• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.174-179
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• 1985

Estimate of heritabilities, genotypic and phenotypic correlations and path coefficient analysis were performed for the seven characters of barley cultivars (Hordeum vulgare L.). Heritabilities of broad sense for stem length and spike length were 0.923 and 0.907. Kernels per spike, grain yield and 100 grain weight also showed high heritabilities. High genotypic and phenotypic correlations existed between stem length and 100 grain weight. Grain yield showed highly significant phenotypic correlation with spike length, 100 grain weight and kernels per spike. Genotypic correlations between those characters were moderately high. Number of stem had greatest direct effect but the number of spike had a strong negative direct effect upon grain yield. Kernels per spike via number of spike showed greatest indirect effect and the number of stem via number of spike showed strong negative indirect effect upon grain yield.

• School Mathematics
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• v.9 no.2
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• pp.241-257
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• 2007

The study aims to figure out how to improve existing examination tools to distinguish mathematically gifted children and to clarify procedures and criteria for selecting candidates. Toward this end, it examined correlations between grades of gifted children selected through evaluation by pen-and-pencil tests and their creative problem-solving capability and performance assessment, and analyzed learning activities of the gifted children. According to the analysis, results of pen-and-pencil tests turned out to have low correlations with their creative problem-solving capability and performance assessment, but it was found that their creative problem-solving capability has high correlations with results of performance assessment. The analysis also found that there were some students who participated in a program for gifted children with high marks but had difficulties in adapting themselves to it. It found that there were children who joined the program with low marks but emerged as successive performers later on. In this regard, the existing examination tools to tell the gifted students apart need to be used to the fullest extent, and other diversified tools to evaluate mathematical capabilities that include mathematical creativity need to be further studied and developed. Qualitative studies on affective development of the gifted students and their creative problem-solving processes need to be conducted.

• Journal of Soil and Groundwater Environment
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• v.18 no.3
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• pp.33-51
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• 2013

Spatial and temporal characteristics of nitrate contamination and hydrogeochemical parameters were investigated for springs and surficial and bedrock groundwaters in northeastern part of Hongseong. Two field investigations were conducted at dry and wet seasons in 2011 for 120 sites including measurement of field parameters with chemical analyses of major dissolved constituents. Nitrate concentrations were at background levels in springs while 45% of bedrock groundwater and 49% of surficial groundwater exceeded the drinking water standard of nitrate (10 mg/L as $NO_3$-N). The difference in nitrate concentrations between surficial and bedrock groundwater was statistically insignificant. Cumulative frequency distribution of nitrate concentrations revealed two inflection points of 2 and 16 mg/L as $NO_3$-N. Correlation analysis of hydrogeochemical parameters showed that nitrate had higher correlations with Sr, Mg, Cl, Na, and Ca, in surficial groundwater in both dry and wet season. In contrast, nitrate had much weaker correlations with other hydrogeochemical parameters in bedrock groundwater compared to surficial groundwater and had significant correlations only in wet season. Temporally, nitrate and chloride concentrations decreased and dissolved oxygen (DO) increased from dry season to wet season, which indicates that increased recharge during the wet season affected groundwater quality. Aerobic conditions were predominant for both surficial and bedrock groundwater indicating low natural attenuation potential of nitrate in the aquifers of the study area.

• Anxiety and mood
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• v.2 no.1
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• pp.22-27
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• 2006

Objectives : There is a paucity of data on the long-term course of obsessive-compulsive disorder (OCD) and chronological relationship between OC symptoms and their related symptoms such as anxiety and depression. The purpose of this study was to investigate the longitudinal course of OC symptoms as well as anxiety and depression which are believed to be associated with OC symptoms. Methods : Data for 155 patients with OCD who completed general evaluation for OCD were used. Forty four were excluded to minimize the effect of the different age of onset on the clinical course. One hundred eleven patients finally participated in the analysis. Cross-sectional correlations between each symptom as well as between such symptoms and the duration of illness were analyzed. Further correlation analysis was done within two groups that were divided by 7 years of the duration of illness. Results : There were significant correlations not only between the severity of OC symptoms and anxiety but also between anxiety and depressive symptom, regardless of the duration of illness. These correlations between such symptoms were also found within patients with the duration of illness below 7 years, whereas these were not within the group with the duration of illness above 8 years. Conclusion : Patients with OCD in this study shows the moderate to severe level of OC symptoms irrespective of the duration of illness. Our finding also suggests that the OC symptoms, especially obsessions are closely related to anxiety and depressive symptoms and these relationships might be pronounced in relatively early phase of the OCD after onset.

• ALGAE
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• v.30 no.2
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• pp.139-146
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• 2015

Urchin barrens have been a major issue of rocky coastal ecosystems in temperate regions. In South Korea, the east coast and Jeju Island have especially been a focus because the area of barren ground increases in spite of continual efforts to install artificial reefs. This study approached the urchin barrens issue in South Korea, by focusing on a correlational analysis of urchin and macroalgal abundance. Urchin density and algal species coverage were obtained using a quadrat image analysis. Subtidal sites were then classified into three groups according to the average densities of urchins to evaluate the characterization of the macroalgal community: no urchin (NU) zone; transition (TR) zone, $4inds.\;m^{-2};$ and urchin (UR) zone, ${\geq}8inds.\;m^{-2}$. The average urchin density in the study site was $4.7inds.\;m^{-2}$ and 57 macroalgal species were found in the study site. From the NU zone to UR zone, total species number, species diversity index and evenness gradually decreased, whereas the dominance index increased. The algae species with negative correlations were Grateloupia divaricata, Polysiphonia morrowii, Chondracanthus intermedius, Delesseria violacea, Desmarestia viridis; and those with positive correlations were the crustose corallines, Sargassum horneri. Other species were not significantly correlated with urchin density. The significant correlations indicate that the abundance of some macroalgal species is proportionally regulated by sea urchin density. This study also shows how macroalgal vegetation changes in response to an urchin's density gradient in a natural condition; and there is a TR zone that existed with respect to an intermediate level of algal abundance.

