• Water for future
• /
• v.13 no.1
• /
• pp.49-56
• /
• 1980

The thesis of this analytical study includes 1) the generation of annual and monthly discharge regarding single hydrological variable at single site, 2)comparsion with the historical records and the generation, and 3) changing the monthly generatied discharge into annual. The conclusion of this will be used for the future plan for water resources development. Annual discharges at waegwan are characterized by log-normal distirbution and persistence-absent. Also, the random number generator causes the errors in the generation of annual discharge. The serial correlation coefficients of the generated annual discharge have less value than that of historical records, while the correlation coefficient and slope in January have(+) value and opposite to historical record. To change the monthly generated discharge into annual is not proper.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.66 no.4
• /
• pp.605-612
• /
• 2017

One of the biggest environmental issues that our world has been facing is climate change. In order to cope with such environmental issues, the world is putting a great deal of effort into energy conservation. The building sector, in particular, consumes 36% of the energy consumed worldwide and emits considerable amount of greenhouse gases. Therefore, introduction of renewable energies in the building sector is highly recommended. Renewable energy sources that can be utilized in the building sector include sunlight, solar heat, geothermal heat, fuel cells and wind power. The wind power generation system which converts wind energy into electrical energy has advantages in that wind is an unlimited and pollution-free resource. It is suitable to be connected to existing buildings because many years of operational experience and the enhanced stability of the system have made it possible to downsize the electrical generator. In case of existing buildings, it is necessary to consider the live loads of the buildings to connect the wind power generation system. This paper, through the connection of the wind power generation with existing buildings, promotes reduction of greenhouse gas emissions and energy independence by reducing energy consumption in the building sector. In order to connect the wind power generation system with an exciting building, the live load of the building and the area of the rooftop should be considered. The installable model is selected by comparing the live load of the building and the load of the wind power generation system. The maximum number of the wind turbines that can be installed is obtained by considering the separation distance between the wind turbines within the area of the rooftop. Installations are divided into single installations and multiple installations of two different types of wind turbines. After determining the maximum installable number, the optimal model that can achieve the maximum annual power generation will be selected by comparing the respective total annual amount of the power generation of different models.

• Journal of the Architectural Institute of Korea Structure & Construction
• /
• v.35 no.5
• /
• pp.169-179
• /
• 2019

During the initial design stage of apartment complex, the photovoltaic(PV) system has been considered as an alternative of renewable energy system and planned to install at the rooftop floor level in general. The electric power generation characteristics can be influenced by the block layout, building orientation and roof top structure because of azimuth angle, tilt angle, and partial shading. This study aims to investigate power generation characteristics of photovoltaic system in apartment buildings by considering the partial shading conditions due to the block layout, building orientation and roof-top structures. For the photovoltaic module arrangement planning in rooftop floor level, shading areas were firstly analyzed due to the adjacent building structure. And the annual and seasonal power generation of PV system were analyzed through the PVsyst simulation results. The results show that shading period at the roof top surface can be increased due to the parapet and water tank. Initial design power capacity can be decreased by considering the daily insolation period and distance between PV modules through the shading simulation. As the number of PV modules decreases, the annual power generation can be decreased. However annual power generation per unit area of PV modules can be increased and performance ratio can be increased above 80%. Also the power generation of PV system can be critically affected by building orientation and the performance ratio can be drastically decreased in east-oriented buildings due to the shading problems caused by adjacent structures at roof top level such as parapet and water tank.

• Journal of Environmental Science International
• /
• v.11 no.6
• /
• pp.537-541
• /
• 2002

This study aimed to obtain the relative formula with the unit treatment cost according to the treatment of a sewage plant in the service area under highway. The following results were obtained. The correlative formula connected to amount of sewage(Q)generation was as follows ; between an annual amount of sale(C) showed Q=19.113$.$C$\^$0.9294/, and between the number of users(P) showed Q=2${\times}$10$\^$-8/ $.$P$^2$- 0.0298$.$P + 75,666. The correlative formula connected to the treatment cost was as follows , according to the amount of sewage generation showed S= 3${\times}$10$\^$-6/$.$Q 0-0.2266$.$Q+29,895, according to the elimination of BOD(E) showed S=6${\times}$10$\^$-5/$.$E$^2$-0.6717$.$E + 27,744, according to the annual amount of sale showed S=0.0005 C$^2$-4.8013$.$C + 35,118, with the number, of persons(P) using the service area showed S= 2${\times}$10$\^$-8/ $.$P$^2$- 0.046$.$P + 48,803.

• Korean Journal of Poultry Science
• /
• v.9 no.1
• /
• pp.35-42
• /
• 1982

Data pertaining to the first generation of a Synthetic White Leghorn flock were used to estimate the heritabilities of and genetic correlation between partial egg production(egg number or percentage) or diversely segmented part records and other traits such as age at sexual maturity, residual and annual egg production, and to compare the expected genetic gain from selection on partial egg number or partial percent production with correlated response in other traits. The estimated heritabilites for six measures of egg Production were ranged from 29 to 35, while heritability for age at sexual maturity (SM) was intermediate (48). Genetic correlations between partial egg number (P) and annual egg number. (A), and partial percent production (P') and annual percent production (A') were 51 and 72, respectively. Genetic correlation between P and SM was estimated largely negative (-.64), while correlation bettween P' and SM was positively intermediate(34). In comparing direct response from selection on partial production (P or P') with another response in correlated trait, selection on P would be 25% more efficient than selection of P' for improving A, while selection of P' would be 94% more efficient than selection P for improving A' For shortening SM selection of P would be 98% more efficient than selection on P'.

