• Journal of the HCI Society of Korea
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• v.12 no.4
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• pp.65-73
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• 2017

While electricity demand is generally increasing, stably controlling supply is becoming a serious challenge because renewable energies are becoming popular and often their productions are dependent on the weather. The 'demand response' programs can be used to complement the problems of renewable energies, and therefore their role is becoming increasingly important. This study provides an analysis of a demand response pilot that was conducted in Korea. The study first focused on questionnaire surveys and in-depth interviews, and the data was used to perform a Technology Acceptance Model (TAM) analysis. The goal of the pilot was to have the residential users reduce their power consumptions when an energy reduction mission is issued during peak load hours. The experimental subjects consisted of two groups with different characteristics. Subjects in group A obtained smart meters as an optional function of IoT platform service provided by a mobile service company, and received a charge deduction as their compensation. Subjects in group B either voluntarily purchased smart meters as individuals or received them by participating in an energy self-sufficient village program that was run by a local government, and were entitled to a donation as their compensation. With the analysis, group A was found to fit the extended technology acceptance model that includes perceived playfulness in addition to perceived ease of use and perceived usefulness. On the contrary, group B failed to fit the model well, but perceived usefulness was found to be relatively more important compared to group A. The results indicate that the residential energy groups' behavior changes are dependent on each group's characteristics, and group-specific DR design should be considered to improve the effectiveness of DR.

• The Korean Journal of Emergency Medical Services
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• v.16 no.1
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• pp.65-80
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• 2012

Purpose: The objective of this study was to assess the job satisfaction and turnover intention of the emergency medical technicians (EMT) in the private ambulance service, to examine their job satisfaction and turnover intention, and to provide the solution for the management of the private ambulance service. Methods: The survey was conducted with 121 EMTs (73 paramedics, 36 basic EMTs and 12 nurses) in the private ambulance service in Korea from September 15 to October 14, 2011. In the reliability of the questionnaire, Cronbach's ${\alpha}$ was 0.790 for job satisfaction and 0.796 for turnover intention. Using SPSS 18.0, we obtained Cronbach's ${\alpha}$, frequencies, percentages, means, and standard deviations, and performed independent t-tests, ANOVA, and Pearson's correlation analysis. Results: 1) The mean score with regard to job satisfaction was 2.94 and that of their turnover intention was 4.23. In the area of job satisfaction, the mean score of the job demand area was 4.23; 3.97 for the job itself; 3.07 for the area of interaction; 2.98 for the area of autonomy: 2.67 for the organizational demand area; 2.67 for working conditions area; and 1.73 for the wage area. 2) Statistically significant difference was observed in job satisfaction according to age (F=3.819, p=.006), wages (t=-4.640, p=.000), terms of incumbency (F=3.868, p=.011), and in turnover intention it was according to sex (t=-1.995 p=.048), age (F=9.611, p=.000), education levels (F=6.974, p=.002), marital status (t=4.393, p=.000), wages (t=5.515, p=.000), license types (F=8.481, p=.001), and terms of incumbency ( F=14.115, p=.000). 3) The job satisfaction and the turnover intention had a negative correlation to each other (r=-.56, p<.000) in general, and in the sub-7 areas of job satisfaction, the correlation with turnover intention was high in order of the wage area (r=-.61, p=.000), working conditions area (r=-.52, p=.000), the area of autonomy (r=-.49, p=.000), the area of interaction (r=-.45, p=.000), the organizational demand area (r=-.40, p=.000), the job itself (r=-.24, p=.007) and the job demand area (r=-.24, p=.009). Conclusion: The government must take the charge of lowering the turnover intention among paramedics in the private ambulance service by providing the advantage in wages and fringe benefits. Ultimately, this would bring an improvement in the quality of medical emergency services to hospitals especially in the area of patient transfer and transportation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2563-2573
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• 2013

Specialty contractors are in charge of the actual construction work and managing many work force in construction sites. The effective educational program for specialty contractors' employees is essential to improve the competitiveness of construction industry. However, there is no in-depth research on training programs for their management or technical staff. Therefore, this study proposes a framework of educational program for the specialty contractors' employees in order to enhance their competence. An extended review of literature related the educational program was carried out to understand the concept, structure, and element of the education system. A questionnaire survey for specialty contractors' employees was performed to investigate the status and problems of educational programs as well as the their educational needs. Based on the survey, the demand-oriented education programs is required to meet the needs of specialty contractors' employees. The framework of demand-oriented education programs for specialty contractors' employees consists of training contents, training type and method, training hour.

• Journal of Korean Society of Transportation
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• v.34 no.6
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• pp.510-522
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• 2016

In studies involving public transport, social welfare improvement is simply explained by the increase in public transport demand. However, the increase in the demand for public transport is mostly observed by the change in the frequency of public transport service, and in-vehicle crowding in public transport has not been an object of concern. This study examines and tries to reveal the cause of the changes of the social welfare and in-vehicle crowding of the changing public transport from imposing congestion pricing. We observe that congestion pricing increases in-vehicle crowding in public transport. This predictable phenomenon is more exacerbated in case of not operating bus-only lane. It should be noted that in-vehicle crowding is more increased in suburban, but in First-best toll system it tends to get worse less than it in other congestion pricing systems. We identify that the change of in-vehicle crowding is affected by the change of proximity of the housing to workplace, the number of commuting trips, and unpredictable distortion effect of the congestion charge.

