• Archives of design research
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• v.15 no.1
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• pp.143-152
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• 2002

As the Internet has been a daily instrument of our lives, the numbers of Internet users are increasing rapidly. Especially, we have to pay special attention to about rapid increasing of juvenile users. In the 1990's, Kids are growing up literally surrounded by new technologies and mu1timedia experiences. For these kids, most of the techno1ologies that we adults find surprising or even incredible are a part of their everyday landscape, a fact of life. Currently, only few of research and discussion has gone into understanding this field. And most of these web sites, set importance on furnishing information only. So educational characters of web are not manifested fully as well as children soon get board with learning with Internet so that feel difficulties in searching and accepting information. At this point, we must try to develop educational sites Not only to show information but also to offer a rich and entertaining time for kids while providing playful teaming and increased technological fluency. Fer this purpose, Web site should be all about combining play with learning. Site navigation should be easy and the pages load quickly. The page download time is also being considerable, which could send kids withy mouse-fingers looking for entertainment elsewhere. Everything about the site must have a familiar feel, uses adequate colors to be satisfied with the juveniles. Multimedia can help the communications in the websites. To maximize the educational effect, technological research and continues invest are need, in addition to usability test.

• The Journal of Engineering Geology
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• v.15 no.1
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• pp.9-17
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• 2005

A set of soil samples were picked up from a failed slope formed by rainfall in limestone zone in Jangseong-gun, Jeonnam, Korea, to find out its physical and mechanical characteristics for this study, and variation of safety factor depending on slope inclination was defined by analysing slope stability affected by rainfall. Decomposed limestone soil in the research area is composed of quartz, orthoclase, gibbsite, geothite, etc., with specific gravity of 2.73, and this soil is included in SC by unified soil classification system. Calcium ingredient decreased remarkably during weathering at its mother rock. Coefficient of permeability is 2.56×10/sup -4/ cm/ sec, similar to its value of silty clay. Cohesion decreases remarkably from 3.0 t/ ㎡ to 0.72 t/ ㎡, and Φ value of internal friction angle tends to decrease as it turns to be saturated soil from partial saturated soil in the shear test. To analyze slope stability affected by rainfall, it is reasonable to seek seepage depth with reference to rainfall＊ intensity. In the slope stability analysis, when the seepage depth is the larger, its safety factor is the less, which makes the slope unstable. Comparing with minimum safety factor, 1.5 of cut slope in consideration of the seep-age line, safety factor is found to be satisfactory only when inclination of cut slope of decomposed limestone soil is more than 1：1.2 slope at least considering rainfall. It is also found that decrease of cohesion has great effect on decline of safety factor of slope while partial saturated soil turns to be saturated soil.

• Food Science of Animal Resources
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• v.23 no.2
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• pp.103-108
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• 2003

The effect of fat content, thickness, and storage temperature and period of fresh meat samples on the migration of di-(2-ethylhexyl) adipate(DEHA) from plasticized PVC film was investigated. Pork samples were prepared to have different fat contents by mixing with pork loin and pork backfat and stored at 5$^{\circ}C$ for 2 d. The migration values of DEHA into the pork samples were increased with a high fat content. There was a gradual increase in the DEHA concentration as a function of prolonged exposure period and elevated storage temperature when the pork samples were stored at -2, 5 and l0$^{\circ}C$ for up to 7 d, respectively. The migration of DEHA into fresh pork and beef was limited only to a small depth under the meat surface($\leq$2 cm). The migration value was higher when the pork belly was wrapped double with plasticized PVC film compared to once after storage at 5$^{\circ}C$ for 3 d. However, when the samples was minced and repacked with new film after 2 d, and kept for a further 1 d, these showed lower migration value compared to the above two intact samples. Migration values exceeded in most cases the upper limit for DEHA migration proposed by the EU(18 mg/kg or 3 mg/d㎡), even though no limitation is currently set in Korea.

