• Journal of Climate Change Research
• /
• v.7 no.3
• /
• pp.217-229
• /
• 2016

Increased evidences reveal that the global climate change adversely affect on the environment. Smart grid system is one of the ways to reduce greenhouse gas emissions in the electricity generation sector. Since 2013, Korea Electric Power Corporation (KEPCO) has installed smart grid station in KEPCO office buildings. The goal of this paper is two folds. One is to quantify the reduction in greenhouse gas emissions through smart grid stations installed in KEPCO office buildings as a part of pilot project. Among components of smart grid stations, this research focused on the photovoltaic power system (PV) and energy storage system (ESS). The other is to estimate the reduction in greenhouse gas emissions when PV is applied on individual houses. Results show that greenhouse gas emissions reduce 5.8~11.3% of the emissions generated through the electricity usage after PV is applied in KEPCO office buildings. The greenhouse gas emissions reduction from ESS is not apparent. When PV of 200~500 W is installed in individual houses, annual greenhouse gas emission reduction in 2016 is expected to be approximately $2.2{\sim}5.4million\;tCO_2-eq$, equivalent to 6~15% of greenhouse gas emissions through the electricity usage in the house hold sector. The saving of annual electricity cost in the individual house through PV of 200 W and 500 W is expected to be 47~179 thous and KRW and 123~451 thousand KRW, respectively. Results analyzed in this study show the environmental effect of the smart grid station. In addition, the results can be further used as guidance in implementing similar projects.

• Environmental and Resource Economics Review
• /
• v.29 no.4
• /
• pp.443-468
• /
• 2020

Broad effects of fuel-transition in all type of ground transportation have occurred with the help of the advances in electric vehicle (EV) technologies and the increases in EV supply. This research estimates the economic benefit of air environmental improvements, which results from the fuel-transition of high-mileage business cars(taxies) in metropolis. If we consider power production sector for EV operation, some air pollutants will be produced. In this respect, this research takes both the mixture of power sources in power production level and the driving pattern of business cars into account when investigating the economic benefit in air environment resulted from the fuel-transition of business cars(taxies). According to our results, the business cars' fuel transition from LPG to electricity brings about 21.5￦/km (8.6million won/year) of economic benefit in air environment. These results emphasize the necessity and appropriateness of public polices for expanding power production with renewable energies and facilitating EV distribution.

• ETRI Journal
• /
• v.30 no.2
• /
• pp.341-343
• /
• 2008

This letter presents an angular minimum spanning tree (AMST) algorithm for topology control in multi-hop wireless ad hoc networks. The AMST algorithm builds up an MST for every angular sector of a given degree around each node to determine optimal transmission power for connecting to its neighbors. We demonstrate that AMST preserves both local and network-wide connectivity. It also improves robustness to link failure and mitigates transmission power waste.

• Proceedings of the KIPE Conference
• /
• 2011.07a
• /
• pp.283-284
• /
• 2011

Generally, it is important to use the regenerative energy efficiently for decrease of inverter's consuming energy. From various industry sector (railroad, steel, crane etc), re-uses the regenerative energy which uses the regenerative converter unit, and gets a many profit from whole consuming energy. In this paper, we introduce development of the regenerative converter unit that supply the regenerative energy to power source and main drive inverter, and introduce the instance which is applied in the elevator.

• Journal of the Korean Society of Industry Convergence
• /
• v.22 no.4
• /
• pp.395-403
• /
• 2019

The excessive need of power is creating an unbalance situation in power sector, where solar energy is one of the best solutions among other energy sources to mitigate this demand. It is globally accepted because of its flexibility and long life compared to others. A lot research is going on to enhance the energy efficiency by introducing photovoltaic (PV) power generation technology, but still irradiation of PV power is the major problem. In this manuscript, we have designed PV module using single diode methodology and also the solar conversion efficiency was boosted with maximum power point tracking (MPPT) by using perturb and observe (P&O) algorithm. The simulation was done for $1000W/m^2$ and $800W/m^2$ at solar irradiance in cell temperature of 25C and 40C degree levels in PSIM tool.

