• Korean journal of food and cookery science
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• v.23 no.1 s.97
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• pp.1-8
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• 2007

Extraction conditions were optimized using response surface methodology for preparing high-quality, hot water extracts from cultivated Chrysanthemum indicum L. petals. A fractional factorial design was applied to investigate the effects of added sample ratio ($X_1$), extraction temperature ($X_2$) and extraction time ($X_3$) variables on extract properties, such as, soluble solid contents ($Y_1$), sugar content ($Y_2$), ?E ($Y_3$), turbidity ($Y_4$), total phenol ($Y_5$) and DPPH ($Y_6$). Second-order models were employed to generate a 3-dimensional response surface for dependent variables and their coefficients of determination ($R^2$) ranged from 0.8408${\sim}$0.9914. The range of optimum conditions at $80^{\circ}C$ extraction for maximize characteristics of hot water extracts was 2.3${\sim}$2.7 g and 9.2${\sim}$11.2 hr.

• Journal of Hydrogen and New Energy
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• v.28 no.5
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• pp.570-576
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• 2017

Gas turbine system with steam injection has shown outstanding advantages such as high specific power and NOx reduction. In the present work, a comparative exergetic analysis was carried out for Steam Injected Gas Turbine (STIG), Regenerative Steam Injected Gas Turbine (RSTIG), and Regenerative After Fogging Gas Turbine (RAF). Effects of pressure ratio, steam injection ratio and steam injection method on the system performance was theoretically investigated. The results showed that the order of the highest exergy efficiency is RSTIG, RAF, and STIG for low pressure ratios but STIG, RSTIG, and RAF for high pressure ratios. In each arrangement, the combustion chamber has the highest exergy destruction and the compressor has the second one.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.161-162
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• 2018

Many researchers in South Korea have conducted regarding the safety climate and concluded that the safety climate effect on the safety performance. However, the survey tools that were used in domestic research were developed by individuals or designed by reconstituting, translating from previous studies. In addition, the safety climate as a low factor of organizational culture showed up in different types depending on business scale. In order to solve this issue, the objective of this study is to analyze the safety climate level of construction company depending on business scale in South Korea. first, the survey is conducted by NOSACQ-50 for construction workers. Second, it is analyzed how organizational culture affected the safety climate. Finally, the improvements are suggested on the level of safety climate. In the future, this study will be used as a baseline for the effects of the safety climate on the safety performance in construction site based on business scale.

• Journal of Family Resource Management and Policy Review
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• v.19 no.1
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• pp.49-71
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• 2015

The purpose of this study is to make suggestions for the ongoing process of an integration of the Healthy Families Center and the Center for Multicultural Families. Based on previous studies and interview data from nine service workers at the two institutions, we make the following suggestions. First, a systematic analysis tool should be developed in order to evaluate the effects of the integration initiative with reliability and validity. Second, empirical data should be collected from the users after the integration of the two institutions and be used to promote their satisfaction. Third, a specific preparation should be made to enhance the integration process of the service workers. Fourth, the integration should be considered in the context of the community and networks. Finally, further studies are needed to understand how the integration influence family policy and social policy in larger contexts.

• Human Ecology Research
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• v.53 no.5
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• pp.503-517
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• 2015

This study examined the relationships among children's perspectives on achievement-oriented parenting style, ego-resilience, school adjustment, and academic achievement. In order to analyze the associations, the study conducted a secondary analysis of the data found in the Korean Children and Youth Panel Survey (KCYPS) 2010-2011, which was a non-randomized controlled study designed with a longitudinal follow-up. We analyzed 1,212 students who were in the fourth and fifth grade at elementary school with Structural Equation Modeling (SEM). The results were as follows. First, higher achievement-oriented parenting style was associated with higher ego-resilience that contributed to higher academic achievement and higher school adjustment. Second, higher achievement-oriented parenting style was directly related to lower academic achievement and lower school adjustment. The findings support that children's ego-resilience is an important factor to improve school adjustment and academic achievement. In addition, the achievement-oriented parenting style is not helpful for their children's school outcomes (such as academic achievement and adjustment) even though parenting style improved their children's ego-resilience. Ego-resilience that is developed by achievement-oriented parenting style is likely to enhance children's school adjustment and academic achievement. The study presents policy and practice implications, limitations and areas for further research.

