• Journal of the Korean Applied Science and Technology
• /
• v.31 no.1
• /
• pp.151-158
• /
• 2014

Asphaltenes are generally defined by their solubility when a light alkane, such as n-heptane or n-pentane, is mixed with crude oils or oil sand bitumen. However, this definition is nowadays not enough to understand their behaviors during oil recovery, transport, storage, and even refinery operation. Interestingly, the researches regarding asphaltenes have been vastly presented within last decade. This is because the production of heavy oils is becoming larger and asphaltenes are known to play an important role in the property changes of heavy oils. In this paper, the researches regarding molecular weight, aggregation behavior of asphaltenes are introduced and discussed. It is expected that analytical studies will be appeared continuously in the form of global collaboration in order to describe asphaltene molecules as close as possible based on their origin.

• Journal of Korean Port Research
• /
• v.12 no.1
• /
• pp.25-33
• /
• 1998

The evaluation of port competition could be applied to determining the selection of a calling port. A few fundemental attributes of port competition were adapted by the 'brain storming' method. The criteria used for evaluating a port's competitiveness were as follows: efficiency of port operations, competitive power of each port's industry, economic activity of the hinderland associated with each port and capability of globalization. The weight of each criterion was 30%, 40%, 20% & 10%, respectively. And the most important factors that were considered in choosing each of the above criteria were profitability, port information system, cargo volume & inducement of foreign capital. The results of this study seemed to suggest that factors which influence port competition varied according to port circumstances, such as computer and communication systems and access to the global trade within the World Trade Organization

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2003.10a
• /
• pp.145-152
• /
• 2003

An optimal design method in cooperated with nonlinear inelastic analysis method is presented. The proposed nonlinear inelastic method overcomes the difficulties due to incompatibility between the elastic global analysis and the limit state member design in the conventional LRFD method. The genetic algorithm uses a procedure based on Darwinian notions of survival of the fittest, where selection, crossover, and mutation operators are used among sections in the database to look for high performance ones. They satisfy the constraint functions and give the lightest weight to the structure. The objective function is set to the total weight of the steel structure and the constraint functions are load-carrying capacities, serviceability, and ductility requirement. Case studies of a three-dimensional frame and a three-dimensional steel arch bridge are presented.

• Coupled systems mechanics
• /
• v.11 no.3
• /
• pp.259-266
• /
• 2022

Non-Traditional Optimization methods are successfully used in solving many engineering problems. Shaft is one of important element of machines and it is used to transmit power from a machine which produces power to a machine which absorbs power. In this paper, ten non-traditional optimization methods that are ALO, GWO, DA, FPA, FA, WOA, CSO, PSO, BA and GSA are used to find minimum weight of hollow shaft to get global optimal solution. The problem has two design variables and two inequality constraints. The comparative results show that the Particle Swarm Optimization outperforms other methods and the results are validated using ANSYS.

