reasonable to install bored tunnels in a downtown area because it is difficult to block the roads or install bypass roads due to heavy traffic and civil complaints. In order to activate the utility tunnels in bored type, it is necessary to secure optimized cross-sectional design technology considering the optimal supplying capacity and mutual influencing factors (Thermal Interference, electrolytic corrosion, efficiency of the maintenance, etc.) of utilities (power cables, telecommunication cables, water pipes, etc.). The optimal cross-section design method for bored utility tunnels is ultimately to derive the optimal arrangement technique for the utilities. In order to develop the design methods, firstly, the cases of tunnel cross-section (Shield TBM, Conventional Tunneling) in overseas shall be investigated to analyze the characteristics of the installation of utilities in the section and installation of auxiliary facilities, It is necessary to sort out and analyze the criteria related to the inner cross-section design (arrangement) presented in the standards and guidelines.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.49 no.2
• /
• pp.107-120
• /
• 2021

Electric-powered distributed propulsion aircraft possess a complex wake flow and mutual interference with the airframe, due to the use of many propellers. Accordingly, in the early design stage, rapid aerodynamic and load analysis considering the effect of propellers for various configurations and flight conditions are required. In this study, an efficient panel-based aerodynamic analysis method that can take into account the propeller effects is developed and validated. The induced velocity field in the region of propeller wake is calculated based on Actuator Disk Theory (ADT) and is considered as the boundary condition at the vehicle's surface in the three-dimensional steady source-doublet panel method. Analyses are carried out by selecting an isolated propeller of the Korea Aerospace Research Institute (KARI)'s Quad Tilt Propeller (QTP) aircraft and the propeller-wing configuration of the former experimental study as benchmark problems. Through comparisons with the results of computational fluid dynamics (CFD) based on actuator methods, the wake velocity of propeller and the changes in the aerodynamic load distribution of the wing due to the propeller operation are validated. The method is applied to the analysis of the Optional Piloted Personal Aerial Vehicle (OPPAV) and QTP, and the practicality and validity of the method are confirmed through comparison and analysis of the computational time and results with CFD.

• Korean Journal of Culture and Social Issue
• /
• v.29 no.4
• /
• pp.497-536
• /
• 2023

This study was conducted with the purpose of exploring the relationship dynamics of couples who experienced dating violence. For this purpose, interviews were conducted with 15 couples who experienced dating violence. The collected data was analyzed using the consensual qualitative research(CQR) method. As a result, 3 domains, 13 categories, and 30 subcategories were derived. Domain 1 was about "the direction of the dynamics of perpetration and victimization, types of violence, and experience level," and found that the dynamics of perpetration and victimization are bidirectional, and that there are situational and controlling types of violence. For domain 2, we explored "major conflict themes, unique perceptions, and psychological dynamics of violence" and identified "other and communication issues" and "interference and personality issues" as major conflict themes, "gender stereotypes" and "violence permissive beliefs" as unique perceptions, and "attribution styles," "major emotions," and "coping styles" as psychological dynamics of violence. For domain 3, we looked into the 'changes in commitment and satisfaction as well as relationship maintenance factors' and presented changes in commitment and satisfaction, and found that the relationship maintenance factors were divided into positive and negative factors. These results are significant in that dating violence consists of mutual abuse and that it empirically revealed the detailed elements of the psychological dynamics of male and female. This was compared and analyzed with previous studies, and limitations and future research were also presented.