• 한국해양공학회지
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• 제34권6호
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• pp.481-488
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• 2020

Composite materialsuch as glass-fiber reinforced plastic and carbon-fiber reinforced plastic (CFRP) shows anisotropic property and have been widely used for structural members and outfitings of ships. The structural safety of composite structures has been generally evaluated via finite element analysis. This paper presents a technique for updating the finite element model of anisotropic beams or plates via natural frequencies. The finite element model updates involved a compensation process of anisotropic material properties, such as the elastic and shear moduli of orthotropic structural members. The technique adopted was based on a discrete genetic algorithm, which is an optimization technique. The cost function was adopted to assess the optimization problem, which consisted of the calculated and referenced low-order natural frequencies for the target structure. The optimization process was implemented with MATLAB, which includes the finite element updates and the corresponding natural frequency calculations with MSC/NASTRAN. Material properties of a virtual cantilevered orthotropic beam were estimated to verify the presented method and the results obtained were compared with the reference values. Furthermore, the technique was applied to a cantilevered CFRP beam to successfully estimate the unknown material properties.

• Smart Structures and Systems
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• 제19권2호
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• pp.151-161
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• 2017

A new method is developed to estimate road profile in order to estimate IRI based on the ASTM standard. This method utilizes an accelerometer and a Dynamic Tire Pressure Sensor (DTPS) to estimate road roughness. The accelerometer measures the vertical axle acceleration. The DTPS, which is mounted on the tire's valve stem, measures dynamic pressure inside the tire while driving. Calibrated transfer functions are used to estimate road profile using the signals from the two sensors. A field test was conducted on roads with different quality conditions in the city of Brockton, MA. The IRI values estimated with this new method match the actual road conditions measured with Pavement Condition Index (PCI) based on the ASTM standard, images taken from an onboard camera and passengers' perceptions. IRI has negative correlation with PCI in general since they have overlapping features. Compared to the current method of IRI measurement, the advantage of this method is that a) the cost is reduced; b) more space is saved; c) more time is saved; and d) mounting the two sensors are universally compatible to most cars and vans. Therefore, this method has the potential to provide continuous and global monitoring the health of roadways.

• Journal of Power Electronics
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• 제12권1호
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• pp.75-82
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• 2012

Elimination of rotor position sensors mechanically coupled with the rotor shaft is attractive to variable speed drives primarily due to increased system reliability and cost reduction. In this regard, search for a simple and robust position sensorless control has been intensified in past few years specifically for low-cost, high-volume applications such as home appliances. This paper describes a new parameter insensitive position sensorless control for switched reluctance motor (SRM) drives satisfying such a need in this market segment. Two consecutive switch-on times of the controllable switch in hysteresis current control are compared to estimate the rotor position and speed. The proposed sensorless control algorithm is very simple to implement since it does not depend on extensive computation or any additional hardware. In addition, the proposed method is robust in that its dynamic performance is least affected by system parameter variations. The proposed approach is demonstrated on a single-controllable-switch-converter-driven SRM with two-phases that lends itself to a system with low cost and compact packaging which comes close to the intended applications. Analysis and simulation results followed by experimental verification are presented to demonstrate the feasibility of the proposed sensorless control method.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.228.2-228.2
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• 2010

In this work, the hydrogen production costs of the nuclear energy sources are estimated in the necessary input data on a Korean specific basis. G4-ECONS was appropriately modified to calculate the cost for hydrogen production of HTE process with Very High Temperature nuclear Reactor (VHTR) as a thermal energy source rather than the LUEC (Levelized Unit Electricity Cost). The general ground rules and assumptions follow G4-ECONS. Through a preliminary study of cost estimates, we wished to evaluate the economic potential for hydrogen produced from nuclear energy, and, in addition, to promptly estimate the hydrogen production costs for an updated input data for capital costs. The estimated costs presented in this paper show that hydrogen production by the VHTR could be competitive with current techniques of hydrogen production from fossil fuels if $CO_2$ capture and sequestration is required. Nuclear production of hydrogen would allow large-scale production of hydrogen at economic prices while avoiding the release of $CO_2$. Nuclear production of hydrogen could thus become the enabling technology for the hydrogen economy. The major factors that would affect the cost of hydrogen were also discussed.

• 간호행정학회지
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• 제9권2호
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• pp.205-216
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• 2003

Purpose : This study wad aimed to estimate nursing cost for hemodialysis of secondary hospitals using Resource Based Relative Value Scale(RVRBS). Method : The first, calculated nursing workload for the hemodialysis of secondary hospitals. Second, measured each spent time according to 14 nursing behaviors. Third, computed Resource Based Relative Value(RBRV) scores and nursing expenses of hemodialysis nurse. Finally, estimated nursing cost for hemodialysis of secondary hospitals, Result & Conclusion : The mean RBRV scores for each nursing behaviors were from 218.9 to 383.9 point(mean=312.7). The high RBRV socres were 383.9(Complication during hemodialysis), 353.7(Access patient vascular), 345.7 (Patient Teaching). Nursing cost for hemodialysis was estimated 23,234(won).

