• New & Renewable Energy
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• v.18 no.3
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• pp.43-59
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• 2022

The green premium is the most important feature of Korea's RE100 system. Green premium has three characteristics. The first, the cost of implementation is lower than that of other means of implementation. The second, it is linked with the RPS system to keep the means of implementing the green premium low. Third, the funds raised by the green premium are used to supply renewable energy to compensate for the additionality that the green premium does not have. When the entire industrial sector's electricity consumption is converted to renewable energy, the implementation cost of the green premium is estimated to be 3,377.4 billion won, and the REC purchase is estimated to incur the implementation cost of 6,576.4 billion won, which is 3.5 trillion more than the green premium. It was analyzed that an additional implementation cost of KRW 100 million would occur. In addition, in the case of solar PPA, it was analyzed that additional implementation costs of KRW 13,375.7 billion to KRW 16,162.3 billion were incurred. It was estimated that the renewable energy that could be supplied to the green premium would at least be sufficient for companies exporting to the US and EU. In addition, it was analyzed that when the fund created as a green premium is used for renewable energy supply, about 30.7% of the renewable energy supply through PPA can be supplied. However, as ESG is emphasized, green premium can be criticized by green washing because there is no additionality. There is also a limit to responding to the EU's CBAM. Therefore, companies can use the green premium depending on the situation, but it is more advantageous to use PPA, etc. The government needs to sufficiently maintain the supply of renewable energy using the fund to maintain the green premium.

• Korean Journal of Biological Psychiatry
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• v.7 no.2
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• pp.198-205
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• 2000

Objectives : Risperidone and clozapine belong to a new generation of antipsychotics that are reportedly more effective and better tolerated than conventional neuroleptics. However, each of these agents costs far more per unit than conventional neuroleptics. The purpose of our retrospective study was to ascertain the total cost and effectiveness of treatment before and after administration of risperidone and clozapine in "revolving door" schizophrenia patients. Method : Data collected on revolving door schizophrenics for 2 years before clozapine and risperidone treatment and for at least 2 years after clozapine and risperidone treatment. Direct cost of inpatient and outpatient treatment was measured. Effectiveness was scaled as "years of mild disability gained". Result : Both risperidone and cloazpine result in higher costs and additional benefits to patients, for example, increased mild disability, reduced number of relapse, and reduced hospital length-of-stay. An ICER of risperidone was less than Rc and ICER of clozapine was greater than Rc. According to decision-analytic this model, risperidone had favorable cost-effectiveness ratios relative to clozapine. Conclusion : We have assumed that risperidone is more cost-effective than clozapine.

• ETRI Journal
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• v.22 no.1
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• pp.30-37
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• 2000

Existing tree construction mechanisms are classified into source-based trees and center-based trees. The source-based trees produce a source-rooted tree with a low delay. However, for the applications with multiple senders, the management overheads for routing tables and resource reservations are too high. The center-based trees are easy to implement and manage, but a priori configuration of candidate center nodes is required, and the optimization mature such as tree cost and delay is not considered. In this paper, we propose a new multicast tree building algorithm. The proposal algorithm basically builds a non-center based shared tree. In particular, any center node is not pre-configured. In the purposed algorithm, a multicast node among current tree nodes is suitably assigned to each incoming user: Such a node is selected in a fashion that tree cost and the maximum end-to-end delay on the tree are jointly minimized. The existing and proposed algorithms are compared by experiments. In the simulation results, it is shown that the proposed algorithm approximately provides the cost saving of 30% and the delay saving of 10%, compared to the existing approaches. In conclusion, we see that the cost and delay aspects for multicast trees can be improved at the cost of additional computations.

• Korean Journal of Construction Engineering and Management
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• v.6 no.6 s.28
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• pp.98-106
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• 2005

The construction cost index and the forecasting model of apartment house can be efficient for evaluating the validness of the fluctuating price, and for making guidelines for construction firms when calculating their profit. In this study the previous construction cost index of apartment house was improved, and the forecasting model based on X-12 ARIMA was developed. According to the result, during the last five years the construction cost, excluding labor expense, has risen approximately to 22.7%. And during next three years, additional 16.8% rise of construction cost is expected. Those quantitative results can be utilized for evaluating the apartment house's selling price in an indirection, and be helpful to understand the variation pattern of the price.

• International Journal of Highway Engineering
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• v.17 no.3
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• pp.1-12
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• 2015

PURPOSES : This paper presents a description of the current issues facing road managers regarding the surface-type conversion of low-volume roads for cost savings. METHODS: The paper reviews previous works conducted toward this end, acknowledges gaps in the current research, and lays out what information is needed for further studies. RESULTS : If the cost to maintain an unsurfaced road is less than the cost of maintaining a surfaced road, then there is potential for cost savings for the management agency. However, the problem is bigger than simply maintaining the roads that already exist. If unsurfaced roads prove to be more economical than surfaced roads, then the cost to convert from a surfaced to an unsurfaced roadway, and vice versa, when necessary, must also be examined. CONCLUSIONS : No other studies have addressed the un-surfacing of a road for cost savings, and it is therefore unknown whether substantial savings can be realistically obtained by converting from a surfaced to an unsurfaced road. To determine whether a conversion policy would be a viable option, additional data and research are needed.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.2051-2057
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• 2008

