• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.7
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• pp.491-499
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• 2007

An architectural means of optimal daylight distribution is by using so-called light shelf systems, horizontal shading and redirecting devices. The overall performance of the daylighting system can be improved by the incorporation with electric lighting control devices. This paper aims to exemplify the benefit of daylighting in term of economic consideration. In such a case a reasonable technique to compare system costs is by life-cycle costing. Stated simply, a life-cycle cost represents the total cost of a system over its entire life cycle, that is, the sum of first cost and all future costs. Four different electric lighting system designs are proposed and a lighting control system that is continuously operating according to the level of daylight in the space has been adapted. The result shows clearly that although denser layout of lighting fixtures might be more effective to interface to the level of daylight ceaselessly changeable, its economic benefit may not meet the expected criterion the reason of increased initial investment and maintenance cost for the fixtures and control devices.

• Korean Journal of Clinical Pharmacy
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• v.18 no.1
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• pp.28-37
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• 2008

Objectives: Overactive bladder(OAB), defined as 'urgency, with or without urge incontinence, usually with frequency and nocturia', is a major burden for patients and impairs quality of life. The aim of this study is to evaluate the cost-effectiveness of antimuscarinic agents for the treatment of overactive bladder including quality of life in societal perspective. Methods: A decision-analysis model was developed to compare the cost-effectiveness of solifenacin and tolterodine IR over 12 weeks. We used data from the published literature to develop the framework for the model. Resource utilization and costs were calculated with public institutional data and supplemented this information with clinical expert opinion, where necessary. Results: The expected costs per patient for solifenacin were 48,762 KRW less expensive than tolterodine IR over 12 weeks. Also, all outcomes including quality of life for solifenacin were more effective than tolterodine IR over 12 weeks. In conclusion, solifenacin dominates tolterodine IR and appears to be cost-effective options for the management of overactive bladder.

• KIEAE Journal
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• v.6 no.3
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• pp.11-18
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• 2006

Attention on daylighting should be focused not so much on a simple maximization of the natural light available in a space, as on improving the quality of lighting by ensuring as even but intense distribution of illumination in inner areas. An architectural means of optimal daylight distribution is by using so-called light shelf systems, horizontal shading and redirecting devices. The overall performance of the daylighting system can be improved by the incorporation with electric lighting control devices. This paper aims to exemplify the benefit of daylighting in term of economic consideration. In such a case a reasonable technique to compare system costs is by life-cycle costing. Stated simply, a life-cycle cost represents the total cost of a system over its entire life cycle, that is, the sum of first cost and all future costs. Four different electric lighting system designs are proposed and a lighting control system that is continuously operating according to the level of daylight in the space has been adapted. The result shows clearly that although denser layout of lighting fixtures might be more effective to interface to the level of daylight ceaselessly changeable, its economic benefit may not meet the expected criterion the reason of increased initial investment and maintenance cost for the fixtures and control devices.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.724-726
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• 1996

In this paper, we propose an optimal daily operation model for the total energy system which includes cogeneration, thermal storage and electrical charger and ice storage facilities. Storing and utilizing the surplus thermal and electrical energy, the daily operation cost could be reduced and more efficient use of thermal energy could be achieved. The ice storage cooling system has a merit of reduce the electricity cost by time of day rate(peak/off-peak). And also, refrigerator can be down sized compare to the other cooling system From this model, operation costs of the sample cogeneration system with/without auxiliary facilities are obtained and compared to each other. In case study, the sensitivity of operating cost is simulated according to the variation of cogeneration production cost, electricity rate, etc.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2005.11a
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• pp.461-470
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• 2005

A dynamic supply chain that is composed of many different companies with different rent roles and interests allows free joining and secession. Buyers place orders simultaneously and manufacturers should compete each other for the orders. The purpose of our paper is how to find the optimal formation of supply chain ill a global viewpoint while allowing each member company to pursue his local goal The dynamic nature of supply chain formation causes the variation of cost depending on how many orders a manufacturer would accept. We propose a multi-agent based negotiation protocol that efficiently leads to the formation of optimal supply chain without giving up maximization of the individual profit in multi-agent environment of the make-to-order industry. The goal of the negotiation is to form a supply chain to minimize the overall sum of manufacturers' manufacturing cost, and earliness cost and tardiness cost based on SET model. We compare the negotiation protocol with Branch & Bound method. Finally, the validity and performance of buyer's negotiation has been tested experimentally.

• Journal of Navigation and Port Research
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• v.46 no.5
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• pp.419-426
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• 2022

This study aimed to identify new routes for transporting automobiles from Korea to Mongolia by comparing them with the existing route. At present, a route from the Incheon Port through the Tianjin Port to Zamiin-Uud is commonly used to transport containerized cargo from Korea to Mongolia. This study examined five possible logistics routes from Korea to Mongolia using a time/cost-distance methodology based on real data. Through consecutive discussions with importers and freight forwarders in Mongolia, the potential routes were selected and costs, distance, and lead time were evaluated to provide additional route options for automobile logistics from Korea to Mongolia. The results indicated that each route could be ranked in terms of the total cost while the lead time for all options in the present COVID-19 period is 2 - 4 months, with no difference among the routes. In addition, although the confidence index of all routes was not impressive, route 3 was the most preferred option, followed by route 1. However, the study results cannot provide the answer to the question of "which route is more attractive for transporting automobiles from Korea to Mongolia." This limitation notwithstanding, this study provides real information on the critical factors of distance, cost, and lead time in terms of the selected transportation routes so that importers and exporters can compare the routes in terms of the priority of each factor in uncertain logistics environment.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.494-496
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• 2013

