• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.30 no.3 s.47
• /
• pp.369-375
• /
• 2004

In this study, liquid crystalline (LC) is formed using Gemini surfactant (GS) type and moisturizing effect in vivo is measured. $3.0\;wt\%$ of sodium dicocoyl ethylene diamine (PEG)-15 sulfate (SCD-PEG-15S) is used as GS and $4.0\;wt\%$ of hydrogenated dimer acid esters (HDAE) as booster. For stabilizers, $2.0\;wt\%$ of behenyl alcohol (BA) and $1.0\;wt\%$ of Iyso-lecithin (LyL) are utilized. It is stabilized in pH from 4.0 to 10.5 and the best condition is in pH 6.5. The value of viscosity is $8,000\pm500$ cP. The most excellent particles are formed within the range of 4.0 to 15.5 um. Formed LC is observed around LC particles using polarization microscope. It is also observed that lamellar gel network structure is formed around LC particles. Moisturizing effect is improved by $13.6\%$ (P<0.05) compared to control when measured 30 min later after coating samples. After 1 h, moisturizing effect is improved by 1$12.6\%$ (P<0.05) than control while showing $28.3\%$ (P<0.05) of improvement after 4 h. These results may be caused from that manufactured LC forms lamellar structure so that it has better water-holding ability and absorbance of oil increases. This formula could be utilized by delivery system (DS) on skin so that this technology can be applied for manufactuing pharmaceuticals and cosmetics.

• Journal of Radiation Protection and Research
• /
• v.36 no.3
• /
• pp.127-133
• /
• 2011

In 2007, the International Commission on Radiological Protection (ICRP) published Recommendations of the International Commission on Radiological Protection. Accordingly IAEA safety standards committees have reviewed and revised the BSS. The process of the implementation of the ICRP 103 into Korean radiation protection regulations has been continued. Although the new recommendations retain the fundamental protection principles, the impact of the new ICRP recommendations will necessarily be greater than ever before. ICRP recommends the application of dose constraint in planned situations and reference level in existing & emergency situations for strengthening of the principle of optimization. Dose constraints and reference level play a criterion on the level of individual dose as prospective and source-related values. Therefore it is necessary to apply dose constraints and reference levels to all nuclear and RI&RG facilities in Rep. of Korea. Dose constraints and reference level of occupational exposure will be set-up by the stakeholder itself with the cooperation of regulatory body. In this study, the implementation method was discussed to apply the dose constraints and reference level as the procedure for the optimization, not the tool of the regulation.

• Journal of Korea Port Economic Association
• /
• v.29 no.3
• /
• pp.159-174
• /
• 2013

This paper mainly deals with the appropriation of ship voyage allocation, using a heuristic regression model, in order to reduce total costs incurred in port, yard and at sea under the specific port condition. Because of different behavior of costs incurred in port, yard and at sea, an effort to minimize these costs by adjusting the number of voyages for three ship classes(50,000, 100,000, and 150,000-ton) should be made. For instance, if the port managers attempt to reduce the sea transport cost by increasing the annual allocated number of ship voyages classed 150,000-ton for economies of scale, they have no choice but to suffer a significant increase in queueing cost due to port congestion. To put it differently, there are trade-off relationships among the costs incurred in port, yard, and at sea. We utilized a computer simulation result to perform a couple of regression analyses in order to figure out the appropriate range of allocated number of voyages of each ship class using a heuristic approach. The detailed analytical results will be shown at the main paper. We also suggested a net present value(NPV) model to make a proper investment decision for an additional berth of 200,000-ton class that alleviates port congestion and reduces transport cost incurred both in port and at sea.

