• Journal of Korean Society on Water Environment
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• v.30 no.6
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• pp.673-682
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• 2014

A watershed model was constructed using Hydrological Simulation Program Fortran to predict the water temperature at major tributaries of Nakdong River basin, Korea. Water temperature is one of the most fundamental indices used to determine the nature of an aquatic environment. Most processes of an aquatic environment such as saturation level of dissolved oxygen, the decay rate of organic matter, the growth rate of phytoplankton and zooplankton are affected by temperature. The heat flux to major reservoirs and tributaries was analyzed to simulate water temperature accurately using HSPF model. The annual mean heat flux of solar radiation was estimated to $150{\sim}165W/m^2$, longwave radiation to $-48{\sim}-113W/m^2$, evaporative heat loss to $-39{\sim}-115W/m^2$, sensible heat flux to $-13{\sim}-22W/m^2$, precipitation heat flux to $2{\sim}4W/m^2$, bed heat flux to $-24{\sim}22W/m^2$ respectively. The model was calibrated at major reservoir and tributaries for a three-year period (2008 to 2010). The deviation values (Dv) of water temperature ranged from -6.0 to 3.7%, Nash-Sutcliffe efficiency(NSE) of 0.88 to 0.95, root mean square error(RMSE) of $1.7{\sim}2.8^{\circ}C$. The operational water temperature forecasting results presented in this study were in good agreement with measured data and had a similar accuracy with model calibration results.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.10
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• pp.1483-1496
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• 2001

Small ruminants form an important economic and ecological niche in small farm systems and agriculture. Their current low level of contribution is dismal, and is not commensurate with the potential capacity for higher levels of production. The context for productivity enhancement and increased socio-economic contribution relates to large sizes of small ruminant populations; wide distribution across various agro-ecological zones and production systems; and diversity of breeds, where 66% of all goat and 57% of sheep breeds in Asia are found in China, India and Pakistan. The advantages and disadvantages of small ruminants over larger ruminants are enumerated with reference to adaptation and environment, small size, production systems and products and interactions with the environment. Discussion focuses especially on efficiency of meat production and niche markets for higher-priced goat meat, and inefficient marketing systems given an estimated 40-45% loss of income to farmers presently. Increasing the quantity of meat produced is related to live weight and the total number of animals at Slaughter, which in turn, depend on the total number of offsprings weaned and lifetime productivity. At the national level, priority attention is essential to build up numbers in concerted breeding programmes, selection for efficiency of reproduction and meat production, and improvements to make traditional markets and marketing systems to respond to the changing environmental and consumer preferences. Post-production systems are neglected and improvements are associated with collection, handling, marketing, slaughter facilities and consumer requirements. Potential opportunities to expand and benefit from integrating small ruminants into annual and perennial cropping systems remain largely unexplored. Important development imperatives include choice of species and better use of available breeds, appropriate production systems that match available feed resources, and linkages between production, products and by-products to markets. Affirmative action is necessary, backed by official policy support, institutional commitment and increased resource use, that can target poverty and directly benefit the poor, and shift subsistence production to a more market-oriented opportunity. These efforts together constitute the challenges for both the owners and producers of small ruminants in the immediate future, as also the will to accelerate increased productivity, improve their livelihoods and promote rural growth.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3265-3269
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• 2016

Background: Around half of input data in the global burden of disease cancer collaboration (GBD-CC) and GLOBOCAN projects come from low quality sources, mainly from developing countries. This may lead to loss of precision in estimates. Our question was: Are the absolute values and trends of the GBD-CC and GLOBOCAN estimates for lung cancer (LC) in Iran consistent with available statistics?. Materials and Methods: Incidence and mortality statistics were extracted from national reports (N.IRs & N.MRs) and GBD-CC (GBD-incidence & mortality) and GLOBOCAN databases for 1990-2013 where available. Trends were analyzed and absolute values and annual percentage changes (APCs) were estimated and compared. Incompleteness of case ascertainment at the Iranian national cancer registry and Iranian national civil registration was assessed for better understanding. Results: Trends of N.IRs were significantly rising for males (APC: 19.4; 95% CI: 12.5-26.7) and females (23.2; 16.0-30.8). Trends of GBD-incidence were stable for males (-0.2; -1.5-1.1) and females (-1.0; -2.3-0.4). Absolute N.IRs were less than GBD-incidence steadily except for 2009. Trend of N.MRs was increasing up to 2004, but stable thereafter. Trends of GBD-mortality were also stable. Absolute N.MRs were less than GBD-mortality for years up to 2003 and more than GBD-mortality since 2005. The estimates of GLOBOCAN were more than N.IRs and N.MRs. Conclusions: The GBD-CC and GLOBOCAN values for LC in Iran are underestimates. Generation of data quality indices to present along with country specific estimates is highly recommended.

