• Journal of Korea Water Resources Association
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• v.40 no.7
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• pp.555-570
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• 2007

The effects of climatic changes owing to urbanization on annual water balance have been studied. In this study, 56 meteorological stations including Seoul metropolis in South Korea have been selected, and the area of study site is $314\;km^2$. The meteorological station is centrally located in the study area with a 10 km radius. Land use status of study area was examined to estimate the urbanization extent, so that annual actual evapotranspiration could be estimated. Annual runoff was estimated by annual water balance approach using the estimated annual actual evapotranspiration and measured annual precipitation. Annual actual evapotranspiration was estimated by applying experimental equation suggested by Zhang et al, (2001) which was evaluated from 250 watersheds all over the world. Study results show that reference evapotranspiration is tending upwards due to urbanization; therefore, it seems that climatic change due to urbanization may increase the amount of annual actual evapotranspiration. However, the increase of residential area due to urbanization in study area may decrease the amount of annual actual evapotranspiration. The study results indicate that urbanization effect on annual trend of precipitation was not significant. In urban area, annual runoff is directly affected by annual precipitation, and compared with annual precipitation, annual variation of actual evapotranspiration was not significant even though it was estimated by using annual precipitation. It seems that the effect of urbanization on annual actual evapotranspiration does not influence on annual runoff significantly, and that urbanization effect on annual runoff Is not significant.

• Weed & Turfgrass Science
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• v.2 no.2
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• pp.122-130
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• 2013

The object of this study is to review the current states of the characteristics and strategies to control annual bluegrass to apply information to the circumstance of South Korea. Annual bluegrass is one of the most widespread turfgrass species which has great ability to produce seedhead and shoot growth. It also has ability to tolerate low mowing height and to form uniformity of turfgrass when it is established. Annual bluegrass is well-known as weak turfgrass for high and low temperature. High rate of nitrogen and phosphorus improves growth of annual bluegrass. To control annual bluegrass, deep and infrequent irrigation is more effective than light and frequent irrigation. Clipping removal is more effective than clipping return to control annual bluegrass. Prodiamine, bensulide, and dithiopyr are applied as pre-emergence herbicide, and ethofumesate and bisbyribac-sodium are used as post-emergence herbicide. Paclobutrazol and flurprimidol are used as plant growth regulator. Trinexapac which is one of the most popular plant growth regulators (PGRs) in South Korea is not proper to control annual bluegrass because it accelerates improve growth of annual bluegrass in summer. Although chemical control is mainly used in South Korea, combination of cultural and chemical control may be the strategy to maximize effectiveness to control annual bluegrass.

• Journal of Korea Water Resources Association
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• v.43 no.5
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• pp.483-493
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• 2010

In this study, for the purpose of analyzing variability and periodicity of Korean hydrologic weather parameters, 5 hydrologic weather parameters data such as annual precipitation, annual rainy days, annual average temperature, annual average relative humidity, annual duration of sunshine are collected from 63 domestic meteorological stations that has the hydrologic weather parameters records more than 30 years. And in this study the variability and periodicity using the statistical methods like Wald-Wolfowitz test, Mann-Whitney test, and Wavelet Transform about hydrologic weather parameters is analyzed. The results of statistical analysis of variability and periodicity can be summarized as follows: 1) Variability commonly appeared in annual average temperature and annual average relative humidity. 2) Annual precipitation, annual rainy days and annual duration of sunshine showed different results according to area. 3) Periodicity appeared in annual precipitation and annual rainy days but did not appeard in annual average temperature, annual average relative humidity and annual duration of sunshine.

• Journal of the Korean Society of Food Culture
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• v.17 no.3
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• pp.225-239
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• 2002

This is the research on the observing annual customs, the annual custom foods and the application of the annual custom foods to the school foodservice. We sample 419 housewives live in Kyungnam area and 174 dieticians work at the primary and secondary schools. Annual customs the housewives and dieticians observe at high degree are Chuseok, Seolral, Jeongwoldaeboreum, Dongji, Chopail, Sambok etc. The housewives observe more Seolral, Chuseok and Dongji than the dieticians and the dieticians observe more Sambok than the housewives.(P<.001) When they provide school foodservice, the dieticians observe Dongji at the highest degree. In Kyungnam they eat most the gakjongnamul as annual custom foods on Chuseok and Seolral. They eat most ogokbap and mugeunnamul on Jeongwoldaeboreum, minarinamul on Chopail, and samgyetang on Sambok and patjuk on Dongji as the annual custom foods. Most of dieticians (94.3%) answer that it is good to provide annual custom foods as the school foodservice on annual customs. However, they indicate some practical problems to do such as inadequacy of the school cooking facilities, its not suiting students' tastes, etc. The rate of housewives' answers that we have to transmit annual customs is higher than that of dieticians.(P<.001) Seolral topped the list of annual customs both housewives and dieticians answer must be transmitted, followed by Chuseok, Jeongwoldaeboreum, Dongji. Dongji is followed by Chopail(P<.001) in the housewives' answers while Sambok(P<.001) in the dieticians' answers. Though most of the respondents know the origins, dates and details of annual customs they think must be transmitted, they don't know well those of the other ones. By their mothers both housewives and dieticians have come to know about annual customs and mostly affected. Secondly housewives affected by their mothers-in-law while dieticians by their school education.(P<.001)

