• Environmental and Resource Economics Review
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• v.26 no.2
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• pp.173-203
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• 2017

The existence of rebound effect from road extension in Korea has been quantitatively verified using cross-sectional, time series data on four major cities - Seoul, Busan, Daegue and Incheon - between 2000 and 2013. The linear mixed effects model was constructed from six variables: total vehicle miles traveled (VMT), road extension, public transport users, gross regional domestic product (GRDP), regional population and fuel consumption. The main results can be summarized as VMT is positively correlated to road extension while negatively with public transport users. It indicates that the road extension-centered "supply-side" transportation policy induces "additional travel" and create "generated traffic" by enhancing driving efficiencies directly, or degrading other transport modes indirectly. Hence, the ultimate goal of road congestion reduction requires public transport-centered "demand management" rather than current supply-side policies.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.10
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• pp.231-238
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• 2013

This paper describes a DC-DC converter IC for Flat Panel Displays. In case of operate LCD devices various type of DC supply voltage is needed. This device can convert DC voltage from 6~14[V] single supply to -5[V], 15[V], 23[V], and 3.3[V] DC supplies. In order to meet current and voltage specification considered different type of DC-DC converter circuits. In this work a negative charge pump DC-DC converter(-5V), a positive charge pump DC-DC converter(15V), a switching Type Boost DC-DC converter(23V) and a buck DC-DC converter(3.3V). And a oscillator, a thermal shut down circuit, level shift circuits, a bandgap reference circuits are designed. This device has been designed in a 0.35[${\mu}m$] triple-well, double poly, double metal 30[V] CMOS process. The designed circuit is simulated and this one chip product could be applicable for flat panel displays.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.460-466
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• 2017

The common petroleum can make precipitation such as a wax in a polar region due to severely cold weather condition, which can cause problems to fuel supply system. The petroleum product used in the polar region has thus been manufactured and sold suitable for the cold environment. However it is difficult to supply such petroleum products on time since these were mainly supplied abroad. In this article, the original fuel properties were first analyzed in order to find alternative fuel products for polar region. Jet fuel which is excellent cold characteristics was chosen and the fuel properties was tested by adding a constant concentration of lubricant additives to the jet fuel. As a result, the lubricant additive R621 showed the best lubricity, and adding 1000 mg/L of R621 content to the jet fuel was sufficient to enhance the lubricity. We envision that the jet fuel added 1000 mg/L of R621A can be suitable for alternative special antarctic blend diesel (SAB) in an severe polar environment.

• Information Systems Review
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• v.5 no.1
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• pp.1-18
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• 2003

Many organizations experience that the value they gained from IT (information technology) investment is lower than they expected prior to the actual implementation of a system - the value gap between expected value and realized value from IT. Research on the barriers to the expectation and realization is of high importance both in practice and in IS research. This study analyzed such barriers observed in three companies that have adopted such IT systems as Enterprise Resource Planning (ERP), Supply Chain Management (SCM), and Customer Relationship Management (CRM) systems each. From analyses of the three companies we specifically identified eight types of barriers: barriers related to industry, organization, knowledge, resource, usage, competence, product, and safety. Common barriers among the three cases were classified into six types, e.g. lack of strategic mind-set, improper organizational structure, lack of human resource, etc. We expect that the results help managers in IS investment to minimize the valuation gap and maximize realized values.

• Journal of the Korean Institute of Gas
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• v.18 no.1
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• pp.25-30
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• 2014

Mixture of hydrogen and natural gas HCNG mixing equipment production and refueling experiment were performed for supply and product. Hydrogen and CNG in 30 : 70 ratio is mixing of HCNG was performed using ratio control. HCNG refueling method was calculated after reading the pressure of tank for full refuel, amount refuel. Both full refuel and amount refuel results mixed ratio 30 : 70 in the error limits of $H_2{\pm}2%$ met the criterion. HCNG composition analysis result in refueling tank using gas chromatography is satisfying the error limits in refuel tank 30 : 70 ratio were confirmed.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2007.05a
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• pp.83-125
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• 2007

Increasing energy costs have caused profitability problems for paper suppliers. Therefore unprofitable lines are being closed down. The actions aiming for improved profits are focused either on cost savings or on increasing the capacity of the remaining machines. The runnability of a paper machine and its total efficiency have a significant effect on energy consumption. Producing one ton of waste paper consumes at least as much energy as producing the same amount of sellable end product. New automation solutions enable significant cost-effective improvements to the total efficiency of a line without large investment projects. The measures focus on minimizing changes, interruptions, interruption recovery times and grade change times. Newest actuators, online quality measurements and wet end analysators create an improvement potential, which can be optimally implemented with the latest machine direction control solutions, based on model predictive control concepts. Equally, drying management is significant to the energy consumption. The newest control strategies optimize the use of various drying actuators for different situations; either by responding to changes as efficiently as possible or by using only the cheapest energy sources in stable situations. An even steam supply, which is vital for paper machines, is achieved with control for the power plant steam network. This makes possible to avoid the delays upon starting the paper machine and assure an even steam supply for the drying section and the actuators. This document describes means which have brought significant energy and raw material savings for paper machines. Metso Automation has provided efficiency improvement packages, which are usually based on optimized control of dry weight and drying in all running conditions. The solutions are based on performance analysis, on which the estimations for improvement potential and the necessary actions are based on. Typically benefits on an annual level have been from hundreds of thousands of euros to over one million euro. For example, variations in dry weight have been decreased more than 50%. The results are presented with a few examples. Additionally, the analysis models, adjustment solutions and the changes in running methods with which the results were achieved, are presented.