• The Journal of the Korea Contents Association
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• v.8 no.1
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• pp.377-385
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• 2008

Nowadays, the demand of functional white milk has been augmented because of the widespread well-being popularity. Especially, in case of white milk, there are brisk efforts In segmentation of the functional product, in an effort to break through the limitation of creating new demands out of fixed demands and school meal service. The companies are also looking for the solution in the development of functional white milk in that they have no other way to increase the customers' demand, but the differentiation of the product, since the companies consider that content of white milks are exactly the same that there is no need to compete. Following this, the package design availed of the development of functional milk and took important charge of conveying and emphasizing the product's functional special quality and information to customers. Consequently, in this research, we will going to look at more desirable design differentiation strategy of functional milk by examining the basics of functional milk and by analysing the functional characteristic of current products and the expression strategy of package design.

• Journal of Korean Society of Transportation
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• v.25 no.5
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• pp.183-193
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• 2007

Traditionally, a congestion charge based on first-best congestion pricing theory, namely, the theory of marginal cost pricing theory, is equal to the difference between marginal social cost and marginal private cost. It is charged on each link so as to derive a user equilibrium flow pattern to a system optimal one. Based on this theory this paper investigates on the characteristics of first-best congestion pricing of multiple user class on road with variable demand, and presents two methods for analysis of social and spatial equity. For these purposes, we study on the characteristics of first-best congestion pricing derived from system optimal in time and in monetary unit, and analyze equity from this congestion pricing with an example network.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.1
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• pp.58-73
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• 2021

Cloud Service Providers (CSPs) enable their users to access Cloud computing and storage services from anywhere in quick and flexible manners through the Internet. With the basis of 'pay-as-you-go' model, it makes the interactions between CSPs and the users play a vital role in shaping the Cloud computing market. A pool of virtualized and dynamically scalable Cloud services that delivered on demand to the users is associated with guaranteed performance and cost-provisioning. It needed a costing scheme for determining suitable charges in order to secure lease pricing of the Cloud services. However, it is hard to meet the satisfied prices for both CSPs and users due to their conflicting needs. Furthermore, there is lack of Service Level Agreements (SLAs) that allowing the users to take part into price negotiating process. The users may lose their interest to use Cloud services while reducing CSPs profit. Therefore, this paper proposes a generic costing scheme for Cloud services using General Equilibrium Theory (GET). GET helps to formulate the price function for various services' factors to match with various demands from the users. It is initially determined by identifying the market circumstances that a general equilibrium will be hold and reached. Specifically, there are two procedures of agreement made in response to (i) established equilibrium supply and demand, and (ii) service price formed and constructed in a price range. The SLAs in our costing scheme is integrated to satisfy both CSPs and users' needs while minimizing their conflicts. The price ranging strategy is deliberated to provide prices' options to the users with respect their budget limit. Meanwhile, the CSPs can adaptively charge based on users' preferences without losing their profit. The costing scheme is testable and analyzed in multi-tenant computing environments. The results from our simulation experiments demonstrate that the proposed costing scheme provides better users' satisfaction while fostering fairness pricing in the Cloud market.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.1
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• pp.175-179
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• 2021

With the recent increase in the proportion of single-person households, the demand for reasonable personal mobility has increased, and the "Personal Mobility" industry that can be used conveniently and concisely has grown rapidly. In fact, according to data from the Korea Transport Institute, the scale of the electric kickboards rental industry, one of the personal mobility industry sectors, is expected to expand to 200,000 units in 2022. Due to the characteristics of electric kickboards that are powered by electricity, stable and efficient battery supply is the most basic and important issue. According to recent reviews from users who have used the electric kickboard, there were cases where the use of the electric kickboard is attempted, but the battery is in a discharged state or the battery charge level is low and thus cannot be used. Therefore, this paper proposes a solar charging system for stable battery use of electric kickboards. When this system is applied, it is expected that it will not only be an eco-friendly charging method for electric kickboards, but also stably supply and demand batteries while driving.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.6
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• pp.1339-1348
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• 2021

There are variety of reasons for renewable energy curtailment, including lack of transmission availability and grid system stability. In the Jeju island region, there are many cases in which the supply of electricity is already increased compared to the demand for electricity due to the increase of solar and wind power generation facilities, and accordingly, the number of curtailments for wind power generation is increasing. This research aims to find the direction of efficient reception of renewable energy and stable operation of the power system using HVDC(High Voltage Direct Current) and BESS(Battery Energy Storage System) facilities that are in charge of power supply in Jeju island. And the paper suggests a practical operation plan for optimal system operation, and the direction of system operation of the land power system due to the expansion of solar and wind power generation facilities in the future.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.2
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• pp.329-333
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• 2021

V2G (Vehicle to Grid) technology for an EV (Electric Vehicle) has been assumed as so promising in a near future for its useful energy resource concept but still yet to be developed around the world for specific service purposes through various R&BD projects. Basically, V2G returns power stored in vehicle at a cheaper or unused time to the grid at more expensive or highly peaked time, and is accordingly supposed to provide such roles like peak shaving or load levelling according to customer load curve, frequency regulation or ancillary reserves, and balancing power fluctuation to grid from the weather-sensitive renewable sources like wind or solar generations. However, it has recently been debated over its prominent usage as diffusing EVs and the required charging/discharging infrastructure, partially for its addition of EV ownership costs with more frequent charging/discharging events and user inconvenience with a relative long-time participation in the previously engaged V2G program. This study suggests that a Korean DR (Demand Response) service integrated V2G system especially based upon a dynamic charge/pause/discharge scheme newly proposed to ISO/IEC 15118 rev. 2 can deal with these concerns with more profitable business model, while fully making up for the additional component (ex. battery) and service costs. It also indicates that the optimum economic, environmental, and grid impacts can be simulated for this V2G-DR service particularly designed for EV aggregators (V2G service providers) by proposing a specific V2G engagement program for the mediated DR service providers and the distributed EV owners.