• Journal of Environmental Impact Assessment
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• v.21 no.6
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• pp.917-925
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• 2012

In this study, we report the runoff characteristics of pollutants for Tamjin A and B watershed in Tamjin river basin using statistical analysis, such as correlation analysis and regression equation. Flow rate and water qualtiy data collected from 2 sampling sites(Tamjin A and B watershed) during 3 years(2009~2011) were analyzed for biochemical oxygen demand(BOD), total nitorgen(TN), total phosphorus(TP) and suspended solid(SS). The results showed that strong correlations were observed between flow rate and SS in Tamjin A, while weak correlations were observed among the BOD, TN, and TP. In Tamjin B, strong correlations were observed among the flow rate, SS and T-P except BOD and TP. Meanwhile, the values of $R^2$ for regression equations between flow rate and pollutants load were greater than 0.7. Results of these statistics indicated that there was a good agreement between flow rate and pollutants load. Also, the flow rate exponents of regression equations for BOD, TN, and TP were smaller than 1 in Tamjin A. In Tamjin B, flow rate exponents of regression equation for BOD and TP were smaller than 1. These results indicated that concentrations of BOD, TN, TP in Tamjin A and concentrations of BOD and TP were decreased as the flow rate was increased. This means that rater than nonpoint sources, point sources affect BOD, TN and TP in Tamjin A and BOD and TP in Tamjin B.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.3
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• pp.432-438
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• 2002

In order to design and analyze the performance of an axial-flow pump it is necessary to know the flow deviation, deflection angle and pressure loss coefficient as a function of the angle of incidence for the hydrofoil section in use. Because such functions are unique to the particular section, however, general correlation formulae are not available for the multitude of hydrofoil profiles, and such functions must be generated by either experiment or numerical simulation for the given or selected hydrofoil section. The purpose of present study is to generate design correlations for hydrofoils with double circular arc (DCA) camber by numerical analysis using a commercial code, FLUENT. The cascade configuration is determined by a combination of the inlet blade angle, blade thickness, camber angle, and cascade solidity, and a total of 90 cascade configurations are analyzed in this study. The inlet Reynolds number based on the chord and the inlet absolute velocity is fixed at 5${\times}$10$\^$5/. Design correlations are formulated, based on the data at the incidence angle of minimum total pressure loss. The correlations obtained in this way show good agreement with the experiment data collected at NASA with DCA hydrofoils.

• Ocean and Polar Research
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• v.24 no.3
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• pp.267-278
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• 2002

This study investigated the spatial characteristics of warming trends and the dipole-like pattern of temperature field in the Antarctic Peninsula using surface air temperature (SAT) of 10 stations in the vicinity of the Antarctic Peninsula. SAT data for the 1962-2001 period at 6 stations (Rothera, Faraday/Vernadsky, Bellingshausen, Orcadas, Esperanza, Halley) revealed in general the larger warming trends in autumn and winter except for Halley. The largest warming was shown for August in the west side of the Peninsula (more than $0.9^{\circ}C/decade$). On the other hand, the recent 14-year SAT data showed the strong warming trends at 9 stations except for Halley in the earlier period (April-June) than August for the 1962-2001 period. The largest warming appeared in May at Esperanza and Butler Island. SAT of the two sides showed significant positive correlations over most of the period except for the mid- and the late 1970s, in which significant negative correlations were found. In the correlation analysis between SAT and sea surface temperature (SST) anomalies in the NINO 3.4 region, strong negative correlation was found in the west side of the Peninsula. Details of the correlation analysis exhibited that the negative correlation was significantly strong from the early 1980s to the mid-1990s. However, it was difficult to find significant correlations of ENSO with SAT in the east side of the Peninsula. So, in this study it failed to find out clearly the out-of-phase relationship of SAT across the Antarctic Peninsula.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.12
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• pp.1311-1320
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• 2003

This paper proposed the estimating method of electromagnetic dosimetric reliability at in-vivo and in-vitro experiments. For more accurate consequences of these researches, we have tried to find out any correlations among output power, power density and specific absorption rate(SAR) with the results of in-vivo, in-vitro tests and SAR reports of cellular phone and PDA. In the case of in-vivo tests, the power density has close statistical correlations with SAR value and in the event of in-vitro tests, the output power has considerable statistical correlations with SAR containing duty factor. We analysed the coefficient of determination to estimate the dosimeoic uncertainty. If we use this method before evaluating techniques of measurement and analysis at both in-vivo and in-vitro experiments, we will conduct more accurate reliability test.

• The Journal of the Korea Contents Association
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• v.12 no.11
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• pp.539-548
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• 2012

This study investigated the effects of childcare teachers' role conflict and self leadership on psychological welfare. 64 day care centers located in Seoul and Gyeonggi-do were selected as its subjects and correlations and multiple regression analysis were conducted for 260 childcare teachers from the day care centers. The results of this study were as below. First, in terms of the relationships between childcare teachers' role conflict, self-leadership and psychological welfare, it has been shown that correlations of role stress, role ambiguity, action orientedness, constructive thought, and positive welfare were found in all sub-areas except for the sub-variables of natural reward and negative welfare, whereas correlations of role ambiguity, action orientedness, positive welfare were found also in all sub-areas except for the same sub-variables above. Second, after conducting multiple regression analysis, it has been noted that the variables that affected psychological welfare the most were natural reward followed by role ambiguity and role stress, whereas no statistical significance was found in all other sub-variables.