• KSBB Journal
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• v.24 no.3
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• pp.312-320
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• 2009

Stable cell preservation is an essential factor in the regenerative medicine for cell therapies and transplantation of biologic materials. In this study, we studied to provide more stable hypothermic preservation by protection of cell damage during the preservation at $4^{\circ}C$. The result of searching for key components that have excellent efficacy in hypothermic preservation of cells, we have identified the fact that the hypothermic preservation adding protein hydrolysates such as yeast hydrolysate is far superior to others. All protein hydrolysates that are derived from animal, plant and microbe sources have superior efficacy, especially the peptides which have molecular weights under 10 kDa have the best efficacy among the components of protein hydrolysate. The protein hydrolysates prevented the decrease of ATP level in the cells caused by hypothermic environment and they inhibited the generation of ROS. Adding antioxidants and control agents of osmotic pressure were showed to have more superior efficacy in hypothermic preservation. Finally, KUL261 solution (DMEM/F12 1 : 1 medium, yeastolate 1%, $\alpha$-tocopherol $100{\mu}M$, dextran 2.5%), the preservation solution developed in this study, showed the best efficacy in both cell viability and cell growth more than other conventional preservation solutions. In conclusion, the improved hypothermic preservation solution that contains the protein hydrolysates as a key component provide the best preservation efficacy. It provides better efficacy than other preservation solutions and will contribute to both the development of regenerative medicine and global commercialization in this therapeutic field.

• Analyses & Alternatives
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• v.3 no.1
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• pp.29-61
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• 2019

Within the discipline of International Relations (IR), the literatures on global governance (GG) and great power management (GPM) at best ignore each other, and at worst treat the other as a rival or enemy. On the one hand, the GPM literature, like both realism in all its forms, and neoliberalism, takes for granted the ongoing, disproportionate influence of the great powers in the management of the international system/society, and does not look much beyond that. On the other hand, the GG literature emphasizes the roles of smaller states, non-state actors and intergovernmental organizations (IGOs), and tends to see great powers more as part of the problem than as part of the solution. This paper argues that the rise to prominence of a non-traditional security agenda, and particularly of human security, has triggered a de facto merger of GPM and GG that the IR literature usually treated as separate and often opposed theories. We use the Ebola crisis of 2014-15 to show how an issue framed as human security brought about a multi-actor response that combined the key elements of GPM and GG. The security framing overrode many of the usual inhibitions between great powers and non-state actors in humanitarian crises, including even the involvement of great power military forces. Through examining broadly the way in which the Ebola crisis is tackled, we argue that in an age of growing human security challenges, GPM and GG are necessarily and fruitfully merging. The role of great powers in this new human security environment is moving away from the simple means and ends of traditional GPM. Now, great powers require the ability to cooperate and coordinate with multiple-level actors to make the GG/GPM nexus more effective and sustainable. In doing so they can both provide crucial resources quickly, and earn respect and status as responsible great powers. IGOs provide legitimation and coordination to the GPM/GG package, and non-state actors (NSAs) provide information, specialist knowledge and personnel, and links into public engagement. In this way, the unique features of the Ebola crisis provide a model for how the merger of GPM and GG might be taken forward on other shared-fate threats facing global international society.

• Smart Structures and Systems
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• v.25 no.4
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• pp.487-499
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• 2020

This paper proposes a novel approach to model updating for a large-scale cable-stayed bridge based on ambient vibration tests coupled with a hybrid metaheuristic search algorithm. Vibration measurements are carried out under excitation sources of passing vehicles and wind. Based on the measured structural dynamic characteristics, a finite element (FE) model is updated. For long-span bridges, ambient vibration test (AVT) is the most effective vibration testing technique because ambient excitation is freely available, whereas a forced vibration test (FVT) requires considerable efforts to install actuators such as shakers to produce measurable responses. Particle swarm optimization (PSO) is a famous metaheuristic algorithm applied successfully in numerous fields over the last decades. However, PSO has big drawbacks that may decrease its efficiency in tackling the optimization problems. A possible drawback of PSO is premature convergence leading to low convergence level, particularly in complicated multi-peak search issues. On the other hand, PSO not only depends crucially on the quality of initial populations, but also it is impossible to improve the quality of new generations. If the positions of initial particles are far from the global best, it may be difficult to seek the best solution. To overcome the drawbacks of PSO, we propose a hybrid algorithm combining GA with an improved PSO (HGAIPSO). Two striking characteristics of HGAIPSO are briefly described as follows: (1) because of possessing crossover and mutation operators, GA is applied to generate the initial elite populations and (2) those populations are then employed to seek the best solution based on the global search capacity of IPSO that can tackle the problem of premature convergence of PSO. The results show that HGAIPSO not only identifies uncertain parameters of the considered bridge accurately, but also outperforms than PSO, improved PSO (IPSO), and a combination of GA and PSO (HGAPSO) in terms of convergence level and accuracy.