• Asia-Pacific Journal of Business
• /
• v.13 no.3
• /
• pp.389-400
• /
• 2022

Purpose - This study empirically analyzes the effects of food delivery service use frequency and the proportion of single-person households on the generation of MSW (Municipal Solid Waste). Additionally, the study analyzes MSW increase during the COVID-19 period. Design/methodology/approach - The study uses annual information on MSW and related characteristics of 228 Si, Gun, and Gu, which are administrative districts of Korea, from 2015 to 2020. Panel fixed effect model is employed for estimations. Findings - The study finds that food delivery and single-person household have significant effects only on recyclable and standard garbage bag MSW, respectively, not on all produce types of MSW. Additionally, it is estimated that, during the COVID-19 period, the increasing effect of food delivery is intensified while single-person households diminish its increasing effect. Lastly, the study confirms that the marginal effect on the increasing effect of MSW generation by the number of household members. Research implications or Originality - The estimated results are expected to provide useful information for the related policies. In particular, it is necessary to focus more on recyclable MSW concerning the developing delivery culture, and regarding changes in the family structure, focus more on the number of household members than single-person households.

• Korean Journal of Agricultural Science
• /
• v.42 no.4
• /
• pp.305-311
• /
• 2015

In this research, we surveyed the yield change of garlic cultivation with seed bulbs according to annual field culture after induced meristem culture. From 2007 to 2013, yearly produced seed bulbs from $2^{nd}$ to $8^{th}$ generation were cultivated in the Muan field. Over the generations, the general growth characteristics such as the plant height, leaf number, leaf length and stem diameter were all decreased. When we compared the conventional seed bulbs and TCR ones, the plant height and stem diameter showed bigger difference. And the TCR seed bulbs showed a week late harvest time against the conventional ones. The yield of $2^{nd}$ generation was 72.3 g and 57.1 g for the $8^{th}$ generation. However every generation showed higher yield than conventional seed garlic's ones as 43.9 g. The yield index showed the same trend as $2^{nd}-8^{th}$ to 63% to 21%. After the tissue culture of garlics, the viral infections (OYDV and GSV) of TCR was far less than that of conventional ones. In case of LYSV, the infection ratio was 6.7% at $2^{nd}$ generation and 26% at $8^{th}$. However, the ratio was far less than that (80%) of the conventional ones.

• Journal of the Architectural Institute of Korea Structure & Construction
• /
• v.35 no.4
• /
• pp.185-192
• /
• 2019

In this study, we, through case studies, formulated a method to implement net-zero energy daycare center at the current insulation and technology level, and calculated its energy expense. The reference model was a medium sized daycare center whose number of children was 99. We analyzed the energy consumption status for the reference model and developed TRNSYS simulation analytical model to realize net-zero energy . We assumed the reference model to be "All Electric Building" where all energy including cooking is supplied by electricity. The result is summarized as follows: First, the annual electricity consumption of daycare center was 53,291kWh. Plug load occupied the largest share of 48% followed by lighting, 10%, cooling, 9%, cooking, 9%, heating, 8%, hot water, 5% and ventilation, 2%. Second, the photovoltaic installation capacity to realize net-zero energy was 40.32kWp and its annual generation was 53,402kWh. Third, the annual energy expense(electricity bill) by realizing net-zero energy was 2,620,390won.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.5
• /
• pp.680-687
• /
• 2018

Because of its predictability of the energy cycle and huge scale power output, the ocean energy from tidal power utilization has always received attention as a great energy source, even though its development cost, including the embankment construction, is so much higher than that of any other energy source. Nevertheless, nowadays many projects are being planned on account of institutional support from the government and the recent advance of construction technology. In Korea, the new industry field operating and managing the tidal power plant has already opened. But we are facing a number of problems for optimal operation of tidal power plant that are a lack of operation experience and a skill of professional management and others. This paper suggests a novel way to determine the starting head of power generation by generating power comparison method For this new method, the paper discusses many factors including changing the volume of the basin, the number of operating turbines and gates and forecasting the tidal amplitude and the characteristic curve of turbine and gate. Finally we verified that it can increase about 2% an annual power generation compared with the conventional method using the original operational function made in the plant design process.

• Korean journal of applied entomology
• /
• v.62 no.4
• /
• pp.227-243
• /
• 2023

The Asiatic pink stem borer, Sesamia inferens (Walker, 1856) (Lepidoptera: Noctuidae) is a pest that attacks rice stems. In this study, we estimated the annual generation of insect in several regions of the Republic of Korea. Adult trapping using a sex pheromone trap detected the occurrence of S. inferens adults in the three northernmost areas around 38° latitude and showed that the insect inhabits all of Korea. In most areas investigated, the seasons of the adult generations estimated using the single-sine degree-day model did not deviate from the corresponding observed seasons of adult occurrence. We estimated that the overwintering larvae hypothetically-estimated using the model could be originated from the last generation of adults. When larvae collected in paddy fields during the autumn season in a few middle and southern areas were reared at 25℃, ca. 70% of pupae did not show additional larval molting before their pupation. All larvae collected in early March in a southern area (Goseong, Gyeongsangnam-do) pupated without additional larval molting when reared at 25℃. Based on these results, we presumed that S. inferens could overwinter as mainly the last instar larval stage in the area. Taken together, we conclude that S. inferens primarily has two generations per year in areas around 38° latitude, and three generations in the areas between 35.3° and 37.3° latitude. In addition, approximately 35% of insects captured by the sex pheromone trap were species other than S. inferens, as determined by analyzing the nucleotide sequences of the cytochrome c oxidase 1 gene. These species were not morphologically misidentified as S. inferens.