• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.3
• /
• pp.454-468
• /
• 1997

This paper presents a bitwidth optimization algorithm for efficient hardware sharing in digital signal processing system. The proposed algorithm determines the fixed-point representation for each signal through bitwidth optimization to generate the hardware requiring less area. To reduce the operator area, the algorithm partitions the abstract operations in the design description into several groups, such that the operations in the same group can share an operator. The partitioning result are fed to a high-level synthesis system to generate the pipelined fixed-point datapaths. The proposed algorithm has been implemented in SODAS-DSP an automatic synthesis system for fixed-point DSP hardware. Accepting the models of DSP algorithms in schematics, the system automatically generates the fixed-point datapath and controller satisfying the design constraints in area, speed, and SNR(Signal-to-Noise Ratio). Experimental results show that the efficiency of the proposed algorithm by generates the area-efficient DSP hardwares satisfying performance constraints.

• 한국태양에너지학회:학술대회논문집
• /
• 2011.04a
• /
• pp.138-143
• /
• 2011

Until now, measures for energy saving in buildings have been tried. Because particularly the role of buildings area is very important for implementing national greenhouse gas reduction targets and Green growth. But, lack of business linkages between each sector or the interest and participation of private sector are not enough. In addition, relevant personnel to do had not been systematized. It is expected that certification services will be increased according to the activation of Building Energy Efficiency Rating System and expansion of the target buildings so Government must be prepared to expand of certification system by training Professional staff. In this study, the basic data for the introduction of obligation of Building Energy Efficiency Rating System is suggested through analysis of the operating and laws system of Building Energy Efficiency Rating System along with efforts of Government for diffusion low energy buildings.

• Journal of the Korean Solar Energy Society
• /
• v.30 no.5
• /
• pp.32-37
• /
• 2010

In order to handle the crisis about energy-environment problem, it is necessary to develop the future-oriented and innovative energy technology in architecture area. So the development of new technology for energy saving and alternative energy use has been spurred in this area. Double skin window system, which is an active covering to respond to the exterior change of the environment, is the skill that can reduce the indoor cooling and heating load and the environmental architecture can be realized. This study works out U-value of windows using the window-simulation program with the development and study of the double skin. In addition, the effect of the double skin insulation on the efficiency rating has been analyzed, applying to the certification system of the building energy efficiency rating which has implemented.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.68 no.1
• /
• pp.207-214
• /
• 2019

A large-capacity wireless power system is a technology that transmits electric power of kW or more in a noncontact type. Electric cars, electric buses, and electric railways. In order to increase the power transmission efficiency, a resonance method using a frequency of kHz is applied and the efficiency is 80 ~ 90%. In this case, the loss is 10 ~ 20% other than efficiency, and corresponds to several hundreds of W to several kW in kW class wireless power transmission. 35 kW wireless feed system environment, and induced current in the nearby conductive part was measured. As a result of analysis, it was confirmed that induction phenomenon is higher as the loop configuration of the conductive part per area is dense. The increase of the induced current in the mesh loop is characterized by the density of the nearby conductive part having a permeability per unit area. The concentration of the magnetic field by the permeability is increased and the induction phenomenon causing the induction current is increased. It was confirmed that induction phenomenon increases by about 2.7 times when 9 times dense structure is formed.

• Journal of the Korean Solar Energy Society
• /
• v.25 no.3
• /
• pp.47-52
• /
• 2005

Normally if sunlight is directed on a solar cell without any increasing in temperature, the amount of absorption energy per unit area of each cell is increasing. In a silicon solar cell. however, cell conversion efficiency decreases with the increase of temperature. Therefore, to maintain cell conversion efficiency under normal condition, it is necessary to keep the cell at operating temperature. We tried to design and make new hybrid panel with cooling system to prevent increasing of temperature on cell, collect and use thermal energy more effectively. We compared performance of this new hybrid panel with current thermal panel. We also evaluated conversion efficiency, thermal capacity and confirmed cooling effects from thermal absorption efficiency.