• Speech Sciences
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• v.4 no.2
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• pp.91-102
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• 1998

The present study attempted to modify the conventional Melodic Intonation Therapy (MIT) in three aspects: number of syllables of adjacent target utterances (ATU), melody patterns of ATU, and initial listening of melody and intoned speech with the eyes closed. The modified Melodic Intonation Therapy (MMIT) was applied to two severe Korean aphasics. The patients exhibited a severely nonfluent aphasia resulting from a left CVA(Cerebrovascular Accident). The purpose of the modification was to avoid perseveration and improve reflective listening skills. First, the treatment program avoided ATU with the same number of syllables. Second, four different patterns of melody were developed: rising type, falling type, V-type, and inverted V-type. One type of prosodic pattern was preceded and followed by another type of melody. These two variations were to decrease perseverative behaviors. Finally, the patients kept their eyes closed when the clinician played and hummed a target melody at the initial stage of the program in order to improve reflective listening skills. A single-subject alternating treatment design was used. The effects of MMIT were compared to the conventional MIT. Differing the number of syllables and the type of melodic patterns decreased perseverative behaviors and produced more correct names. The initial listening of the target melody with the patients' eyes closed seemed to increase their attentiveness and result in a more fluent production of target utterances. Probable reasons for the effectiveness of MMIT were discussed.

• KIEAE Journal
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• v.14 no.3
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• pp.55-63
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• 2014

This study selected and analyzed filter media that can be applied in non-point pollution reduction devices aimed at processing the source of pollution on site for road runoff that increases rapidly in rainfall-runoff in order to improve the water quality of urban areas. First, the factors that affect the quality of runoff caused by sources of non-point pollution include physical and social factors such as the usage of land around the area of water collection, type of pavement and movement of cars and people, as well as rainfall characteristics such as frequency, intensity, amount and duration of rainfall. Second, the purification tests of the filter media were processed for pH, BOD, COD and T-P, and the filter media showed to have initial purification effect at that items. However, the filter media showed to be very effective for the processing of SS, T-N, Zn and Cd from the beginning to the end. Third, for filter media, zeolite and vermiculite showed to be effective for processing SS, T-N, Zn and CD constantly, and composite filter media including zeolite showed to have strong processing effects. The authors conclude that this study can be applied to technical areas and policies aimed at reducing non-point pollution in urban areas and can also contribute to allowing eco-friendly management of rainfall as well as improvement of water quality.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.12S
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• pp.1200-1204
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• 2003

In this study, in order to develop the low temperature sintering ceramics for multi-layer piezoelectric transformer, PSN-PZT system ceramics were manufactured as a function of CuO addition and their dielectric and piezoelectric characteristics were Investigated. CuO addition facilitated densification at low temperature due to the effect of Cu$_2$O-PbO liquid phase. Through the X-ray diffraction pattern study, absence of second phase unwanted was confirmed. Among the specimen to which CuO was added, the 0.6wt% CuO added specimen sintered at 900$^{\circ}C$ and 920$^{\circ}C$ showed the most excellent mechanical quality factor and electromechanical coupling factor, respectively. Besides the densification accelerator, CuO acted as a accepter and increased mechanical quality. Compared with the specimen with no addition sintered at 1150$^{\circ}C$ , the 0.6wt% CuO added specimen sintered at 920$^{\circ}C$ showed the appropriate dielectric and piezoelectric characteristics for multi-layer piezoelectric transformer.

• Wind and Structures
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• v.7 no.2
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• pp.107-130
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• 2004

This paper presents a time-domain approach for analyzing nonlinear random vibrations of long-span suspended cables under transversal wind. A consistent continuous model of the cable, fully accounting for geometrical nonlinearities inherent in cable behavior, is adopted. The effects of spatial correlation are properly included by modeling wind velocity fluctuation as a random function of time and of a single spatial variable ranging over cable span, namely as a one-variate bi-dimensional (1V-2D) random field. Within the context of a Galerkin's discretization of the equations governing cable motion, a very efficient Monte Carlo-based technique for second-order analysis of the response is proposed. This procedure starts by generating sample functions of the generalized aerodynamic loads by using the spectral decomposition of the cross-power spectral density function of wind turbulence field. Relying on the physical meaning of both the spectral properties of wind velocity fluctuation and the mode shapes of the vibrating cable, the computational efficiency is greatly enhanced by applying a truncation procedure according to which just the first few significant loading and structural modal contributions are retained.

• Food Science and Preservation
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• v.6 no.3
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• pp.319-323
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• 1999

This study was conducted to minimize the deterioration of dried kiwifruit quality. Osmotic dehydration was carried out as pretreatment before drying. After the kiwifruits were pretreated under optimized osmotic dehydration conditions, they were dried by three drying methods(hot air drying, vacuum drying, freeze drying). Hot air drying and vacuum drying were superior to freeze drying in the drying speed. But vacuum and freeze drying preserved more vitamin C than hot air drying. Also, osmotic dehydrated kiwifruit kept better quality than nontreated kiwifruit. Diffusion coefficient which describes moisture transfer, was high in drying process pretreated with osmosis. The changes of vitamin-C followed the second-order reaction rate equation with high RE, respectively.