• Proceedings of the Turfgrass Society of Korea Conference
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• 2002.02a
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• pp.3-5
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• 2002

This study was carried out to get better understandings about morphological, ecological, and genetical characteristics of annual bluegrass collected from different golf courses in Korea and eventually to establish a successful control strategy. Twenty five local lines of annual bluegrass collected from 20 golf courses in Korea were classified into annual or perennial type on the basis of morphological characteristics. Twelve local lines showing obvious morphological differences were selected and then genetically assessed using RAPD analysis. Classification of the 12 local lines through RAPD analysis were considerably similar to that determined by both of morphological differences and phenotype. Responses of the two types of annual blugrass to herbicides were also examined. Shoot growth of annual bluegrass was significantly suppressed by flazasulfuron and the annual type was more susceptible than perennial type, regardless of flazasulfuron concentrations used. By pendimethalin treatment, there was no clear difference in susceptibility between the two types of annual bluegrass. However, by the treatment of dithiopyr, annual type was more sensitive than perennial type in both shoot and root growth. Nine tree species were screened to detect their allelopathic potential on turfgrasses and annual bluegrass. Acacia (Robinia pseudo-acacia) leaves showed selective inhibition in the shoot and root growth as well as their seed germination when treated with 2% and 10%(v/v) of the extract. However, the other leaf extracts except acacia inhibited non-selectively the growth of three turfgrass species such as bentgrass, perennial ryegrass and zoysiagrass and annual bluegrass. The PAL activities of annual bluegrass increased at 24 h after treatment of acacia leaf extract and peaked at 36 h and then decreased till 60h. The highest PAL activity was observed at 36h after treatment of 10%. The highest activity of CA4H in annual bluegrass was observed at 2h after treatment of acacia extract and the level was 4 times greater than that of the control. The phenolic acids such as p-coumaric acid, salicylic acid and ferulic acid were increased with the treatment of acacia leaf extract. The chloroplast membrane and cell wall of annual bluegrass were destroyed by treatment of acacia leaf extract and its inner materials were released. The membranes in annual bluegrass cells might be destroyed by phytotoxic compounds from acacia leaf extract.

• Journal of Ecology and Environment
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• v.36 no.1
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• pp.31-38
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• 2013

Annual ring formation is considered a source of information to investigate the effects of environmental changes caused by temperature, air pollution, and acid rain on tree growth. A comparative investigation of annual ring growth of Cryptomeria japonica in relation to environmental changes was conducted at two sites in southern Korea (Haenam and Jangseong). Three wood disks from each site were collected from stems at breast height and annual ring growth was analyzed. Annual ring area at two sites increased over time (p > 0.05). Tree ring growth rate in Jangseong was higher than that in Haenam. Annual ring area increment in Jangseong was more strongly correlated with environmental variables than that in Haenam; annual ring growth increased with increasing temperature (p < 0.01) and a positive effect of $NO_2$ concentration on annual ring area (p < 0.05) could be attributed to nitrogen deposition in Jangseong. The correlation of annual ring growth increased with decreasing $SO_2$ and $CO_2$ concentrations (p < 0.01) in Jangseong. Variation in annual growth rings in Jangseong could be associated with temperature changes and N deposition. In Haenam, annual ring growth was correlated with $SO_2$ concentration (p < 0.01), and there was a negative relationship between precipitation pH and annual ring area (p < 0.01) which may reflect changes in nutrient cycles due to the acid rain. Therefore, the combined effects of increased $CO_2$, N deposition, and temperature on tree ring growth in Jangseong may be linked to soil acidification in this forest ecosystem. The interactions between air pollution ($SO_2$) and precipitation pH in Haenam may affect tree growth and may change nutrient cycles in this site. These results suggested that annual tree ring growth in Jangseong was more correlated with environmental variables than that in Haenam. However, the further growth of C. japonica forest at two sites is at risk from the long-term effects of acid deposition from fossil fuel combustion.

• Journal of Korea Water Resources Association
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• v.43 no.4
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• pp.409-419
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• 2010

In this study, for the purpose of analyzing the characteristics of Korean hydrologic weather parameters, 9 hydrologic weather parameters data such as annual precipitation, annual rainy days, annual average relative humidity, annual average temperature, annual duration of sunshine, annual evaporation, annual duration of precipitation, annual snowy days and annual new snowy days are collected from 63 domestic meteorological stations that has the hydrologic weather parameters records more than 30 years. And the basic characteristics of hydrologic weather parameters through basic statistics, moving average and linear regression analysis are perceived. Also trend using the statistical methods like Hotelling-Pabst test and Mann-Kendall test about hydrologic weather parameters is analyzed. Through results of basic analysis, moving average and linear regression analysis it is shown that precipitation is concentrated in summer and deviation of precipitation for each season showed significant difference in accordance with Korean climate characteristics, besides the increase in annual precipitation and annual average temperature, annual average relative humidity and annual duration of sunshine reduction and annual rainy days is said to increase or decrease. The results of statistical analysis of trend are summarized as trend commonly appeared in annual average relative humidity and annual average temperature. and annual precipitation, annual rainy days and annual duration of sunshine showed different results according to area.