• Korean journal of communication and information
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• v.33
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• pp.169-191
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• 2006

Changing our monopoly broadcasting advertising system into free competition system may give rise to serious troubles that intensify commercialism of broadcasting and reduce diversity of public opinion. In the boundaries of public interest out of danger, korean broadcasting system should adopt a system that partially adopts the principle of free market. Broadcasting advertising sale system affect the whole broadcasting system because it functions as an effective capital-resource provider. Thus, it affects the broadcasting policies' righteousness and efficiency. Due to the non-elastic nature of the total advertising market, broadcasting advertising's size affects other media's capital allocation process. Therefore, broadcasting advertising sales system not only affects broadcast's social duty and public interest, but also affects the whole media industry. First, provide fair and open-competitive measures to support broadcast sales policy so that the market-based system can be run smoothly. Second, block any un-due influence from advertisers by separating production/programming and advertising sales. Third, sustain public broadcast system, not based on the advertising sales but based on the subscription fee. Fourth, social intervention of the advertising market. Fifth, provide policies that can set up multiple media channels/outlets and public opinion. By providing the minimum capital resources to the public broadcasting system, the broadcasting system can act on its public-interest duty and support the people's right-to-know rights.

• Korean Journal of Optics and Photonics
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• v.18 no.6
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• pp.432-440
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• 2007

Optical simulation methods such as a ray tracing technique have been widely used to predict the optical performances of collimating films for LCD backlight applications. It is necessary to optimize simulation conditions which have substantial effect on the simulation result in order to predict accurate performances of collimating films. We have set up a very simple backlight model consisting of a reflection film, a virtual flat light-source, and a prism film, which is a representative collimating film for backlight, in order to analyze the simulation conditions which are strongly correlated with the on-axis luminance gain and the viewing-angle characteristics of prism films. It was found that the dependence of the relative change in the on-axis luminance on the structure and material properties of collimating films can be derived from the above-mentioned simple BLU model and from simulation using it. However, the exact reflection property of the reflection film and the distribution of the incident light onto the optical film were found to be very important for revealing exact viewing-angle characteristics of collimating films.

• Journal of the Korean Dietetic Association
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• v.12 no.2
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• pp.105-117
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• 2006

The purpose of this study was to investigate the needs of educators, learners and parents in elementary schools for implementing a systematic nutrition education program by nutrition teachers to begin in 2006. The subjects were 833 dietitians, 808 principals, 3,141 teachers, 7,577 students and 6,003 parents in elementary schools. A fairly large proportion of the principals (98.4%), teachers (95.5%), parents (96.6%) and students (62.8%) responded that nutrition education is urgently needed. Every dietitian, principal and teacher has recognized that for the enforcement of a nutrition program in the future, the placement of one nutrition teacher in every school is needed without a moment's delay. Many subjects responded that elementary low grades are the most proper time for nutrition education for students and it is also needed to extend this not only to students, but also parents and teachers who have a direct influence on them. In the education hour, they responded that it is proper one hour a month for teachers and one hour a week for students. Fifty-six percent of dietitians, 58.3% of principals and 67.0% of teachers responded that the best educational way to heighten the effect of nutrition education was education through discretional activities. It was found that 46.4% of students have wanted nutrition education to be enforced during special activities. Education through their school homepage or in-school broadcasting system, while it has been most utilized, was low in a degree of preference with 10.9%. In regards to a nutrition program, principals and parents have attached much importance to the dining etiquette, dietary attitudes, and relations of foodstuffs with health, while dietitians and teachers have made much of a balanced eating habit, and the relations of dietary life with health. Finally, for a nutrition program to be enforced towards a direction that the educators and students want, it is judged that first of all the role of nutrition teachers is the most important, furthermore the support of manpower and the budget should be made.

• Journal of Digital Convergence
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• v.14 no.1
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• pp.99-119
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• 2016

Medium and Small Firms have faced complex and dynamic environments that have been attributed to increases in the globalization and competitiveness of the global economy. To success in this environments, Medium and Small Firms should set up management strategy and introduce strategic performance management system. And, the strategic performance management system are modified to fit in management strategy. The purpose of this study is to find out firstly, whether management strategy types affect the organizational performance and the intensity of the types makes a difference on the performance and secondly, whether the evaluation system or the degree of utilizing the system affects the organizational performance and finally, whether the interaction between management strategy types and strategic performance management system makes a significant influence on the organizational performance. In this paper, we categorize the type of strategy for Medium and Small Firms in Gyeongsangbuk-do and Daegu areas, and study whether Firm's performance can be improved by designing appropriate strategic performance management system.

