• Korean Journal of Human Ecology
• /
• v.13 no.4
• /
• pp.485-496
• /
• 2004

The purpose of this study is to examine how the difference of parents' verbal control styles influence children's perspective-taking and interpersonal cognitive problem-solving skills. The subjects of this study were 117 five-year-old children with their parents included. The questionnaire used was relevant to the topic, such as parents' verbal control styles, young children's perspective-taking ability, and their interpersonal cognitive problem-solving skills. The percent, mean, standard deviation, three-way ANOVA, and Scheffe were used to analyze the data collected through SPSS WIN program. The major findings are as follows: First, a father's verbal control style makes a significant difference in young child's perspective-taking ability. However, there is no interaction effect between parents' verbal control styles and a child's sex. Second, a father's verbal control style makes a significant difference in young child's interpersonal cognitive problem-solving skills. Character-oriented verbal control mode of a father, in particular, produces more effects on boys than girls. Lastly, Two skills - alternative problem-solving skills and cause-solving skills - have interaction effects. Boys demonstrate higher skills than girls when parents apply character-oriented verbal control styles. Girls do so when mothers use position-oriented verbal control styles, especially in the area of cause-solving skills.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.13 no.5
• /
• pp.50-56
• /
• 2005

Aluminum member absorbs energy by stable plastic deformation under axial loading. While CFRP(Carbon Fiber Reinforced Plastics) member absorbs energy by unstable brittle failure but its specific strength and stiffness is higher than those of aluminum member. In this study, for complement of detects and synergy effect by combination with the advantages of each member, the axial collapse tests were performed for aluminum CFRP members which are composed of aluminum members wrapped with CFRP outside aluminum circular members. Based on the respective collapse characteristics of aluminum and CFRP members, crushing behavior and energy absorption characteristics were analyzed for aluminum CRRP members which have different CFRP fiber orientation angle and thickness Test results showed that aluminum CFRP members supplemented the unstable brittle failure of CFRP members due to ductile nature of inner aluminum members. It turned out that the CFRP fiber orientation angle and thickness influence energy absorption capability together with the collapse mode of the members.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.30 no.4 s.152
• /
• pp.519-530
• /
• 2006

The purpose of this study was to investigate whether management strategic types and entry strategy moderate the influence of Guanxi on the relationship performance between Korean apparel firms & Chinese partners. For these purposes, three hypotheses were developed and data was collected from 85 Korean apparel firms which have a business relationship with Chinese partners. Data was analyzed with SPSS methods such as frequency, factor analysis, multiple-regression, and hierarchical-regression analysis. The results were as follows: First, 'Prior to Guanxi' and 'Execution of Guanxi', which were sub-factors of Guanxi, influence positively on the relationship performance. And also the influence of 'Prior to Guanxi' was higher than 'Execution of Guanxi' on the relationship performance. Second, the influence of the 'Prior to Guanxi' on the relationship performance was stronger when Defender strategic type was used rather than other types. Third, the influence of the 'Prior to Guanxi' on the relationship performance was stronger when the entry scope of 'Both production & distribution in China' and the entry mode of 'Entry through Agent' were chosen.

• Journal of ILASS-Korea
• /
• v.22 no.4
• /
• pp.218-224
• /
• 2017

In order to improve the quality of air in urban areas, the emission regulations are being strengthened by the government. The on-road test of light-duty vehicles was started with PEMS because certification test mode does not sufficiently reflect on-road conditions. Therefore, The PEMS-based test was implemented from Sep. 2017 in Europe and Korea. However, this is lack of data on various on-road patterns in Korea. The purpose of the present study has analyzed the effect of speed per acceleration and acceleration on NOx emission on-road driving. The test route consisted of urban, rural, and motorway in Seoul. This study has been conducted by Euro-6 vehicles using on SCR system with PEMS. The on-road emission characteristics were evaluated by moving averaging windows (MAW) method. In results, RDE-NOx by severe driving pattern has been 1.4 times higher than soft driving pattern NIER Route 1.

• Bulletin of the Korean Chemical Society
• /
• v.29 no.3
• /
• pp.609-614
• /
• 2008

A periodic mesoporous organosilica material was synthesized by microwave heating (PMO-M) using 1,2-bis(trimethoxysilyl)ethane as a precursor in a cationic surfactant solution, and textural properties were compared with those of the product produced by conventional convection heating (PMO-C). These synthesized materials were characterized using XRD, TEM/SEM, N2 adsorption isotherm, 29Si and 13C NMR, and TGA, which confirmed their good structural orders and clear arrangements of uniform 3D-channels. Synthesis time was reduced from 21 h in PMO-C to 2-4 h in PMO-M. PMO-M was made of spherical particles of 1.5-2.2 m m size, whereas PMO-C was made of decaoctahedron-shaped particles of ca. 8.0 m m size. Effect of synthesis temperature, time, and heating mode on the PMO particle morphology was examined. The particle size of PMO-M could be controlled by changing the heating rate by adjusting microwave power level. PMO-M demonstrated improved separation of selected organic compounds compared to PMO-C in a reversed phase HPLC experiment. Ti-grafted PMO-M also resulted in higher conversion in liquid phase cyclohexene epoxidation than by Ti-PMO-C.