This paper is a feasibility study on the calculation of operating cost in regards to the overall operation following the completion of a number of LRT lines currently in progress. Owing to the absence of operating experience in driveless LRT system at home, the difficulties lie in the assumption of the optimal operating budget applying domestic real situation. Nevertheless, with 34 years of accumulated operating experience in heavy rail transit system, Seoul Metro, the nation's biggest urban rail transit operator, performs O&M consultancy services for several on-going projects along with every effort to acquire know-how where the appropriateness of the cost estimation as a required deliverable is reviewed and a more efficient way is provided. The main focus of this study is to seek a method to calculate the optimal amount of operating expenses as well as a cost-effective alternative for possible weaknesses from the standpoint of the operator. The body of this paper discusses the five issues such as personnel cost, overhead, maintenance cost, additional purchase price, alternative investment fee from a more macroscopic point of view, and the conclusion deals with the adequacy of the reason for selection of institutions with various operating know-how.

• ETRI Journal
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• v.43 no.3
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• pp.459-470
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• 2021

This paper presents a low-cost prototype for monitoring online the maximum power produced by a domestic photovoltaic (PV) system using Internet of Things (IoT) technology. The most common tracking algorithms (P&O, InCond, HC, VSS InCond, and FL) were first simulated using MATLAB/Simulink and then implemented in a low-cost microcontroller (Arduino). The current, voltage, load current, load voltage, power at the maximum power point, duty cycle, module temperature, and in-plane solar irradiance are monitored. Using IoT technology, users can check in real time the change in power produced by their installation anywhere and anytime without additional effort or cost. The designed prototype is suitable for domestic PV applications, particularly at remote sites. It can also help users check online whether any abnormality has happened in their system based simply on the variation in the produced maximum power. Experimental results show that the system performs well. Moreover, the prototype is easy to implement, low in cost, saves time, and minimizes human effort. The developed monitoring system could be extended by integrating fault detection and diagnosis algorithms.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.1
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• pp.87-111
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• 2021

Nuclear power plants (NPPs) produce radioactive waste and decommissioning this waste entails additional cost; determining these costs for various types and specifications of radioactive waste can be challenging. The purpose of this study is to identify major determinants of the decommissioning cost and their impact on NPPs. To this end, data from defunct NPPs were gathered and 2SLS (Two Stage Least Squares) regression models were developed to investigate the major contributors depending on the reactor types, viz. PWR (Pressurized Water Reactors) and BWR (Boiling Water Reactors). Additionally, cost estimations and the Monte Carlo simulation were performed as part of performance validation. Our study established that the decommissioning costs are primarily influenced by the level of radioactivity in the decommissioned waste, which can be realized from operational factors like operation period, overall efficiency, and plant capacity, as well as from duration of decommissioning and labour cost. While our study provides an improved statistical approach to recognize these factors, we acknowledge that our models have limitations in forecasting accurately which we envisage to bolster in future studies by identifying more substantive factors.

• Korean Chemical Engineering Research
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• v.59 no.3
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• pp.467-479
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• 2021

Abstract: A kinetic model was developed for the dehydration of ethanol to ethylene based on two parallel reaction pathways. Kinetic parameters were estimated by fitting experimental data of powder catalysts in a lab-scale test, and the effectiveness factor was determined using data from pellet-type catalysts in bench-scale experiments. The developed model was used to design a multitubular fixed-bed reactor (MTR) and an adiabatic reactor (AR) at a 10 ton per day scale. The two different reactor types resulted in different process configurations: the MTR consumed the ethanol completely and did not produce the reaction intermediate, diethyl ether (DEE), resulting in simple separation trains at the expense of high equipment cost for the reactor, whereas the AR required azeotropic distillation and cryogenic distillation to recycle the unreacted ethanol and to separate the undesired DEE, respectively. Quantitative analysis based on the equipment and annual energy costs showed that, despite high equipment cost of the reactor, the MTR process had the advantages of high productivity and simple separation trains, whereas the use of additional separation trains in the AR process increased both the total equipment cost and the annual energy cost per unit production rate.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.68 no.4
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• pp.513-522
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• 2019

We calculate the benefit of distributed combined heat power generators from avoiding a transmission expansion cost by building distributed generators near electricity demand centers. We determine a transmission expansion plan by solving a mixed integer linear problem, where we modify capacities of existing transmission lines and build new transmission lines. We calculate the benefit by comparing the sum of generation and transmission expansion costs with or without distributed generators through two simulation frames. In the first frame, for the current demand, we substitute existing distributed generators for non-distributed generators and measure an additional cost to balance the generation and demand. In the second frame, for increased future demand, we compare the cost to invest only in distributed generators to the cost to invest only in non-distributed generators. As a result, we show that the distributed generators have at least 5.8 won/kWh of the benefit from avoiding the transmission expansion cost.