• 한국IT서비스학회지
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• 제4권1호
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• pp.129-139
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• 2005

This paper proposes a framework of Operational Risk-based Business Continuity System(ORBCS), and develops protection system for operational risk through operational risk assessment and loss distribution approach based on risk management guideline announced in the basel II. In order to find out financial operational risk, business processes of domestic bank are assorted by seven event factors and eight business activities so that we can construct the system. After we find out KRI(Key Risk Indicator) index, tasks and risks, we calculated risk possibility and expected cost by analyzing quantitative data, questionnaire and qualitative approach for AHP model from the past events. Furthermore, we can assume unexpected cost loss by using loss distribution approach presented in the basel II. Each bank can also assume expected loss distributions of operational risk by seven event factors and eight business activities. In this research, we choose loss distribution approach so that we can calculate operational risk. In order to explain number of case happened, we choose poisson distribution, log-normal distribution for loss cost, and estimate model for Monte-Carlo simulation. Through this process which is measured by operational risk. of ABC bank, we find out that loss distribution approach explains closer unexpected cost directly compared than internal measurement approach, and makes less unexpected cost loss.

• 한국임상약학회지
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• 제20권3호
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• pp.268-277
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• 2010

This study was conducted to analyze the cost-utility of ramosetron monotherapy, trimebutine monotherapy and trimebutine+loperamide combination therapy in male diarrhea-predominant patients with irritable bowel syndrome (IBS) in Korean healthcare setting. We constructed a decision-analytical model to estimate both total costs for each state of health and outcomes such as IBS-symptoms improvement for 3 and 6 months time horizon. Base analysis found that for ramosetron treatment with the price of KW910 for 5 ${\mu}g$ tablet, incremental cost effectiveness ratios (ICERs, cost per quality-adjusted life day) were KW85,000 and KW62,000 for 3 months and 6 months, respectively, compared with trimebutine. But ramosetron was a dominant strategy when compared with trimebutine+loperamide for both 3 months and 6 months. Sensitivity analyses showed robust results for drug acquisition costs till ramosetron price of KW950/tablet. In conclusion, ramosetron was a cost-effective regimen compared with trimebutine or trimebutine+loperamide from the societal perspective.

• 한국건축시공학회지
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• 제12권4호
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• pp.401-414
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• 2012

The adoption of Green Frame is expected to provide economic benefits, since construction costs are reduced by the in-situ production of precast concrete column and beam. The cost reduction can ultimately be realized by saving transportation costs and the overhead and profit of PC plants. The cost structure of Green Frame, which is built up using composite precast concrete members, is similar to that of a bearing-wall structure, but the difference in construction process has resulted in some cost differences for a few items. In particular, production and installation is the principal work involved in Green Frame made by precast concrete members, while form and concrete work is the principal work for a bearing-wall structure. As such, the rental time and fee for a tower crane should be compared through time analysis. To verify reliability, this study focused on developed residential projects to estimate the construction costs. Through this analysis, it was found that the costs of Green Frame were 1.57% lower than the costs of bearing-wall structure. The results of this study will help in the development of a management plan for the structural work of Green Frame.

• 대한간호학회지
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• 제22권2호
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• pp.185-206
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• 1992

In this study nursing activities were examined to determine the nursing cost. A professional nursing group developed a tool for the investigation. 128 nursing activities were identified by the tool in 16 nursing care areas as referenced in the literature. Each activity was examined for four essential factors to define nursing cost ; time consumed for the care, level of professional skill, degree of independency and performer of the care. The activity was rated by a five point Likert scale. This investigation was conducted with the nursing staffing working in the 21 university hospitals in Korea and having more than four years experience especially in medical or surgical wards. The participating nursing staff were screened on the basic of the recommendation of the nursing director. The data were gathered from June 12th to August 12th, 1989. All the data were analyzed for mean, standard deviation, percent, and correlation coefficients between items. The results are summarized as follows : 1. Direct nursing care was classified into 16 large areas and 128 small activities. 2. No significant correlation was found between the study items of each activity. 3. Among 128 nursing activities, Those performed less than 50% of the time by a nurse were excluded from the nursing cost. Also excluded activities which were given less than 9 marks in all three items, time consumed, level of professional skill, and degree of independency. As a result, 83 activities in 14 nursing care areas were selected for the proposal to estimate nursing cost.

• Journal of Construction Engineering and Project Management
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• 제5권1호
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• pp.26-31
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• 2015

Success of the construction companies is based on the successful completion of projects within the agreed cost and time limits. Artificial neural networks (ANN) have recently attracted much attention because of their ability to solve the qualitative and quantitative problems faced in the construction industry. For the estimation of cost and duration different ANN models were developed. The database consists of data collected from completed projects. The same data is normalised and used as inputs and targets for developing ANN models. The models are trained, tested and validated using MATLAB R2013a Software. The results obtained are the ANN predicted outputs which are compared with the actual data, from which deviation is calculated. For this purpose, two successfully completed highway road projects are considered. The Nftool (Neural network fitting tool) and Nntool (Neural network/ Data Manager) approaches are used in this study. Using Nftool with trainlm as training function and Nntool with trainbr as the training function, both the Projects A and B have been carried out. Statistical analysis is carried out for the developed models. The application of neural networks when forming a preliminary estimate, would reduce the time and cost of data processing. It helps the contractor to take the decision much easier.