• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.15 no.2
• /
• pp.151-160
• /
• 2011

Typically, it is hard to find a closed form solution of option pricing formula under an asset governed by a change point process. In this paper we derive a closed-form solution of the valuation function for an American perpetual put option under an asset having a change point. Structural changes are formulated through a change-point process with a Markov chain. The modified smooth-fit technique is used to obtain the closed-form valuation function. We also guarantee the optimality of the solution via the proof of a corresponding verification theorem. Numerical examples are included to illustrate the results.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.16 no.12
• /
• pp.1183-1189
• /
• 2004

An experimental investigation is conducted to measure phase change temperature and supercooling when acetone is added to TMA 30 wt% clathrate during cooling process in heat source. Also rate of volume change is investigated when acetone is added to TMA 30 wt% clathrate during the cooling process in heat source -8$^{\circ}C$. The results show that phase change temperature is about 4.5～5.5$^{\circ}C$ when acetone is added to TMA 30 wt% clathrate during the cooling process for heat sink temperature of -6, -7$^{\circ}C$ and -8$^{\circ}C$. Supercooling is repressed about 2～1$0^{\circ}C$ when 0.08 wt% acetone is added to it and rate of volume change is decreased about 2.9% when 0.1 wt% acetone is added for the heat sink temperature of -8$^{\circ}C$.

• Journal of Industrial Technology
• /
• v.25 no.B
• /
• pp.107-114
• /
• 2005

Digital media was realized by two-dimensional design backup. But, digital medium decides form of architecture, and act as a design tool that can expand area of thinking. With such social change, investigate for digital architecture. And, wish to analyze design process of digital architecture and search the characteristics. Through comparison of digital and analogue, clear up that the digital world had complex and ambivalent attribute. Define digital design process as "Digital continuum" with characteristic of digital architecture and divided in 3-steps of concept - development - representation. Analyzed digital design process of Frank O, Ghery, Peter Eisenman and Greg Lynn on th assumption division. As a result, design concept is starting from three-dimensional thinking instead of existent two-dimensional thinking. And because general work of process was gone by digital media, "mass costomization" was possible. Also, it gave architect new role. Differ with former days, select various variables, should tuning and cording, and emphasize role as coordinator who must select the result. Digital is summoning very radical and epoch-making change in architecture. At center of these change, digital design process asks architect complex thinking and creative concept.

• Korean System Dynamics Review
• /
• v.16 no.2
• /
• pp.75-100
• /
• 2015

The purpose of this study is to analyze causation of Ecosystem service's trade-off(ES trade-off) and to establish baseline data for wise spatial planning and management. In order to understand why and how ES trade-off occurs, systems thinking and causal loops were employed. The causal loop of ecosystem service creation cycle includes profits quantification process, decision making process, spatial planning and management process, and ecosystem services creation process. The profits quantification process has a limitation that all ecosystem service categories were not included in profits quantification, because quantification method for cultural services is insufficient. These problems led to unequal discussion opportunity in decision making process. ES trade-off occurs through transition of ecosystem function in spatial scale and temporal scale. In spatial scale, land-use variation and resource-use variation contribute to change an ecosystem function for different ES category by spatial planning and management. In temporal scale, a change of an ecosystem function for different ES category is influenced by ecological succession, seasonal change and land cover variation, which are parameter from environmental features. This study presented that spatial planning and management should ecosystem service assessment in order to enhance balanced ecosystem services.

• Journal of Korean Academy of Nursing
• /
• v.33 no.8
• /
• pp.1171-1177
• /
• 2003

Purpose. Despite many smoking cessation programs, many patients with CAD continue to smoke or re-smoke. The processes of change and self-change for smoking cessation is emphasized. The purpose of present study was to investigate decisional balances and processes of change according to stages of change for smoking cessation in the patients with CAD. Methods. This descriptive study was performed using the self-reported questionnaires from 157 male patients with CAD who have smoking experiences. The questionnaires consisted of decisional balances toward smoking (pros/cons) and processes of change including 7 factors. Results. 45.2% of the subjects had myocardial infarction and 54.8% for angina pectoris. Major stages of change were maintenance, contemplation, and precontemplation in 62%, 14%, and 18% respectively. The mean score of pros smoking was 31.07 and cons smoking was 32.52. The mean scores of processes of change were high in all 7 factors, especially in self determination. The pros smoking in precontemplation stage was significantly higher than those in other stages. Between contemplation and precontemplation stages, processes of change showed significant differences in stimulus control, self determination, information management, and dramatic relief. Conclusion. This study suggests that decisional balances and processes of change are stage-specific. As this study, smoking cessation program in the patients with CAD must put priority on the patients group in pre-contemplation and contemplation stages, and stress self determination and dramatic relief.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2005.05a
• /
• pp.723-729
• /
• 2005