• Journal of Welding and Joining
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• v.34 no.2
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• pp.1-10
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• 2016

The use of materials for modern lightweight auto-bodies is becoming more complex than hitherto assemblies. The high strength materials nowadays frequently used for more specific fields such as the front and rear sub frames, seat belts and seats are mounted to the assembled body structure using bolt joints. It is desirable to use nuts attached to the assembled sheets by projection welding to decrease the number of loose parts which improves the quality. In this study, nut projection welding was carried out between a nut of both boron steel and carbon steel and ultra-high strength hot-stamped steel sheets. Then, the joints were characterized by optical and scanning electron microscope. The mechanical properties of the joints were evaluated by microhardness measurements and pullout tests. An indigenously designed sample fixture set-up was used for the pull-out tests to induce a tensile load in the weld. The fractography analysis revealed the dominant interfacial fracture between boron steel nut weld which is related to the shrinkage cavity and small size fusion zone. A non-interfacial fracture was observed in carbon steel nut weld, the lower hardness of HAZ caused the initiation of failure and allowed the pull-out failure which have higher in tensile strengths and superior weldability. Hence, the fracture load and failure mode characteristics can be considered as an indication of the weldability of materials in nut projection welding.

• Fire Science and Engineering
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• v.24 no.4
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• pp.12-17
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• 2010

The purpose of this study is to determine how effectively waste tire recycled material mixed with flame retardant work in combating fire. As discovered in the previous study, waste tire mixed with cement mortar has more insulation capacity. However, this mortar is weak against fire. Therefore flame retardant, with a specific proportional mix, will be added to increase its fire prevention capacity. Tests will be made in accordance with ISO 5657 procedures for measuring fire ignition time, flame and shape variation of test pieces at the Building Material Test Institute. The test piece will be set up with horizontal levels having a constant radiation heat of $1{\sim}5W/cm^2$. Temperature transfers and increases from the surface into the interior. Combustible gases result due to pyrolysis, and regular contact is maintained between the fire source and the center of the test piece for assessment purposes. Ignition has not been occurred without adding retardant meaning that there is almost no possibility of ignition of waste tire particle. This fact can be considered as fire load to appreciate a volume of combustion materials. Flame is not occurred due to heat-absorbing effect by adding non-organic series retardant into waste tire particle. Conclusions have been summarized as follows; 1) Combustion of building material can be decreased by adding retardant to waste tire-mixing mortar. But compressive strength and insulation capacity of the material should be measured later. 2) Firing prevention and ignition are main points of building fire. Reasonable fire engineering assessment of interior material should be made for establishing effective disaster prevention system.

• Journal of Korea Technology Innovation Society
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• v.14 no.1
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• pp.22-39
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• 2011

This study examines the wage level from a viewpoint of major-job match as part of an analysis on the skill mismatch problem in 4-year college graduates. The empirical analysis explicitly incorporate the sample selection bias as an econometric problem not only suggested but merely introduced in the earlier studies. This study also set up a major-job match variable, which was usually handled as a binary variable for analytical convenience, as a polychotomous choice variable in selection equation as provided by the survey. In particular, it considered multi-cohort survey on graduates of the years 1982, 1992, and 2002 for the empirical analysis. As a result of empirical analysis, the wage premium of a major-job match was identified. This result was consistent after the consideration of a sample selection bias and also after modeling the major-job match variable as polychotomously selective. Through an analysis classified by the major, this study identified a relatively high wage premium among Social Science, Engineering, and Science majors. However, there was a difference in the effect of selection among these majors. Also, by assessing cohort effects this study found that the skill mismatch had rapidly progressed in 1992, while difference between 1992 and 2002 cohorts are insignificant. The analysis suggests that wage level is better understood within the context of both sample selection and major-job match, and regardless of model specification the major-job match affects wage strongly.