• Korean Journal of Social Welfare
• /
• v.67 no.2
• /
• pp.33-60
• /
• 2015

The purpose of this study was to analyze the life experiences of fifteen marriage immigrant Asian women who went through running away from their home countries, marrying with Korean men, divorcing from their husbands, and coping with many difficulties after their divorce in Korean society. In order to conduct this study grounded theory methods have been employed. The central phenomenon digged out from this study was 'resistance to baffled reality' (i. e. dislocation). The causal conditions which brought about the central phenomenon were 'escaping for survival' and 'experiencing the gap between reality and expectation. 'The intervening conditions included 'getting to know the reality of their husbands,' 'losing hope,' and 'not being able to pull themselves together.' The contextual conditions consisted of 'being treated as maids,' 'becoming victims of family violence,' 'making up their minds to survive,' 'securing future life,' 'being marginalized,' and 'being aware of themselves as strangers.' The action/interaction strategies on the central phenomenon were 'building support systems,' 'building up will for new life,' and 'reconstructing social identity.'The final outcome was 'arranging places of new settlement.' The divorce was classified as four types: 'coping and growth,' 'emancipation and settling down,' 'being overwhelmed by livelihood,' and 'continuous wandering.' Based on these results, this study provided a few political and practice suggestions to prevent family violence and divorces among multi-cultural families, and also to bumper the impacts of divorce.

• Structural Engineering and Mechanics
• /
• v.74 no.6
• /
• pp.821-832
• /
• 2020

The fundamental period is an important parameter for seismic design and seismic risk assessment of building structures. In this paper, a simplified theoretical method to predict the fundamental period of masonry infilled reinforced concrete (RC) frame is developed based on the basic theory of engineering mechanics. The different configurations of the RC frame as well as masonry walls were taken into account in the developed method. The fundamental period of the infilled structure is calculated according to the integration of the lateral stiffness of the RC frame and masonry walls along the height. A correction coefficient is considered to control the error for the period estimation, and it is determined according to the multiple linear regression analysis. The corrected formula is verified by shaking table tests on two masonry infilled RC frame models, and the errors between the estimated and test period are 2.3% and 23.2%. Finally, a probability-based method is proposed for the corrected formula, and it allows the structural engineers to select an appropriate fundamental period with a certain safety redundancy. The proposed method can be quickly and flexibly used for prediction, and it can be hand-calculated and easily understood. Thus it would be a good choice in determining the fundamental period of RC frames infilled with masonry wall structures in engineering practice instead of the existing methods.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.26 no.6
• /
• pp.415-421
• /
• 2013

In order to extend the service life of a nuclear power plant(NPP) ensuring the structural safety, effective and efficient management of NPP considering structural deteriorations and various natural hazard risks has been treated as a significant tool(IAEA 1998). The systemic efforts is required to prevent the potential loss of NPPs resulting from the natural hazard including earthquakes, hurricane and flooding since the Fukushima accident. Earthquake risk of building structures can be mitigated through appropriate seismic isolation system installation. It has been known that a seismic isolation system can lead to reduction of the deleterious effect on ground motion induced by earthquakes, and structural safety can be improved. In this paper, the NPP life-cycle management is reviewed. Furthermore, effect of seismic isolation on the NPP life-cycle cost analysis with earthquake, and cost-benefit analysis in terms of life-cycle cost when applying the seismic isolation systems to NPP are introduced.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.6 no.5
• /
• pp.1303-1315
• /
• 2012

In the draft of the IEEE 802.11s standard, a tree topology is established by the proactive tree-building mode of the Hybrid Wireless Mesh Protocol (HWMP). It is used for cases in which the root station (e.g., gateway) is an end point of the majority of the data connections. In the tree topology, the root or central stations (e.g., parent stations) are connected to the other stations (e.g., leaves) that are one level lower than the central station. Such mesh stations are likely to suffer heavily from contention in bottleneck links when the network has a high traffic load. Moreover, the dependence of the network on such stations is a point of vulnerability. A failure of the central station (e.g., a crash or simply going into sleep mode to save energy) can cripple the whole network in the tree topology. This causes performance degradation for end-to-end transmissions. In a connected mesh topology where the stations having two or more radio links between them are connected in such a way that if a failure subsists in any of the links, the other link could provide the redundancy to the network. We propose a scheme to utilize this characteristic by organizing the network into concentric tiers around the root mesh station. The tier structure facilitates path recovery and congestion control. The resulting mode is referred to as Tier-based Proactive Path Selection Mode (TPPSM). The performance of TPPSM is compared with the proactive tree mode of HWMP. Simulation results show that TPPSM has better performance.

• Journal of the Korean Solar Energy Society
• /
• v.30 no.6
• /
• pp.81-88
• /
• 2010

This study compared the feasibility of utilizing a wood bioenergy system over a conventional central heating and cooling system and a cogeneration system in an apartment complex. The performance of the three systems were compared in the following areas: energy consumption, environmental impact(output of CO2, CH4, and N2O), and life cycle cost. The results showed that energy performance of the wood bioenergy system was similar to the conventional central system (just a 1% improvement) but the cogeneration system showed a 12% reduction in energy consumption compared to the conventional system. In terms of environmental impact, the bioenergy system reduced pollutants by 50% while the cogeneration system reduced pollutants by 30% compared to the conventional system. Life cycle cost analysis indicated bioenergy and cogeneration to have an 8% and 19% improvement over the conventional system. The findings of the study suggest that it is both economically and environmentally beneficial to use a wood bioenergy system in place of a conventional central heating and cooling system in apartment complexes.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.10 no.1
• /
• pp.95-102
• /
• 2018