• Korean Journal of Materials Research
• /
• v.28 no.9
• /
• pp.516-521
• /
• 2018

Copper oxide thin films are deposited using an ultrasonic-assisted spray pyrolysis deposition (SPD) system. To investigate the effect of substrate temperature and incorporation of a chelating agent on the growth of copper oxide thin films, the structural and optical properites of the copper oxide thin films are analyzed by X-ray diffraction (XRD), field-emssion scanning electron microscopy (FE-SEM), and UV-Vis spectrophotometry. At a temperature of less than $350^{\circ}C$, three-dimensional structures consisting of cube-shaped $Cu_2O$ are formed, while spherical small particles of the CuO phase are formed at a temperature higher than $400^{\circ}C$ due to a Volmer-Weber growth mode on the silicon substrate. As a chelating agent was added to the source solutions, two-dimensional $Cu_2O$ thin films are preferentially deposited at a temperature less than $300^{\circ}C$, and the CuO thin film is formed even at a temperature less than $350^{\circ}C$. Therefore the structure and crystalline phase of the copper oxide is shown to be controllable.

• Macromolecular Research
• /
• v.15 no.2
• /
• pp.160-166
• /
• 2007

Novel multiblock copolymers, based on segmented sulfonated hydrophilic-hydrophobic blocks, were synthesized and investigated for their application as proton exchange membranes. A series of segmented sulfonated poly(arylene ether sulfone)-b-polyimide multiblock copolymers, with various block lengths, were synthesized via the coupling reaction between the terminal amine moieties on the hydrophilic blocks and naphthalene anhydride functionalized hydrophobic blocks. Successful imidization reactions required a mixed solvent system, comprised of NMP and m-cresol, in the presence of catalysts. Proton conductivity measurements revealed that the proton conductivity improved with increasing hydrophilic and hydrophobic block lengths. The morphological structure of the multiblock copolymers was investigated using tapping mode atomic force microscopy (TM-AFM). The AFM images of the copolymers demonstrated well-defined nanophase separated morphologies, with the changes in the block length having a pronounced effect on the phase separated morphologies of the system. The self diffusion coefficient of water, as measured by $^1H$ NMR, provided a better understanding of the transport process. Thus, the block copolymers showed higher values than Nafion, and comparable proton conductivities in liquid water, as well as under partially hydrated conditions at $80^{\circ}C$. The new materials are strong candidates for use in PEM systems.

• Journal of the Korean Chemical Society
• /
• v.20 no.4
• /
• pp.316-320
• /
• 1976

Based on the results of graft copolymerization to proteins, an attempt is made to derive the rate equations to explain the mechanism of Ce(IV) ion-initiated graft copolymerizations. In this system the oxidative termination by Ce(IV) $[R{\cdot}+ Ce(IV) ${\rightarrow}$ R(inert) + Ce(III) + H^+]$ is considered characteristic particularly in higher concentration of Ce(IV) ion. The change in the mode of termination reactions with change in Ce(IV) ion concentration makes possible the presence of an optimum Ce(IV) ion concentration for maximum graft copolymerization yield. This effect is reflected in presently derived equations.

• Journal of the Korea Institute of Building Construction
• /
• v.7 no.3
• /
• pp.115-122
• /
• 2007

As buildings become higher, larger, and more complex, safety issues for construction workers working at such environments become more important. We analyzed 83 critical accident cases reported to the KOSHA(Korea Occupational Safety & Health Agency) for construction cranes by types of cranes and by patterns of accidents and causes. There are more number of accidents related to mobile cranes than that related to tower cranes, but the numbers of dead were similar in both cases. The most dominant cause of crane accidents was "fall of materials". We also analyzed the cases of crane accidents using the FMEA(Failure Mode and Effect Analysis) in order to set up a priority for safety management and also to prioritize research and development items relating tower cranes. In the process, we tried to eliminate subjective indexes such as an expert group survey and use objective and quantitative indexes. As a result, it was found that critical crane accidents occurs most during the "lifting and translating" activity.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.18 no.6
• /
• pp.598-603
• /
• 2009

Resistance spot welding has been investigated to apply for manufacturing car bodies because of its high productivity. So quality of resistance spot weld is one of the major concerns for both automobile and aerospace industry. Current design trends in automotive manufacture have shifted emphasis to alternative lightweight materials in order to aid in producing vehicles with higher fuel efficiency and lower down the vehicle emission level for environmental control. There is increasing emphasis to provide lighter cars. Therefore there is an effort to use high strength steels such as HSLA, dual phase, in car body. However there is used in restricted because of difficulty in producing consistently high quality resistance spot welds. In this study, resistance spot welding schedules were developed to achieve acceptable welds with improved static mechanical properties. Improved resistance spot welding schedules were developed using post heating current to reduce the cooling rate, or in-process tempering to reduce the hardness of the weld produced. The effects of resistance spot welding process parameter on hardening fracture mode and static mechanical properties of the joints were determined.