• Water Engineering Research
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• v.5 no.4
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• pp.185-193
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• 2004

Estimates of annual actual evapotranspiration are needed in water balance studies, water resources management projects, and many different types of hydrologic studies. This study validated a set of 5 empirical equations of estimating annual actual evapotranspiration with climate data on 11 watersheds, and evaluated the further applicability of these forms in estimating annual runoff on watershed level. Five empirical equations generally overestimated annual evapotranspiration, with relative errors ranging $3.3\%$ to $47.2\%$. The results show that Schreiber formula can be applicable in determining annual evapotranspiration in sub-humid region that is classified by aridity index, while Zhang equation gave better results than the remaining methods in humid region. The mean differences for annual evapotranspiration bias over 11 watersheds are Zhang, Schreiber, Budyko, Pike, and Ol'dekop formula from lowest to highest. The empirical equations provide a practical tool to help water resources managers in estimating regional water resources on ungauged large watershed.

• International Journal of Air-Conditioning and Refrigeration
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• v.6
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• pp.1-13
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• 1998

The basic heat transfer process that occurs in a building can best be illustrated by an electrical circuit network. Present paper reports the dynamic simulation of annual energy consumption in an office building by the thermal resistance capacitance network method. Unsteady thermal behaviors and annual energy consumption in an office building were examined in detail by solving the simultaneous circuit equations of thermal network. The results are used to evaluate the accuracy of the modified BIN method for the energy consumption analysis of a large building. Present thermal resistance-capacitance method predicts annual energy consumption of an office building with the same accuracy as that of response factor method. However, the modified BIN method gives 15% lower annual heating load and 25% lower cooling load than those from the present method. Equipment annual energy consumptions for fan, boiler and chiller in the HVAC system are also calculated for various control systems as CAV, VAV, FCU+VAV and FCU+CAV. FCU+CAV system appears to consume minimum annual energy among them.

• Journal of Family Resource Management and Policy Review
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• v.16 no.4
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• pp.131-152
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• 2012

The aims of this study were to analyze middle-aged households' financial preparation for retirement. Specifically, this study surveyed the relation between human capital investment for children and the middle-aged households' financial preparation for retirement and investigated factors influencing financial preparation for retirement. Data were obtained from the 3rd Korean Retirement and Income Study (KReIS) in 2009, and a sample of 757 households was selected. The statistical methods were frequency, percentile, mean, standard deviation, ${\chi}^2$, t-test, Pearson's correlation coefficient, and logistic regression analysis. The findings of this study are as follows. First, the percentile of preparation for living costs for old age was 49.9% for the middle-aged households. In terms of the types of preparation for living costs for old age, the results showed 61.6% of personal preparation, 33.9% of pension system, and 1.3% for children and relatives. In relation to the adequacy of the preparations for living costs for old age, preparations made by 57.4% of the middle-aged households were inadequate. Observing the minimum living costs for old age and adequate living costs after retirement for single and couple, the minimum living costs of the middle-aged households was 1.46 million won for couple and 0.91 million won for single. The adequate living costs for old age was 2.07 million won for couple and 1.34 million won for single. Second, there were 757 households with total education expenditure. Of these, 208 incurred annual expenditure on public education, and the annual expenditure for public education was 7.28 million won. There were 170 households with annual expenditure for private education, and the annual expenditure for private education was 2.50 million won. 243 households of middle-aged households had annual expenditure for human capital investment, including both public and private education, with annual expenditure for human capital investment for children of 7.82 million won. Furthermore, in the human capital investment factor, there was a difference in the middle-aged households' financial preparation for retirement according to their annual expenditure for human capital investment including both public and private education. In addition, there was a difference in financial preparation for retirement based on their public education expenditure. Third, in the logistic regression model 1, which included human capital investment, the significant variables affecting the preparation for retirement of the middle-aged households were as follows : annual household income, total amount of annual household income, experience of inadequate living costs, existence of financial assets, total amount of annual household savings, financial independence, adequate living costs (for single) for old age, and human capital investment. In the logistic regression model 2, which included annual expenditure for public education and annual expenditure for private education, the significant variables affecting the preparation for retirement of the middle-aged households were as follows : annual household income, total amount of annual household income, experience of inadequate living costs, existence of financial assets, total amount of annual household savings, financial independence, adequate living costs (for single) for old age, and annual expenditure for public education.