• Journal of The Korean Digital Architecture Interior Association
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• v.5 no.1
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• pp.9-16
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• 2005

In Interior design, light is the most important factor in deciding color, texture and illumination level which are the basic factors of spatial design. To apply rendering technologies on prediction of illuminating effect, it is important to understand and analyse the basic properties of the illumination models that are local illumination model and global illumination model. The illumination models in computer graphics express the factors which determine the surface color, texture and light distribution through the reflection. The purpose of this study is to propose the best way of shading algorithm in interior space provided by the computer, based on the experimental analysis that 5 shading methods are applied to the interior space. The results of this study were as followed. 1) Local illumination models that are Lambert shading, Ground shading and Phong shading are not suitable to the prediction of interior illumination effect. 2) Ray tracing that is global illumination model could be adopted to interior illumination effects. Ray tracing is a very versatile algorithm because of the large range of lighting effects it can model. 3) Neither radiality nor ray tracing offers a complete solution for simulating all interior illumination effects. 4) Radiosity excels at rendering diffuse-to-diffuse inter-reflections and ray tracing excels at rendering specular reflections. By merging both shading techniques, that offers the best of both. Using computer technologies to simulate lighting in preliminary design stage which will provide information for designers and occupants to determine the effect of using artificial light sources at each stage of their design process. Further study in illumination analysis, prediction of illumination effect, and lighting calculation is required as computer media expands.

• International Journal of Fluid Machinery and Systems
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• v.10 no.3
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• pp.240-253
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• 2017

Latin hypercube sampling is widely used design-of-experiment technique to select design points for simulation which are then used to construct a surrogate model. The exploration/exploitation properties of surrogate models depend on the size and distribution of design points in the chosen design space. The present study aimed at evaluating the performance characteristics of various surrogate models depending on the Latin hypercube sampling (LHS) procedure (sample size and spatial distribution) for a diverse set of optimization problems. The analysis was carried out for two types of problems: (1) thermal-fluid design problems (optimizations of convergent-divergent micromixer coupled with pulsatile flow and boot-shaped ribs), and (2) analytical test functions (six-hump camel back, Branin-Hoo, Hartman 3, and Hartman 6 functions). The three surrogate models, namely, response surface approximation, Kriging, and radial basis neural networks were tested. The important findings are illustrated using Box-plots. The surrogate models were analyzed in terms of global exploration (accuracy over the domain space) and local exploitation (ease of finding the global optimum point). Radial basis neural networks showed the best overall performance in global exploration characteristics as well as tendency to find the approximate optimal solution for the majority of tested problems. To build a surrogate model, it is recommended to use an initial sample size equal to 15 times the number of design variables. The study will provide useful guidelines on the effect of initial sample size and distribution on surrogate construction and subsequent optimization using LHS sampling plan.

• Journal of English Language & Literature
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• v.58 no.5
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• pp.943-974
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• 2012