• Journal of the Korean Society of Visualization
• /
• v.2 no.1
• /
• pp.3-7
• /
• 2004

Two novel industrial combustion technologies are introduced. High temperature air regenerative combustion for industrial heating system and oxyfuel combustion for power plant are considered as a energy saving and $CO_{2}$ emission reducing combustion technology. Research works are necessary to understand fundamental phenomena and to develope application technologies to industrial sector.

• Journal of Agricultural Extension & Community Development
• /
• v.11 no.2
• /
• pp.251-265
• /
• 2004

The agricultural sector's economic structure in Korea is regarded to encounter major barriers on the way toward revitalizing its economic prosperity. Among many, the energy-related problem is one of prime nuclei embedded in the country's agricultural sector. The ought-to-come structural changes in the country's agricultural energy system hinge upon the central government's policy direction as well as efforts of local governments and local farming community members. The indirect aids via 'cross subsidy' of electricity tariff rate and 'tax-exempt price' of oil fuels are two notable causes of the unsustainable energy consumption pattern in the country's agricultural sector. As measures, demand-side management(DSM) and energy-efficiency promotions are regarded to be the most attractive methods for energy conservation and economic productivity as well. Development of renewable energy sources are also receiving a great deal of attention for the long-term alternatives to the country's existing oil-based agricultural production mode. This study examines the contributive potential of DSM approaches and renewables-based technologies. With the critical evaluation on the concurrent adversities of the country's agricultural energy system, various sources of renewable energy-solar power, wind power, biomass, etc.-are examined for the purpose of technological and economical viability. As sufficient potentials of renewable energy sources are being estimated, both the system production cost and the installation cost for the county's rural areas are expected to lower in the long term. DSM options are also evaluated to be fruitful even in the short term. Both the public and civil arenas must galvanise each side's effort in order to promote these policy options and community potentials.

• Explosives and Blasting
• /
• v.25 no.2
• /
• pp.11-21
• /
• 2007

The main structure of Gunsan steam power station was demolished by the toppling method using high explosives. Height of a main building is 58m and a total floor area is $292,000m^2$. It is Rahmen(rigid-frame) structure consisted of almost columns and beams and slabs exist only in one part of the building for the electricity generators equipments. To improve the efficiency of blasting work, it is separated into 4 sectors. Blasting floors were 1, 2, 3, & 4 stories from first sector to third sector, while 1, 2, 5, & 7 of fourth sector were blasted because it had not slabs. About 102.675 kg of the MegaMITE were used with 225 electric detonator and 638 non-electric detonators to check detonator connection and confidence of detonation. The blasting noise and vibration were monitored to evaluate the environment effect and the damage of the nearby structures.

• Journal of the Korean Data and Information Science Society
• /
• v.24 no.4
• /
• pp.701-712
• /
• 2013

The e-learning industry status survey statistic provides information about the actual conditions of supply and demand of the e-learning industries. NIPA (National IT Industry Promotion Agency) has published the annual report of the survey results since 2004. Due to the 9th version of the KSIC (Korean standard industrial classification) revised in 2008, a refinement of the sampling design for the survey becomes necessary, especially that for the business demand sector. This article, based on the 9th revision of the KSIC, constructs a stratification of the target population used for the e-learning industry status survey on the business demand sector. Classification of strata in the business population is based on the industrial type and employment scale of business. Under the stratified population, we design a sampling scheme by using the power allocation method that enables us to satisfy a target coefficient of variation of each industrial stratum. In order to secure an accurate survey results based on the proposed sampling design, we consider the problem of calculating the design weights, derivation of parameter estimators, and formulas of their standard errors.

• Journal of the Society of Disaster Information
• /
• v.15 no.2
• /
• pp.268-281
• /
• 2019

Purpose: The purpose of this study was to find out how the administrative paradigm of the times affected the public sector's fire. Method: For this purpose, we investigated the New Public Management (NPM). In addition, the reasons of fire accident of Boryeong thermal power plant were analyzed in the limited values of NMP. Result: In theoretical investigation, the 3 values (managerial accountability, efficiency, expertise) of NMP and evaluation criteria were drew out. In investigation on reasons of fire accident, the improvement of accountability and expertise was insufficient due to the emphasis of the efficiency based on the introduction to free market by neoliberalism in public sector. Conclusion: In conclusion, we confirmed that the values of NMP were limited to forcingly apply to the public sector. This study is expected to contribute basic research references to fire administration theory.