• Korean Journal of Community Nutrition
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• v.17 no.3
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• pp.312-320
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• 2012

The purpose of this study was to investigate the perception of the school dietitian on superior agricultural products (SAP) and the status of using superior agricultural products in school meals. Questionnaires were distributed to 185 school dietitians after face to face interview, and a total of 181 responses were used for analysis. 82.3% of the respondents were using SAPs in school meals and there was a significant difference between elementary school (95.1%), middle school (76.8%) and high school (66.7%) dietitians (p < 0.001). 85.2% of the dietitians, who were using SAP, were purchasing SAPs through electronic bidding, and the main reason of not using SAPs was the higher price of SAPs than that of general agricultural products. The good agricultural practices (GAP) product was considered the most appropriate agricultural products for school meals by the majority of respondents (66.9%), and organic products was the next (13.3%). In addition, the most important selection criterion for a SAP perceived by school dietitians was safety (58.0%), and the main reason of using SAPs in school meals, when two choices were allowed, was 'to provide healthful food to children' (98.9%). The major barriers to using SAPs in school meals (two choices were allowed) were 'too expensive' (73.5%) and 'unstable supply' (32.6). In conclusion, it was suggested that there should be an improvement in SAP supply and management systems to increase the use of SAPs in school meals.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.3
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• pp.206-212
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• 2017

Induction motor torque is the reactive power is needed which corresponds to the exciting current to generate the magnetic flux as the product of current and flux. For use in the method of supplying the required reactive power to the induction motor power factor correction apparatus using a lot of ways to supply in place of the power supply side, when using a power factor compensation device can reduce the apparent power, the power factor can be improved. However, the distance to the emergency generator transformers or motors from the motor capacity is smaller but short and difficult to maneuver the theory and practice of the operating characteristics of the starting characteristics of the motor used a lot of large industrial plants were measured and analyzed. Therefore, this study investigated the motor starting Analysis and interpretation for the relationship with the large motor starting torque and speed during motor starting.

• Journal of Hydrogen and New Energy
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• v.31 no.5
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• pp.405-410
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• 2020

In this literature, we are introduce a basic design of multi energy hub based on natural gas governor station. Multi energy hub consists of turbo expender generator, phosphoric acid fuel cell, pressure swing adsorption, H₂ charging station, utilities and etc. We design a hybrid energy hub system that provides energy using these complex energies, and calculates the amount of electricity that can be produced and the amount of hydrogen charged through the process analysis. TEG and phosphoric acid fuel cell produce 2,290 to 2,380 kW and can supply electricity to 500 houses. In addition, By-product H₂ gas is refined to H₂ vehicle fuel. This will help maximize the balance of energy demand and supply and improve national energy efficiency by integrating unused decompression energy power generation technology and various power generation/heat source technologies.

• The Korean Journal of Food And Nutrition
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• v.20 no.4
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• pp.487-493
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• 2007

Internet websites are excellent resources for younger people to gain information related to breastfeeding. So in this study, we evaluated the breastfeeding knowledge of university students, as well as the currently available website information on breastfeeding. Among the criteria, the six most important evaluation categories for the breastfeeding information on websites were selected and identified. The study participants completed the modified Williams and Hammer's tool, in order to evaluate their breastfeeding knowledge. An additional tool took into consideration the website breastfeeding information criteria, to evaluate the Korean websites. This 34 item tool was categorized into milk supply, comfort during breastfeeding, health of the baby and mother, social support, presentation of message, and products or financial motivation. Thirty-seven websites related to breastfeeding were evaluated, and the results were then discussed by nursing students. The students in this study were not knowledgeable on breastfeeding management with regard to the expression and storage of breast milk, the prevention and care of sore nipples, or use of breastfeeding aids. The breastfeeding information found on the Korean websites received positive evaluations for milk supply, comfort during breastfeeding, and health of the baby and mother. However, the educational content on social support, the message presentation, and the product areas on websites were rare or required additional information from breastfeeding specialists. In conclusion, based on our empirical survey, we need to design websites and evaluation tools for accurate website information regarding the social and economic benefits of breastfeeding, so that Korean women are better motivated to breastfeed by the information they obtain through the Internet.