• Journal of the Korean Vacuum Society
• /
• v.19 no.4
• /
• pp.249-255
• /
• 2010

Methods of the characteristics evaluation of turbo-molecular pumps (TMP) are well-defined in the international measurement standards such as ISO, PNEUROP, DIN, JIS, and AVS. The Vacuum Center in the Korea Research Institute of Standards and Science (KRISS) has recently designed, constructed, and established the integrated characteristics evaluation system of TMPs based on the international documents by continuously pursuing and acquiring the reliable international credibility through measurement perfection. The measurement of TMP pumping speed is normally performed with the throughput and orifice methods dependent on the mass flow regions. However, in the UHV range of the molecular flow region, the high uncertainties of the gauges, mass flow rates, and conductance are too critical to precisely accumulate reliable data. In order to solve the uncertainty problems of pumping speeds in the UHV range, we introduced a SRG with 1% accuracy and a constant volume flow meter (CVFM) to measure the finite mass flow rates down to $10^{-1}$ Pa-L/s with 3% uncertainty for the throughput method. In this way we have performed the measurement of pumping speed down to $10^{-4}$ Pa with an uncertainty of less than 6% for a 1000 L/s TMP. In this article we suggest that the CVFM has an ability to measure the conductance of the orifice experimentally with flowing the known mass through the orifice chambers, so that we may overcome the discontinuity problem encountering during introducing two measurement methods in one pumping speed evaluation sequence.

• Journal of Intelligence and Information Systems
• /
• v.9 no.3
• /
• pp.137-153
• /
• 2003

Comparison shopping is the most popular functionality in the e-Marketplace. Most of their revenue has been generated kent the Internet advertisement, but the ad earning was declined as the ad costing per action method widespread. Seller less familiar to the customer shrinks from chances for advertising and exposing their products. So, we need an efficient methodology subject to the seller's ad budget and other constraints, and it also has to increase comparison broker's earning in the e-Marketplace. Our research proposed and developed an ad planning methodology using comparison challenge approach which can be applied by 3$^{rd}$ party comparison brokers. Comparison challenge planning is organized with challenge policy of competitor level, product level and specification level. With that policies and basic challenge propositions, we measure the quantified value of functional distance between the specifications of my product and competitor's product. My product challenges the comparison using the comparative ad format to the similar but inferior competitor's product based on quantified valuation. Comparison challenge planning system has two phases of comparative value generation and optimization. We developed a prototype system and applied it to the desktop PC market of five major manufacturers. Our performance was emphasized by comparing to other comparative ad methods such as random display method and minimum distance method..

• Journal of Intelligence and Information Systems
• /
• v.15 no.2
• /
• pp.15-31
• /
• 2009

The next generation IT environment is expected to be an open computing environment based on Grid computing technologies, which allow users to access to any type of computing resources through networks. The open computing environment has benefits in aspects of resource utilization, collaboration, flexibility and cost reduction. Due to the variation in performance of open computing resources, however, resource allocation simply based on users' budget and time constraints often fails to meet the Service Level Agreement(SLA). This paper proposes the Mean-Absolute Deviation(MAD) portfolio optimization approach, in which service brokers consider the uncertainty of performance of resources, and compose resource portfolios that minimize the uncertainty. In order to investigate the effect of this approach, we simulate an open computing environment with varying uncertainty levels, users' constraints, and brokers' optimization strategies. The simulation result concludes threefolds. First, the MAD portfolio optimization improves the success ratio of delivering the required performance to users. Second, the success ratio depends on the accuracy in predicting the variability of performance. Thirdly, the measured variability can also help service brokers expand their service to cost-critical users by discounting the access cost of open computing resources.

• Economic and Environmental Geology
• /
• v.50 no.3
• /
• pp.239-250
• /
• 2017

Physically based landslide susceptibility analysis has been recognized as an effective analysis method because it can consider the mechanism of landslide occurrence. The physically based analysis used the slope geometry and geotechnical properties of slope materials as input. However, when the physically based approach is adopted in regional scale area, the uncertainties were involved in the analysis procedure due to spatial variation and complex geological conditions, which causes inaccurate analysis results. Therefore, probabilistic method have been used to quantify these uncertainties. However, the uncertainties caused by lack of information are not dealt with the probabilistic analysis. Therefore, fuzzy set theory was adopted in this study because the fuzzy set theory is more effective to deal with uncertainties caused by lack of information. In addition, the vertex method and Monte Carlo simulation are coupled with the fuzzy approach. The proposed approach was used to evaluate the landslide susceptibility for a regional study area. In order to compare the analysis results of the proposed approach, Monte Carlo simulation as the probabilistic analysis and the deterministic analysis are used to analyze the landslide susceptibility for same study area. We found that Fuzzy Monte Carlo simulation showed the better prediction accuracy than the probabilistic analysis and the deterministic analysis.