Cost-Benefit Analysis (CBA) is a systematic optimization process that allows users to compare different alternatives and to determine if a project is a solid investment. Many state DOTs have included CBA in their pavement management systems (PMSs) to help allocate state funds for maintenance, rehabilitation, resurfacing, and reconstruction of pavements. In a typical CBA, each pavement type has an assigned weight factor which represents the level of importance of this pavement type. To conduct an accurate CBA, it is essential to select appropriate weight factors. Arbitrarily assigning weights factors to pavements can lead to biased and inaccurate funding allocation decisions. The purpose for this paper is to outline a method to develop an ideal set of weight factors that can be utilized to conduct more accurate CBA. To this end, a matrix of all possible weight factors sets was developed. CBA was conducted for each set of weight factors to obtain a population of possible optimization solutions. Then a regression analysis was performed to establish the relationship between benefit and weight factors. Finally, a multi-objective genetic algorithm was applied to select the optimal set of weight factors. The findings from this study can be used by state DOTs to strategically manage their roadway systems in a cost effective manner.

• Korean Journal of Construction Engineering and Management
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• v.23 no.5
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• pp.65-76
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• 2022

The New Excellent Technology (NET) designation system, introduced in 1989 for the purpose of promoting the development of domestic construction technology and enhancing national competitiveness, reviews the statement of construction cost of new technologies. And the cost reduction effect such as design, construction, and maintenance cost and the effect of reducing the construction duration are evaluated as an evaluation criteria of economic feasibility. However, in this evaluation process, differences of opinion between the institution of construction cost estimating standard management and the new technology developer about unique technologies frequently occur. In addition it is difficult to objectively compare the construction duration with existing similar technologies because there is no information on productivity as the current cost estimating standards for new technologies only present the required amount per unit quantity. In this study, the current state of cost estimating criteria review procedure, evaluation criteria, and cost estimating standards establishment method were analyzed when screening for the designation of a new construction technologies, and compared with overseas cost estimating standards, measures to improve the cost estimating standards of current construction new technologies were suggested. Through the improved cost estimating standards of this study, it is expected that cost information on new technologies will be provided to clients in more detail than the current ones, and the availability and applicability of new construction technologies would be improved by simplifying the construction cost calculation process more.

• Korean Journal of Clinical Pharmacy
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• v.26 no.1
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• pp.59-69
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• 2016

Background: The subcutaneous formulation of biologic disease-modifying antirheumatic drugs (DMARDs) was preferred due to favored self-administration and would be an economical treatment option for patients with rheumatoid arthritis. This study was to compare the economic impact of biologic DMARDs administered by subcutaneous injection in patients with rheumatoid arthritis who had inadequate response to conventional DMARDs. Methods: The cost-minimization analysis was conducted to estimate the lifetime health care costs of treatment sequences with subcutaneous biologic DMARDs as first-line therapy from a health care system perspective. The Markov model was developed to represent the transitions through treatment sequences based on American College of Rheumatology response rate and discontinuation rate. The health care costs comprised the cost of medications, administration, dispensing, outpatient visits, test/diagnostic examination, palliative therapy and treatment of serious infection. All costs were expressed in 2016 Korean Won (KRW) and discounted at 5%. Results: The mean lifetime health care cost per patient was lowest in the etanercept sequence, which was estimated at KRW 63,441,679. The incremental costs of the treatment sequence started with adalimumab, golimumab, abatacept, and tocilizumab were KRW 7,985,730, KRW 4,064,669, KRW 2,869,947, and KRW 4,282,833, respectively, relative to etanercept sequence. These differences in costs mainly were attributable to medication costs. One-way and probabilistic sensitivity analyses confirmed that etanercept represented the option with the lowest cost compared with comparators. Conclusion: This study found that etanercept is likely a cost-saving treatment option among subcutaneous biologic DMARDs in patients with rheumatoid arthritis.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.2
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• pp.129-136
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• 2017

Among the information technology and automation that have rapidly developed in the manufacturing industries recently, tens of thousands of quality variables are estimated and categorized in database every day. The former existing statistical methods, or variable selection and interpretation by experts, place limits on proper judgment. Accordingly, various data mining methods, including decision tree analysis, have been developed in recent years. Cart and C5.0 are representative algorithms for decision tree analysis, but these algorithms have limits in defining the tolerance of continuous explanatory variables. Also, target variables are restricted by the information that indicates only the quality of the products like the rate of defective products. Therefore it is essential to develop an algorithm that improves upon Cart and C5.0 and allows access to new quality information such as loss cost. In this study, a new algorithm was developed not only to find the major variables which minimize the target variable, loss cost, but also to overcome the limits of Cart and C5.0. The new algorithm is one that defines tolerance of variables systematically by adopting 3 categories of the continuous explanatory variables. The characteristics of larger-the-better was presumed in the environment of programming R to compare the performance among the new algorithm and existing ones, and 10 simulations were performed with 1,000 data sets for each variable. The performance of the new algorithm was verified through a mean test of loss cost. As a result of the verification show, the new algorithm found that the tolerance of continuous explanatory variables lowered loss cost more than existing ones in the larger is better characteristics. In a conclusion, the new algorithm could be used to find the tolerance of continuous explanatory variables to minimize the loss in the process taking into account the loss cost of the products.