• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.1
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• pp.39-46
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• 2011

This study was carried out to determine the forage yield, quality, and regrowth of Italian ryegrass (IRG) and barley sown on 2 March 2009 in Suwon. The five treatments were two IRG cultivars (Kowinearly with early maturity and Kowinmaster with medium maturity), one barley cultivar (Yuyeon), and two mixtures (Kowinearly + Yuyeon and Kowinmaster + Yuyeon). The first harvest date was 26 May, which was at late heading, heading and early dough stage of Kowinearly, Kowinmaster and barley, respectively. Regrowth yield was investigated on 29 June. The heading dates of Kowinearly and Kowinmaster were 16 May and 22 May, respectively, and that of barley was 13 May. The dry matter (DM) percentage were 13.0~18.4% at first harvest, and 22.5~24.8% at regrowth in all treatments. The forage yield of barley and Kowinmaster + Yuyeon mixture at first harvest was higher than that of IRG (p<0.05), but higher regrowth yield was observed in IRG, and then IRG + barley mixtures (p<0.05). The crude protein (CP) content and in vitro DM digestibility (IVDMD) of IRG at first harvest were 16.7~17.1% and 78.3~80.4%, respectively, which were higher than those of barley (CP 12.2% and IVDMD 72.6%) and IRG + barley mixtures. The total yields of DM, CP and digestible DM were high in Kowinmaster + Yuyeon mixture as 11,628 kg, 1,669 kg and 8,457 kg per ha, respectively. In conclusion, spring seeding of IRG + barley mixtures and/or barley were recommended when early harvest. Regrowth of IRG sown in early spring was vigorous. Mixture cultivation of IRG and barley was effective, because of forage yield and stable production, and harvest at June instead of May was desirable for forage productivity of spring sown IRG and barley.

• Journal of the Korean Home Economics Association
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• v.35 no.4
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• pp.111-124
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• 1997

The purpose of this study was to find out the effects of children's elementary school entrance age and sex on cognitive and social abilities. The subjects were 80 the same number was slected by elementary school entrance age(5-year and 6-year) and sex. Their cognitive and social abilities were measured by Intelligence Maturity Test and Revised Vineland Adaptive Behavior Scales. The data were statistically analyzed including descriptive statistics and multivariate analysis of variance. The results were as follows: 1) 6-year-old children had higher perceptive ability of sameness and calculation ability than 5-year-old children. Girls also had higher IQ and language concept than boys, 2) 6-year-old children's communication socialization and total social ability were higher than those of 5-year old children Girls' communication and total social ability were higher than those of boys. The implication was that it would be important to consider children's social ability if their entrance age were decided. In addition Early Entrance to Elementary School system should be reconsidered in the point of childer's developmental adaptation.

• Journal of the Korea Concrete Institute
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• v.16 no.5 s.83
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• pp.725-731
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• 2004

A field test program was conducted for the newly placed concrete pavement of US Interstate Highway 10 between March 26th and 28th, 2003. The test section was located between Van Horn and Sierra Blanca in Hudspeth County approximately 130 km east of El Paso, Texas. The main objective of the test was collecting moisture-related data to validate the models of effective curing thickness, evaporation rate, and moisture-based maturity. Effect of moisture loss on drying shrinkage strain was studied using additional test instrumentation.

• Journal of Families and Better Life
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• v.18 no.3 s.47
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• pp.71-84
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• 2000

The purpose of this study is to analyze the structure of maternal experiences. This study applies ethnographic case study, interview data were collected through in-depth interviews of 10 key interviewees. Findings were as follows: (1) Experiences of the body were about creating a new being through the pain of giving a birth and differed according to woman's self-evaluation of identity. (2) Child-rearing experiences marked a shift of position from a child to a parent. Interviewees experienced the hardhsip of life as a mother, its meanings differed according to the social context of interviewees. Child-rearing experiences meant a process of personal maturity. (3) Mother-child relationship shaped by child-rearing experiences, is a process of building meanings. It led to empathy and reinterpretation of her mother's life.

• Journal of the Korea Institute of Building Construction
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• v.2 no.2
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• pp.151-156
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• 2002

When fresh concrete is exposed to low temperature, the concrete may suffer frost damage due to freezing at early ages and strength development may be delayed. One of the solution methods for resolve these problems is to reduce freezing temperature of concrete by the use of chemical admixture called Accelerators for freezing resistance. In this study, we investigate the effect on strength development of cement mortar using accelerators for freezing resistance with the variance curing condition. As the result of this study, the mortar using accelerators for freezing resistance show that continuously strength development in curing condition of -5$^{\circ}C$. And compressive strength under the variance temperature condition was higher than constant temperature condition in same maturity.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.04a
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• pp.234-235
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• 2005

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.533-536
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• 2001

When fresh concrete is exposed to low temperature, the concrete may suffer frost damage due to freezing at early ages and strength development may be delayed. One of the solution methods for resolving these problems is to reduce freezing temperature of concrete by the use of chemical admixture called Accelerators for freezing resistance. In this study, we investigate the effect on strength development of cement mortar using accelerators for freezing resistance with the variance curing condition. As the result of this study, the mortar using accelerators for freezing resistance show that continuously strength development in curing condition of -5$^{\circ}C$. And compressive strength under the variance temperature condition was higher than fixed temperature condition in same maturity.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.274-279
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• 1995

The heat of hyderation of cement causes the internal temperature rise and volume change at early age, paticular in massive concrete structures. As the results of the temperature rise and extenal restraint conditions, the themal stress may induce cracks in concrete. Therefore various techenuques of the themal stress control of the mass concrete has been widely used. One of these techniques is pipe-cooling which is considered in this study. The objective of this paper is to develop finite element program which is capable of simulating the temperature history and the thermal stress considering pipe-cooling, creep and the modified elastic modulus dud to maturity effect.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.628-631
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• 2004

In this paper, mechanical properties of concrete incorporating CKD are discussed with W/B and fluidity. For setting properties, an increase in W/B retarded setting time greatly in $5^{\circ}C$, while accelerated in $20^{\circ}C$. For fluidity, an increase in slump delayed the setting time with dosage of SP agent. The presence of CKD has little influence on setting time compared with plain concrete. For compressive strength, an increase in maturity enhanced compressive strength. Fluidity had no relation to compressive strength. At low curing temperature, concrete with CKD has slight strength loss compared with plain concrete. However, remarkable strength loss at low curing temperature in early stage was not found, which can be applicable to low temperature environment concrete placing.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2001.10a
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• pp.233-236
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• 2001

This study explores on the static and dynamic growth patterns of high-tech ventures in Korea. We developed an integrative framework with target market (local vs. global), product/market maturity (existing vs. emerging), and technological capability (follower vs. pioneer). We also identified seven new ventures strategies as follows: i) reactive imitation, ii) proactive localization, iii) import substitution, iv) creative imitation, v) early market-entry, vi) global niche, and vii) global innovation. With five successful Korean new ventures, we found different competitive behaviors and performance among new venture strategic types. This study also observed two different growth patterns: growth through strategic replication and growth through strategic change. It depends on whether they are pursuing similar strategy over time or different strategy within for growth. In addition, we found that creative imitation plays a stepping-stone role in two-step internationalization processes. Although this study is exploratory and needs more empirical studies, it can provide new ventures with meaningful guidelines for growth and internationalization with a dynamic perspective.