• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.217-227
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• 2008

The purpose of this research is the estimation of a transfer ratio according to transfer time reflecting passenger attributes such as sex, age, income, job, the car ownership, and other variables with the assumption that a transfer ratio would be different depending on each passenger attribute. This research tested transfer time through a question-survey, estimated transfer time according to the passenger attributes using a data sample, and presented some applicable models about marginal transfer time for the case of the determination of transfer ratios according to transfer time. In this research the sample which had been surveyed for passengers walking to access a transfer station was used to test and estimate and the question was present walking time to the transfer time and the marginal transfer walking time.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.15 no.26
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• pp.151-157
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• 1992

This paper presents a method for analyzing the transfer lines with finite storage buffers. Each machine spends a random amount of time processing each material. This transfer line can be modeled by the tandem queueing system with finite buffers. The great dimensionality of the state space renders the analysis of such system a formidable task. We propose an efficient algorithm to obtain the marginal state probabilities based on the exact algorithm for the two-machine system. Other performance measures, such as the utilization, the blocking probability, the average sojourn time, and the average queue length, can be easily calculated.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.1
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• pp.147-157
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• 2013

This study developed the transit transfer mode choice model aimed Daegu transit users using multinomial logit model. Dependent variables of estimating multinomial logit model were transit transfer modes such as bus to bus, bus to subway, subway to subway, bus to others, and subway to others, and explanatory variables which affect transit transfer mode choice were sex, age, occupation, handicap, transfer area, purpose of travel and travel time. Also probability regarding explanatory variables was estimated using multinomial logit model and limit marginal analysis was carried out according to explanatory variables(cost, time). In the results, indicating goodness of fit is very reasonable as ${\rho}^2$=0.354. According to the result of marginal analysis for the selection of probability, when travel time is increased, users of bus to bus and bus to subway prefer to use subway to subway. Furthermore users of bus to bus and bus to subway prefer to use bus to others and subway to others when travel cost is increased in the result of marginal analysis for the selection of probability.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.629-634
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• 2000

This System is developed for the estimation of the Camera Lens Resolution. Signal data proportional to light intensity is obtained and sampled from the 2D CCD. Based on the measured signal. the MTF charateristcs of a camera lens are measured. We could measure the sagittal and tangential MTF in the on and off-axis at the same time. The automatic measurig methods for optimal image plane, magnification, and best marginal direction of test lens are presented.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1480-1491
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• 2015

In new deregulated electricity market, short-term price forecasting is key information for all market players. A better forecast of market-clearing price (MCP) helps market participants to strategically set up their bidding strategies for energy markets in the short-term. This paper presents a new prediction strategy to improve the need for more accurate short-term price forecasting tool at spot market using an artificial neural networks (ANNs). To build the forecasting ANN model, a three-layered feedforward neural network trained by the improved Levenberg-marquardt (LM) algorithm is used to forecast the locational marginal prices (LMPs). To accurately predict LMPs, actual power generation and load are considered as the input sets, and then the difference is used to predict price differences in the spot market. The proposed ANN model generalizes the relationship between the LMP in each area and the unconstrained MCP during the same period of time. The LMP calculation is iterated so that the capacity between the areas is maximized and the mechanism itself helps to relieve grid congestion. The addition of flow between the areas gives the LMPs a new equilibrium point, which is balanced when taking the transfer capacity into account, LMP forecasting is then possible. The proposed forecasting strategy is tested on the spot market of the Nord Pool. The validity, the efficiency, and effectiveness of the proposed approach are shown by comparing with time-series models

• Journal of Labour Economics
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• v.44 no.1
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• pp.135-167
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• 2021

This paper studies how households who received Covid-19 transfers in cash used their one-time transfers. The transfers were paid in cash for welfare recipient households, which accounted for 12.9% of all households. Using a survey data, it is found that the cash transfers are mostly used for consumption expenditure, and 21.7 percent of the cash transfer used are spent on additional consumption not originally planned. The consumption response to cash transfers is greater in households that experienced job or income loss because of Covid-19.