• International journal of advanced smart convergence
• /
• v.11 no.4
• /
• pp.193-205
• /
• 2022

Based on the results of this study, we presented the following policy recommendations to improve the efficiency of operation and management of public cremation facilities. First, we findings the cremation number of all public cremation facilities in Gyeonggi-do increased from 39,918 people before the opening of public cremation facilities in Hwaseong to 55,642 people after the opening, showing a high rate of increase of 15,724 people(39.4%). Therefore, in order to increase the cremation ratio, the policy of expanding the supply of public cremation facilities should be actively pursued. Second, in this study we compared to before the opening of public cremation facilities in Hwaseong City, the ratio of cremation number the jurisdiction area of all public cremation facilities in Gyeonggi-do using the E-Haneul Funeral Information System increased by 19.0% from 35.9% to 54.9% after the opening, whereas it was analyzed that the outside of the jurisdiction area decreased by 19.0% from 64.1% to 45.1%. Therefore, in order to improve the convenience of citizens using the jurisdiction area, priority should be given to the promotion of policies for the establishment of public cremation facilities by local governments that do not have public cremation facilities. Third, through we research it is analyzed that the cremation ratio of the jurisdiction area of the public cremation facilities in Hwaseong City, which was jointly installed by six local governments located in Gyeonggi-do, was 92.4%, indicating that the ratio proportion of cremation number in the area is very high. Therefore, in order to improve the efficiency of the operation of public cremation facilities, the promotion of policies for joint installation and operation of public cremation facilities should be encouraged.

• Journal of the Korean Solar Energy Society
• /
• v.27 no.4
• /
• pp.167-173
• /
• 2007

This study analyzed by simulation using TRNSYS as well as by experiment on the solar district heating system installed for the first time for the district heating system in Bundang. Simulation analysis using TRNSYS focused on the thermal behavior and long-term thermal efficiency of solar system. Experiment carried out for the reliability of simulation system. This solar system where the circuits of two different collectors, flat plate and vacuum tube collector, are connected in series by a collector heat exchanger, and the collection characteristics of each circuit varies. Therefore, these differences must be considered for the system's control. This system uses variable flow rate control in order to obtain always setting temperature of hot water by solar system. Specifically, this is a system that heats returning district heating water (DHW) at approximately $60^{\circ}C$ using a solar collector without a storage tank, up to the setting temperature of approximately $85{\sim}95^{\circ}C$ To realize this, a flat plate collector and a vacuum tube collector are used as separate collector loops. The first heating is performed by a flat plate collector loop and the second by a vacuum tube collector loop. In a gross collector area basis, the mean system efficiency, for 4 years, of a flat plate collector is 33.4% and a vacuum tube collector is 41.2%. The yearly total collection energy is 2,342GJ and really collection energy per unit area ($m^2$) is 1.92GJ and 2.37GJ respectively for the flat plate vacuum tube collector. This result is very important on the share of each collector area in this type of solar district heating system.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2003.09a
• /
• pp.148-151
• /
• 2003

Soil washing was applied as a supplementary step of soil remediation at a petroleum oil contaminated site. A soil washing system was designed, assembled, and operated at the site. A field screening method with PetroFlagTM was adopted at the site to find the exact boundary of contaminated area as soil excavation progressed and to verify the concentration of treated soil. The system operation showed the cleanup efficiency of 90% at the compatible cost compared to other methods.

• Korean Journal of Computational Design and Engineering
• /
• v.20 no.1
• /
• pp.11-21
• /
• 2015

Currently, the United States, the United Kingdom, Australia etc. are actively utilizing energy simulation for efficiency evaluation of building energy. However, domestic energy efficiency assessment system doesn't use energy simulation system properly at present: parameters based architecture plans and Ashrae Standard are inputted for the evaluation, because the input parameters for the simulation haven't been established yet. This fact causes poor reliability during energy simulation, as the values of the two standards are different from each other. Therefore, the aim of the study is to set domestic standard parameter for BIM-based energy performance evaluation, focusing on possession area per person of occupants at government office in Korea. We found that the difference among the result values occurred approximately 3% in the energy simulation. As a result of the analysis, possession area per person of occupants in Government office is $31.87m^2$. Other input parameters may be set based on this. This will increase the reliability of energy simulation through a domestic standard parameter.

• Journal of Wetlands Research
• /
• v.17 no.3
• /
• pp.311-319
• /
• 2015

The Korean government has made progress in its project for sewage distribution in rural areas to ensure the balanced development of the country and its water conservation system. The project for sewage distribution in rural areas was analyzed with the yearly operational results of municipal wastewater treatment plant (MWTP). The sewage characteristics of the MWTP in a rural area changed according to seasonal variations, and the lowest pollution concentrations were obtained in the summer. The treatment efficiency of nutrients in the biological treatment process changed slightly more than the treatment efficiency of organic compounds, and the lowest treatment efficiency was obtained in winter. In addition, the relationship between treatment efficiency and retention time and F/M ratio showed similar results despite seasonal variations. It was considered that sewage characteristics and treatment efficiency changed according to seasonal variations when the treatment process was selected in MWTPs in rural areas. Especially, Maintenance of MWPT is need for the stable treatment efficiency of nutrients in the winter.