This paper aims to suggest the compromising vision of nature and technology as the solution to get out of the globally accelerated technology environment in Don DeLillo's Cosmopolis. This novel intends to emphasize on the importance of physical environment as a precondition for the survival of human. Eric wants to be a posthuman with the cybernetic idea, pursuing to be the digital self in a vast biosphere that integrates both the nature and the technology. His obsessive worship of technology through his quest for the futurity results in the effacement of the humanity and the insulation from the nature. Cosmopolis is DeLillo's first 9/11 novel, which describes a young-billionaire asset manager Eric's one-day life in New York in April 2000. Eric can be the third Twin Tower as a symbol of global economic hegemony. By the allusion of the 9/11 catastrophic event, it can be said that Eric's fall is caused by his hubris and avarice as a global capitalist. Crossing the 47th Street toward the West in his limousine, his journey is revealed as the environmental reflections on his desires to attain the futurity and transcendence by technology. This novel cautions that the abuse of technology can bring out the obsolescence and erasure of the humanity and the nature. DeLillo suggests that the best hope for the evolutionary possibility of posthuman can be realized through the correlation with nature and technology. This future-oriented novel warns that the excessive technology should not lead to the disappearance of community and humanity, and the separation of self and nature. It admonishes that they should not follow pseudo-cosmopolitanism as the greedy world citizens, devoting on the velocity of newest technology. This novel recommends that humans should be the world citizen of global ecosystem, making the ameliorative environment through the correlation with self/environment and technology/nature, and gardening the restorative biosphere and the younger planet.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.3
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• pp.1016-1022
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• 2010

An Experimental study of cleaning solution has been performed on a high capacity steam boiler burning heavy fuel oil to on-line cleaning of deposit. The deposit is mixture of soot, slag, ash, metal oxide and clinker. The traditional technology of deposit cleaning was carried hand-crafted. The conventional technology of boiler cleaning method is mechanical removal by the worker while the boiler shut down operation. In this experiment, the deposit of mixture of soot, slag, ash, metal oxide and clinker has been removed by the cleaning agents without shut down of boiler burning. This study found out the optimum cleaning solution composition. The best results have been obtained when the mixture of ammonium nitrate and $MgNO_3$ were used in cleaning solution. The various transition metal effect was investigated for optimum mixing condition. In this research, the metal compound additive of the clean solution compoition was obtained. The combustion efficiency was improved by on-line cleaning with derived clean solution compoition. On-line cleaning method prevents the fouling and corrosion in the boiler and heat exchanger.

• Korean Journal of Computational Design and Engineering
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• v.16 no.4
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• pp.260-267
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• 2011

Nowadays, automobile manufacturers are faced with increasing global competition which is required low cost as well as high quality. To reduce shipping and handling cost and delivery time, lots of automobile manufactures tried to build their new factory in the neighborhood of market. Simultaneously, many factories are under construction in developing countries to make efficient use of low-wage workers. However, because systems are installed in developing countries as the same type of domestic facilities, systems have lots of problems such as high installation cost and inefficient use of manpower. To find core problems and generate optimal solution of these problems, thinking process of TOC(Theory Of Constrains) is used. In case of transmission gear machining system, semi-auto system is proposed as the best solution to increase manpower efficiency and system utilization. Semi-auto system consists of automatic machining process and manual transporting process. The system layout is generated based on semi-auto process concept. And, 3D simulation method using QUEST is used to verify production volume of generated system.

• Journal of Ocean Engineering and Technology
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• v.18 no.5
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• pp.29-35
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• 2004

A new approach, referred to as a successive zooming genetic algorithm (SZGA), is proposed for identifying a global solution, using continuous zooming factors for optimization problems. In order to improve the local fine-tuning of the GA, we introduced a new method whereby the search space is zoomed around the design variable with the best fitness per 100 generation, resulting in an improvement of the convergence. Furthermore, the reliability of the optimized solution is determined based on the theory of probability, and the parameter used for the successive zooming method is optimized. With parameter optimization, we can eliminate the time allocated for deciding parameters used in SZGA. To demonstrate the superiority of the proposed theory, we tested for the minimization of a multiple function, as well as simple functions. After testing, we applied the parameter optimization to a truss problem and wicket gate servomotor optimization. Then, the proposed algorithm identifies a more exact optimum value than the standard genetic algorithm.

• IEIE Transactions on Smart Processing and Computing
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• v.2 no.6
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• pp.350-356
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• 2013

Single Carrier Frequency Domain Multiple Access (SC-FDMA) has proven to be the best long term evolution for uplink multiple access because of its low Peak to Average Power Ratio (PAPR), a feature that leads to low power consumption. This is achievable only if the resource allocation is performed in a contiguous manner. This paper proposes a new approach with an improvement in the global resources allocation. The new approach presented utilizes the gain function, which adopts some of the procedures deduced from the older Recursive Maximum Expansion (RME) algorithm. The experiment proved that the new approach is better than the original RME algorithms and in most cases, is closer to the optimal solution.