Traditional statistical process control(SPC) applied to discrete part industry in the form of control charts can look for and eliminate assignable causes by process monitoring. On the other hand, engineering process control(EPC) applied to the process industry in the form of feedback control can maintain the process output on the target by continual adjustment of input variable. This study presents controlling and monitoring rules adopted variable sampling interval(VSI) to change sampling intervals in a predetermined fashion on the predicted process levels for integrated EPC and SPC systems. Twelve rules classified by EPC schemes(MMSE, constrained PI, bounded or deadband adjustment policy) and type of sampling interval combined with EWMA chart of SPC are proposed under IMA(1,1) disturbance model and zero-order (responsive) dynamic system. The properties of twelve control rules under three patterns of process change(sudden shift, drift and random shift) are evaluated and discussed through simulation and control rules for integrated VSI EPC and SPC systems are recommended.

• Management Science and Financial Engineering
• /
• v.9 no.2
• /
• pp.21-45
• /
• 2003

Various organizational factors effect successful implementation of IT enabled business transformation. Among them, the most critical success factor is deemed to overcoming change management problem. Lots of studies have been made on implementation methodologies and business process formalizations to encourage organizational members to accept new business process changes. However, the logic of process redesign still depends on qualitative problem solving techniques mostly depending on basically human intuition such as brainstorming, cause-and-effect analysis, and so on. In this paper, we develop algorithmic procedure applicable to designing various business process changes such as process automation, business process resequencing, and more radical process integration. The framework is employed from dynamic programming approach in the literature, which is based on the decision making paradigm of organizations to abstract business processes as quantitative decision models. As such, our research can fill the gap of limited development of theory based analytic methodologies for business process design, by providing objective rationale to reach the consensus among the organizational members including senior management.

• Journal of the Korean Ceramic Society
• /
• v.52 no.2
• /
• pp.133-136
• /
• 2015

The outward diffusion of $Na^+$ ions in iron-bearing soda lime silicate glass via oxidation heat treatment before the ion exchange process is artificially induced in order to increase the amount of ions exchanged during the ion exchange process. The effect of the addition process is analyzed through measuring the bending strength, the weight change, and the inter-diffusion coefficient after the ion exchange process. The glass strength is increased when the outward diffusion of $Na^+$ ions via oxidation heat treatment before the ion exchange process is added. For the glass subjected to the additional process, the weight change and diffusion depth increase compared with the glass not subjected to the process. The interdiffusion coefficient is also slightly increased as a result of the additional process.

• 제어로봇시스템학회:학술대회논문집
• /
• 1993.10b
• /
• pp.132-137
• /
• 1993

In this paper, a fish drying process control system is proposed, which predicts the proper change with time in weight of the material fish and the drying conditions in advance, based on the performance of skilled worker. In order to implement a human expertise into an automated fish drying process control system, an experimental analysis is made and a model for the process is built. The proposed system divided into two procedures: The procedure before drying and the one during drying. The procedure before drying is for the prediction of necessary drying time. To estimate the necessary drying time, first, the proper change in weight for the product is obtained by using fuzzy reasoning. The condition part of the production rule consists of the factors of fish body and the expected degree of dryness. Kext, the necessary drying time is obtained by regression models. The variables employed in the models are the factors, inferred change in weight and drying conditions. The model for the procedure during drying is also proposed for more accurate estimation, which is described by a system of linear-differential equations.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2004.05a
• /
• pp.139-142
• /
• 2004

Nickel base superalloys are widely used for high temperature applications due to heat resisting capability and corrosion resistance at high temperatures. Superalloys with many strengthening alloying elements are frequently used in powder form to alleviate harmful effects of alloy segregation. HIP (hot isostatic pressing) and DB (diffusion bonding) as a form of solid-state bonding process is used to make turbine components, such as integrated turbine rotors. HIP/DB process requires many technical overcomes related to dimensional changes as well as microstructural control. In this research, HIP/DB process for nickel base superalloys, Udimet 720 and MM 247, were investigated with a view to control the dimensional change during the consolidation process. Simple disc-shaped cans were used to select the conceptual die design for the control of the dimensional change especially in radial direction. The change in the shape of consolidated shape was investigated using commercial FE code with constitutive equations fur low temperature plasticity deformation.