This paper proposes a dual lifting and its cooperative control system with two different kinds of floating cranes. The Mega-erection and Giga-erection in the ship building are used to handle heavier and wider blocks and modules as ships and off-shore platforms are enlarged. However, there is no equipment to handle such Tera-blocks. In order to overcome the limit on performance of existing floating cranes, the dual lifting is proposed in this research. In the dual lifting, two floating cranes are well-coordinated to add up the lift capabilities of both cranes without any loss such that virtually a single crane is lifting, maneuvering and unloading. Two main constraints for the dual lifting are as follows: First, two barges of floating cranes should be constrained as a rigid body not to cause a relative motion between two barges and main hooks of the two cranes should be controlled as main hooks of a single crane. In order words, it is necessary to develop the cooperative control of two floating cranes in order to sustain a center of gravity of the module and minimize the tilting angle during the lifting and unloading by the two floating cranes. Two floating cranes are handled as a master-slave system. The master crane is able to gather information about all working conditions and make a decision to control the individual hook speed, which communicates the slave crane by TCP/IP. The developed control system has been embedded in the real floating crane systems and the dual lifting has been demonstrated five times at SHI shipyard in 2015. The moving angles of the lifting module are analyzed and verified to be suitable for hoisting control. It is verified that the dual lifting can be applied for many heavier and wider blocks and modules to shorten the construction time of ships and off-shore platforms.

• Korean Journal of Family Social Work
• /
• no.23
• /
• pp.225-262
• /
• 2008

The purpose of this study was to improve the understanding of essential experiences of children of Alcoholism and explore their adjustment process from the children's perspectives. The specific research questions explored in this study were: 1. What was the central phenomenon that children of Alcoholism have experienced? 2. What was the adjustment process of the children of Alcoholism. The grounded theory was adopted in this study to address the research questions. Data was collected through in-depth interviews with eight young adult aged from 18-30 years olds who experienced their parent's Alcoholism. Grounded theory based data analyses resulted in 85 concepts, 30 sub-categories, and 16 categories. The 'causal conditions' influencing the central phenomenon was 'self denial' and 'being suppressed' is the central phenomenon for the children of Alcoholism. The core issue in the process of an adjustment of children from a Alcoholism family was 'accepting the parental Alcoholic problem and re-defining the self', The results of this study suggest that counseling interventions are suggested to improve children's well-being and facilitate their adjustment. Therefore this study has implication on building theory of intervention on the offsprings who have parents of Alcoholism.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.17 no.4
• /
• pp.1147-1161
• /
• 2023

The Internet of Things (IoT) requires a new processing model that will allow scalability in cloud computing while reducing time delay caused by data transmission within a network. Such a model can be achieved by using resources that are closer to the user, i.e., by relying on edge computing (EC). The amount of IoT data also grows with an increase in the number of IoT devices. However, building such a flexible model within a heterogeneous environment is difficult in terms of resources. Moreover, the increasing demand for IoT services necessitates shortening time delay and response time by achieving effective load balancing. IoT devices are expected to generate huge amounts of data within a short amount of time. They will be dynamically deployed, and IoT services will be provided to EC devices or cloud servers to minimize resource costs while meeting the latency and quality of service (QoS) constraints of IoT applications when IoT devices are at the endpoint. EC is an emerging solution to the data processing problem in IoT. In this study, we improve the load balancing process and distribute resources fairly to tasks, which, in turn, will improve QoS in cloud and reduce processing time, and consequently, response time.

• Journal of Korean Society for Geospatial Information Science
• /
• v.25 no.1
• /
• pp.55-61
• /
• 2017

The V-world, korean type spatial information open platform, provides various services to easily utilize 2D, 3D map and administrative information of the country. Among them, V-world 3D map service, modeled in individual building unit, require requests for each building model file and the draw calls for drawing models on the screen by the request. This causes a large number of model requests and draw calls to occur that increase the latency occurring during the transmission and conversion process between the central processing unit(CPU) and the graphic processing unit(GPU), which lead to the performance degradation of the 3D map service. In this paper, we propose a performance improvement plan to reduce the performance degradation of 3D map service caused by multiple model requests and draw calls. Therefore, we tried to reduce the number of requests and draw calls for the model file by applying a 3D tile model that combined multiple building models to single tile. In addition, we applied the quadtree algorithm to reduce the time required to load the model file by shortening the retrieval time of the model. This is expected to contribute to improving the performance of 3D map service of V-world.

• Korean Journal of Construction Engineering and Management
• /
• v.16 no.6
• /
• pp.144-155
• /
• 2015

This paper is to understand investment's efficiency and performance of commercial real estate assets diversified by use and district. To do so, this paper divides two different commercial real estate markets(office build market and retail real estate market) in Seoul city by district into "GBD(Gangnam Business District), YBD(Yeouido Business District), and CBD(Central Business District)" and "GBD(Gangnam Business District), SBD(Shinchon Business District), and CBD(Central Business District)" respectively, configures these districts each other to structure portfolios as its portion varies based on Markowitz's Mean-Variance principle, and looks at risk-return relationship of portfolios to find out efficiency, performance, and optimal investment chosen based upon Sharpe's Performance Index. As a result, the portfolio configured by "10 to 30% of office building asset at CBD" and "70 to 90% of retail real estate asset at CBD" is shown to be the most optimal, suggesting the highest quarterly Sharpe's performance index of 2.7118~2.7776 with quarterly rate of return of 1.826%~1.838% and quarterly standard deviation of 0.573~0.589. Furthermore, it is obvious that diversified portfolio configured by use(office-retail) shows better investment performance than that by district with same type of asset(office-office or retail-retail). Finally, results driven from this research will play an important role to stimulate real estate and construction markets through enlarging ideas as to diversified investment by use and district on real estate indirect investment products.