• Journal of Intelligence and Information Systems
• /
• v.14 no.1
• /
• pp.117-129
• /
• 2008

The cost-based scheduling work has been done in both the Operations Research (OR) and Artificial Intelligence (AI) literature. To deal with more realistic problems, AI-based heuristic scheduling approach with non-regular performance measures has been studied. However, there has been little research effort to develop a full inter-job cost propagation algorithm (CPA) for different jobs having multiple downstream and upstream activities. Without such a CPA, decision-making in scheduling heuristics relies upon local, incomplete cost information, resulting in poor schedule performance from the overall cost minimizing objective. For such a purpose, we need two types of CPAs : intra-job CPA and inter-job CPA. Whenever there is a change in cost information of an activity in a job in the process of scheduling, the intra-job CPA updates cost curves of other activities connected through temporal constraints within the same job. The inter-job CPA extends cost propagation into other jobs connected through precedence relationships. By utilizing the cost information provided by CPAs, we propose cost-based scheduling heuristics that attempt to minimize the total schedule cost. This paper develops inter-job CPAs that create and update cost curves of each activity in each search state, and propagate cost information throughout a whole network of temporal constraints. Also we propose various cost-based scheduling heuristics that attempt to minimize the total schedule cost by utilizing the cost propagation algorithm.

• Journal of Navigation and Port Research
• /
• v.39 no.6
• /
• pp.465-472
• /
• 2015

SEEMP (Ship Energy Efficiency Management Plan) guidelines for a ship's GHG reduction include a machinery modification of hull, an installation of energy efficiency enhanced attachment in hardware methods. It is also possible to bring a ship energy efficiency improvement by fuel-efficient operations or in other software methods. Hardware modification or installation on ship can bring financial burdens to a ship company compared to its improvement expectation. On the other hand, Software based energy-saving technology can be applicable on various ship types, and it is also expected high efficiency of ship energy use compared to hardware based technology in perspective of the investment costs and efficiency. In this paper, it is described that the ship handling simulator based evaluation was carried out using representative ship model of bulk, container and VLCC. Simulation environments were separated into 6 conditions according to the sea-state and weather condition, and the operation results were compared with those before and after energy saving system applied The container ship showed the largest FOC save rate after energy saving system applied although the others also showed energy save rate after using the system.

• Journal of KIISE
• /
• v.42 no.5
• /
• pp.629-636
• /
• 2015

The types of errors corrected by a Korean spelling and grammar checker can be classified into isolated-term spelling errors and context-sensitive spelling errors (CSSE). CSSEs are difficult to detect and to correct, since they are correct words when examined alone. Thus, they can be corrected only by considering the semantic and syntactic relations to their context. CSSEs, which are frequently made even by expert wiriters, significantly affect the reliability of spelling and grammar checkers. An existing Korean spelling and grammar checker developed by P University (KSGC 4.5) adopts hand-made correction rules for correcting CSSEs. The KSGC 4.5 is designed to obtain very high precision, which results in an extremely low recall. Our overall goal of previous works was to improve the recall without considerably lowering the precision, by generalizing CSSE correction rules that mainly depend on linguistic knowledge. A variety of rule-based methods has been proposed in previous works, and the best performance showed 95.19% of average precision and 37.56% of recall. This study thus proposes a statistics based method using a conditional probability model with dynamic window sizes. in order to further improve the recall. The proposed method obtained 97.23% of average precision and 50.50% of recall.