• KDI Journal of Economic Policy
• /
• v.32 no.4
• /
• pp.153-195
• /
• 2010

The recent global financial crisis has been the outcome of, among other things, the mismatch between institutions and the reality of the market in the current global financial system. The International financial institutions (IFIs) that were designed more than 60 years ago can no longer effectively meet the challenges posed by the current global economy. While the global financial market has become integrated like a single market, there is no international lender of last resort or global regulatory body. There also has been a rapid shift in the weight of economic power. The share of the Group of 7 (G7) countries in global gross domestic product (GDP) fell and the share of emerging market economies increased rapidly. Therefore, the tasks facing us today are: (i) to reform the IFIs -mandate, resources, management, and governance structure; (ii) to reform the system such as the international monetary system (IMS), and regulatory framework of the global financial system; and (iii) to reform global economic governance. The main focus of this paper will be the IMS reform and the role of the Group of Twenty (G20) summit meetings. The current IMS problems can be summarized as follows. First, the demand for foreign reserve accumulation has been increasing despite the movement from fixed exchange rate regimes to floating rate regimes some 40 years ago. Second, this increasing demand for foreign reserves has been concentrated in US dollar assets, especially public securities. Third, as the IMS relies too heavily on the supply of currency issued by a center country (the US), it gives an exorbitant privilege to this country, which can issue Treasury bills at the lowest possible interest rate in the international capital market. Fourth, as a related problem, the global financial system depends too heavily on the center country's ability to maintain the stability of the value of its currency and strength of its own financial system. Fifth, international capital flows have been distorted in the current IMS, from EMEs and developing countries where the productivity of capital investment is higher, to advanced economies, especially the US, where the return to capital investment is lower. Given these problems, there have been various proposals to reform the current IMS. They can be grouped into two: demand-side and supply-side reform. The key in the former is how to reduce the widespread strong demand for foreign reserve holdings among EMEs. There have been several proposals to reduce the self-insurance motivation. They include third-party insurance and the expansion of the opportunity to borrow from a global and regional reserve pool, or access to global lender of last resort (or something similar). However, the first option would be too costly. That leads us to the second option - building a stronger globalfinancial safety net. Discussions on supply-side reform of the IMS focus on how to diversify the supply of international reserve currency. The proposals include moving to a multiple currency system; increased allocation and wider use of special drawing rights (SDR); and creating a new global reserve currency. A key question is whether diversification should be encouraged among suitable existing currencies, or if it should be sought more with global reserve assets, acting as a complement or even substitute to existing ones. Each proposal has its pros and cons; they also face trade-offs between desirability and political feasibility. The transition would require close collaboration among the major players. This should include efforts at the least to strengthen policy coordination and collaboration among the major economies, and to reform the IMF to make it a more effective institution for bilateral and multilateral surveillance and as an international lender of last resort. The success on both fronts depends heavily on global economic governance reform and the role of the G20. The challenge is how to make the G20 effective. Without institutional innovations within the G20, there is a high risk that its summits will follow the path of previous summit meetings, such as G7/G8.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.16 no.2
• /
• pp.51-51
• /
• 1991

Recently financial institutions in Korea are experiencing an unfamiliar challenge in terms of their operational risk management due to the volatility of global financial market and the incessant development of new financial products. In this paper, we present an AHP(Analytic Hierarchy Process) model to evaluate the effectiveness of commercial softwares for risk management in banking. The AHP model considers software's performance. utility, serviceability and durability as major evaluation criteria. The weight of each criterion is generated by the questionnaire survey given to practitioners in risk management in domestic commercial banks.

• Korean Management Science Review
• /
• v.16 no.2
• /
• pp.51-59
• /
• 1999

Recently financial institutions in Korea are experiencing an unfamiliar challenge in terms of their operational risk management due to the volatility of global financial market and the incessant development of new financial products. In this paper, we present an AHP(Analytic Hierarchy Process) model to evaluate the effectiveness of commercial softwares for risk management in banking. The AHP model considers software's performance. utility, serviceability and durability as major evaluation criteria. The weight of each criterion is generated by the questionnaire survey given to practitioners in risk management in domestic commercial banks.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 1993.06a
• /
• pp.1017-1020
• /
• 1993

This paper describes a neo fuzzy neuron which was produced by a fusion of fuzzy logic and neuroscience. Some learning algorithms are presented. The guarantee for the global minimum on the error-weight space is proved by a reduction to absurdity. Enhanced is that the learning speed of the neo fuzzy neuron exceeds 100,000 times of that of conventional multi-layer neural networks.

• Proceedings of the KSR Conference
• /
• 1998.11a
• /
• pp.583-588
• /
• 1998

Large extrusions of aluminium alloy can be more general and useful as structural material of rolling stocks to reduce weight and labor cost than mild steel and stainless steel. Our company is studying aluminium coach body will be made of 6005A and A5083 alloy. In this paper, at first detailed finite element analysis is carried out to calculate the orthotropic material properties of aluminium extrusions. And then global strength evaluation of coach body is carried out according to UIC 566 OR code.

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.160.1-160.1
• /
• 2003

Persistent organic pollutants (POPs) have spread throughout the global environment to threaten human health and damage ecosystems. with evidence of POPs contamination in wildlife, human blood. and breast milk documented worldwide. Breast milk is an ideal medium for assessing exposures to POPs. POPs enter humans largely as contaminants of dietary animal products, where they sequester in adipose tissue, serum, and breast milk and equilibrate at similar levels on a fat weight basis. (omitted)