• Journal of Korean Society of Transportation
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• v.25 no.2 s.95
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• pp.121-132
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• 2007

This paper addressed the issue of a generalized cost model for transit assignment. The model composed of walk time, waiting time (including transfer waiting time), line-haul time, transfer walk time, and fare. The weights of each component were supposed to be calculated using the stated preference (SP) data, which were collected prudently in order to reflect reality. The marginal rate of substitution and wage rate were applied to calculate the weights. The results showed that the weight of walking time per in-vehicle travel time (IVTT) was 1.507, the weight of waiting time (per IVTT) was 1.749, that of transfer time (per IVTT) was 1.474, and that of fare (per IVTT) was 1.476 for trips between inner-city areas in Seoul. Weights for each component were identified as 1.871, 1.967, 1.015, and 0.857, respectively, for trips between Seoul and Gyeonggi. Statistical significance existed between two cases and each variable was also statistically significant. Transit assignment using the relative weights estimated in this study was implemented to analyze the travel index in a macroscopic and quantitative basis. The results showed that average total travel times were 30.23 minutes and 63.29 minutes and average generalized costs were 2,510 won and 3,880 won for trips between inner-city areas in Seoul and between Seoul and Gyeonggi, respectively.

• Korean Journal of Agricultural Science
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• v.40 no.3
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• pp.237-241
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• 2013

This study started to export an orchard tractor to Europe under the situations that R&D activities for orchard tractor were marginal and even it was not produced. The R&D for orchard tractor has been progressed and the most of it is accomplishing the goal. In this study, the durability of clutch friction part was tested for F/R clutch and moment of inertia of PTO clutch, and it was compared with the design criteria of transmission of tractor. According to the results of inertia test of F/R clutch, hydraulic pressures of clutch satisfied $1,961.33{\pm}196.13kPa$ of design criteria, and the variations of torque for forward and reverse operation were relatively constant. Therefore, it was found that the durability of clutch friction part was stable and reliable. Test results showed that the main hydraulic pressures were maintained $1,961.33{\pm}196.13kPa$ during the tests of moment of inertia of PTO clutch, and when it was operated, the hydraulic pressures were reached $1,961.33{\pm}196.13kPa$. Therefore, it was found that the hydraulic pressures of PTO satisfied the design criteria. By the results that the time of the hydraulic pressures of PTO reaching main hydraulic pressure, and that of torque values restoring to the original was same as the time of the first gear of PTO reaching the maximum rotational speed, it was found that PTO could transfer power to attachments as it was designed.

• Journal of the Korea Concrete Institute
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• v.17 no.6 s.90
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• pp.893-902
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• 2005

Reasonable prediction of residual capacity of fire-damaged reinforced columns is important for both the safety measurement and the rehabilitation of the reinforced concrete structures suffered from exposure to extensive fire. In order to predict the residual behavior of fire-damaged reinforced concrete columns, its predictive model must be able to take into account the amount of heat transferred into the column, the level of deterioration of constituent materials and various column geometries. The numerical model presented in this research includes all these factors. The model has been shown to reasonably predict the residual behavior of fire-damaged columns. Parametric studies were performed using this model for the effects of cover thickness, exposure time to fire and column geometries on the residual behavior of reinforced concrete columns. It was found that serious damage on the residual capacity of column resulted from a longer exposure time to fire but only marginal differences from other factors.

• Smart Media Journal
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• v.13 no.5
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• pp.33-44
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• 2024

Chungbuk has various regional characteristics in terms of population composition by region, industrial facilities, and distribution of emergency medical institutions. However, there are no studies yet that have analyzed regional characteristic factors related to the occurrence characteristics of cardiac arrest patients. Therefore, this study provided basic data to establish a response system for OHCA patients suitable for the characteristics of the Chungcheongbuk-do region by analyzing the characteristics of OHCA patients and the transfer status of 119 paramedics in Chungcheongbuk-do. This study is a retrospective study that analyzed 1,188 cardiac arrest patients transferred by ambulance based on raw data from the survey on acute cardiac arrest in Chungbuk (2020). There are a total of 11 emergency medical institutions in Chungbuk-do, which are concentrated in city-level areas, so the transfer time of patients to hospitals in county-level areas was delayed. In the county-level area, the frequency of dispatch of special paramedics was relatively small, and the frequency of administration of cardiac arrest drugs to help resuscitate cardiac arrest patients was also low. In conclusion, efforts should be made to improve accessibility of emergency medical services (deployment of emergency vehicles in marginal areas, proper placement of emergency medical institutions, etc.), to promote prevention of traumatic cardiac arrest patients, and to expand the scope of work to strengthen the first aid expertise of paramedics.