• Clinical and Experimental Pediatrics
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• v.63 no.8
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• pp.284-290
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• 2020

Korea currently has the world's lowest birth rate but a rapidly inreasing number of preterm infants. The Korean Neonatal Network (KNN), launched by the Korean Society of Neonatology under the support of Korea Centers for Disease Control, has collected population-based data for very low birth weight infants (VLBWIs) born in Korea since 2013. In terms of the short-term outcomes of VLBWIs born from 2013 to 2016 registered in the KNN, the survival rate of all VLBWIs was 86%. Respiratory distress syndrome and bronchopulmonary dysplasia were observed in 78% and 30% of all VLBWIs, respectively. Necrotizing enterocolitis occurred in 7%, while 8% of the VLBWIs needed therapy for retinopathy of prematurity in the neonatal intensive care unit (NICU). Sepsis occurred in 21% during their NICU stay. Intraventricular hemorrhage (grade ≥III) was diagnosed in 10%. In terms of the long-term outcomes for VLBWIs born from 2013 to 2014 registered in the KNN, the post-discharge mortality rate was approximately 1.2%-1.5%, mainly owing to their underlying illness. Nearly half of the VLBWIs were readmitted to the hospital at least once in their first 1-2 years of life, mostly as a result of respiratory diseases. The overall prevalence of cerebral palsy was 6.2%-6.6% in Korea. Bilateral blindness was reported in 0.2%-0.3% of VLBWIs, while bilateral hearing loss was found in 0.8%-1.9%. Since its establishment, the KNN has published annual reports and papers that facilitate the improvement of VLBWI outcome and the formulation of essential healthcare policies in Korea.

• Korean Journal of Ecology and Environment
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• v.51 no.1
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• pp.135-147
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• 2018

In order to investigate the runoff characteristics of nonpoint source pollutants in the Lake Doam watershed, water quality and flow rate were monitored for 38-rainfall events from 2009 to 2016. The EMC values of SS, COD, TN and TP were in the range of 33~2,169, 3.5~56.9, 0.09~7.65 and $0.06{\sim}2.21mg\;L^{-1}$, respectively. As a result of analyzing the effect of rainfall factor on the nonpoint source pollutant load, EMCs of SS, COD and TP showed a statistically significant correlation with rainfall (RA) (p<0.01) and SS showed highly significant correlation with maximum rainfall intensity (MRI, R=0.48). The load ranges of SS, COD, TN and TP were 10.4~11,984.6, 1.1~724.4, 0.6~51.6 and $0.03{\sim}22.85ton\;event^{-1}$, respectively, showing large variation depending on the characteristics of rainfall events. The effect of rainfall on the load was analyzed. SS, COD and TP showed a positive correlation, but TN did not show any significant correlation. The annual load of SS was the highest with $88,645tons\;year^{-1}$ in 2011 when rainfall was the highest with 1,669 mm. The result of impact analysis of nonpoint source pollution reduction project and land-use change on runoff load showed that pollutant load significantly reduced from 2009 to 2014 but SS and TP loads were increased from 2014 to 2016 due to increase in construction area. Therefore, we suggested that nonpoint source pollution abatement plan should be continued to reduce the soil loss and pollutants during rainfall, and countermeasures to reduce nonpoint source pollution due to construction need to be established.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.241-246
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• 2005

Doam watershed is located at alpine areas in the Kangwon province. The annual average precipitation, including snow accumulation during the winter, at the Doam watershed is significantly higher than other areas. Thus, pollutant laden runoff and sediment discharge from the alpine agricultural fields are causing water quality degradation at the Doam watershed. To estimate soil erosion from the agricultural fields, the Universal Soil Loss Equation (USLE) has been widely used because of its simplicity to use. The USLE rainfall erosivity (R) factor is responsible for impacts of rainfall on soil erosion. Thus, use of constant R factor for the Doam watershed cannot reflect variations in precipitation patterns, consequently soil erosion estimation. In the early spring at the Doam watershed, the stream flow increases because of snow melt, which results in erosion of loosened soil experiencing freezing and thaw during the winter. However, the USLE model cannot consider the impacts on soil erosion of freezing and thaw of the soil. Also, it cannot simulate temporal changes in USLE input parameters. Thus, the Soil and Water Assessment Tool (SWAT) model was investigated for its applicability to estimate soil erosion at the Doam watershed, instead of the widely used USLE model. The SWAT hydrology and erosion/sediment components were validated after calibration of the hydrologic component. The $R^2$ and Nash-Sutcliffe coefficient values are higher enough, thus it was found the SWAT model can be efficiently used to simulate hydrology and sediment yield at the Doam watershed. The effects of snow melt on SWAT estimated stream flow and sediment were investigated using long-term precipitation and temperature data at the Doam watershed. It was found significant amount of flow and sediment in the spring are contributed by melting snow accumulated during the winter. Thus, it is recommend that the SWAT model capable of simulating snow melt and long-term weather data needs to be used in estimating soil erosion at alpine agricultural land instead of the USLE model for successful soil erosion management at the Doam watershed.

• Korean Journal of Poultry Science
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• v.34 no.4
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• pp.301-318
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• 2007

Marek's disease (MD) is a highly contagious lymphoproliferative disease of poultry caused by the oncogenic herpesvirus designated Marek's disease virus (MDV). MD has a worldwide distribution and is thought to cause an annual loss over US$ one billion to the poultry industry. Originally described as a paralytic disease, today MD is mostly manifested as an acute disease with tumors in multiple visceral organs. MD is controlled essentially by the widespread use of live vaccines administered either in ovo into 18-day-old embryos or into chicks immediately after they hatch. In spite of the success of the vaccines in reducing the losses from the disease in the last 30 years, MDV strains have shown continuous evolution in virulence acquiring the ability to overcome the immune responses induced by the vaccines. During this period, different generations of MD vaccines have been introduced to protect birds from the increasingly virulent MDV strains. However, the virus will be countered each new vaccine strategy with ever more virulent strains. In spite of this concern, currently field problem from MD is likely to be controled by strategy of using bivalent vaccine. But, potential risk factors for outbreak of MD are still remained in this condition. The major factors can be thought that improper handling and incorrect administration of the vaccine, infection prior to establishment of immunity, suppression of immune system by environmental stress and outbreaks of more virulent MDV strain by using vaccine and genetic resistance of host.

• International Journal of Concrete Structures and Materials
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• v.3 no.1
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• pp.15-23
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• 2009

Over about 30% of problems in construction is related to water-leaking, and the loss from this problem can incur as much as three times the cost of initial construction. Thus, water vapor pressure is known to be the primary cause of defective waterproofing. Accordingly, the theories on the relationship between water pressure and temperature as well as damp-proofing volume of concrete and the change in vapor pressure volume were reviewed and analyzed in this study by making test samples after spraying a dampness remover and applying waterproofing materials to the prepared test specimens. The result of measuring water vapor pressure with the surface temperature of the waterproofing (fluid-applied membrane) layer at the experimental temperature setting of about $10^{\circ}C$, which is the annual average temperature of Seoul, indicated that (1) the temperature of the fluid-applied membrane elevated to about $40^{\circ}C$, and the water vapor pressure generated from the fluid-applied membrane was about 0.03 N/mm 2 when the surface temperature of the waterproofing layer was raised to about $80^{\circ}C$. (2) when the temperature of the fluid-applied membrane of the waterproofing layer was raised from $30^{\circ}C$ to $35^{\circ}C$, water vapor pressure of about 0.01 N/mm 2 was generated, and (3) when a thermal source was applied to the fluid-applied membrane (waterproofing) layer, the temperature increased from $35^{\circ}C$ to $40^{\circ}C$, and approximately $0.005\;N/mm^2$ of water vapor pressure was generated.

• Journal of Plant Biology
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• v.28 no.2
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• pp.119-126
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• 1985

The productivity and growth pattern of Sargassum confusum (Phaeophyta, Sargassaceae) was investigated in Ohori, east coast of Korea, from March 1983 to April 1984. S. confusum shows an obvious seasonal variation of the growth by passing through the germinative, vegetative, reproductive and decaying phases for about an year. The mean length of tagged individuals shows a positive correlation with the water temperature during the growing period. The growth is depressed at less than 1$0^{\circ}C$ in February, and accelerated at above 15$^{\circ}C$ in May. The rapid growth (1.29 cm/dry) occurs at 15-l8$^{\circ}C$ during May-June and the maximum length is shown at 20-21$^{\circ}C$ in early August. Daily net production estimated by the oxygen light and dark bottle method is 11.2 g C/$m^2$/ day in June. The annual value calculated by the integration of the daily net production, growth rate and biomass is 745 gC/$m^2$/yr. Net production estimated from the biomass change only is 287 gC/$m^2$/yr. But this must be an underestimated value, because the loss of considerable biomass by shedding is not included.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.12
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• pp.1682-1688
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• 2017

In modern society, the number of industrial customers using equipment sensitive particularly to voltage sags is rapidly increasing. As voltage sags can cause loss of information as well as false operation of the control device, it results in the vast economic damage in industrial processes. One way to mitigate voltage sags in the sensitive loads is the installation of distributed generation (DGs) on the periphery of these loads. In addition, renewable energy sources are currently in the spot light as the potential solution for the energy crisis and environmental issues. In particular, wind power generation which is connected to a grid is rising rapidly because it is energy efficient and also economically feasible compared to other renewable energy sources. On the basis of the above information, in this paper, with Wind Turbine Generators (WTGs) installed nearby the sensitive load, the analysis of the mitigating effect comparison by types of WTGs is performed using voltage sag assessment on the IEEE-30 bus test system. That is, the areas of vulnerability according to types of WTGs are expected to be different by how much reactive power is produced or consumed as WTG reactive power capability is related to the types of WTGs. Using the concept of 'Vulnerable area' with the failure rate for buses and lines, the annual number of voltage sags at the sensitive load with the installation of WTGs per type is studied. This research will be anticipated to be useful data when determining the interconnection of wind power generation in the power system with the consideration of voltage sags.