• Journal of The Korean Association For Science Education
• /
• v.36 no.4
• /
• pp.629-641
• /
• 2016

Understanding of how teachers change instruction can help predict what kind of educational materials is supportive or appropriate. On the basis of this idea, we explored elementary teachers' PCK progression on specific topics of astronomy: planet size and distance in solar system. To identify the development of PCK over time, we utilized learning progression (LP) as a conceptual framework. The progression of teacher PCK can also be illustrated as the hypothetical pathway from novice to expert like LP. Eight 5th grade elementary teachers participated in this study. We observed participating teachers' astronomy classes with the same topic. In order to document topic-specific PCK of participating teachers, we developed an analytic protocol consisting of four categories: knowledge of curriculum, knowledge of teaching strategies, knowledge of assessment, and astronomical thinking practice. In addition, we monitored the changes in the four participating teachers' PCK for two years in order to validate the evidences of the PCK progression. Participating teachers in this study took some intervention by attending a four-week pre-meeting with the researchers to profile an adaptive instruction. Through this research, we profiled four and five different levels of PCK progressions in three knowledge components (curriculum, teaching strategies, student assessment) and one astronomical thinking practice (systems thinking), respectively. Participating teachers demonstrated various levels and pathways in each component of PCK. This study released the empirical evidences in fostering instructional scaffolding, which is appropriate to the level of PCK of science teachers on specific topic.

• Food Science and Preservation
• /
• v.13 no.6
• /
• pp.796-802
• /
• 2006

In order to investigate the anti-inflammatory and cellular protective effects of Atractomorpha lata Motschulsky, Oxya japonica japonica Thunberg and Stethophyma magister Rehn, we first examined hydrogen peroxide-induced cytotoxicity in SH-SY5Y cells as well as antioxidant assays including DPPH and FRAP assays. We found that water, ethanol and methanol extracts of Oxya japonica japonica Thunberg and Stethophyma magister Rehn had potentials to anti-oxidant activity and especially water extract of Oxya japonica japonica Thunberg exhibited the most potent protective effects against $H-2O_2$-induced cytotoxicity in SH-SY5Y cells by MTT assay. Taken Together, these findings indicate that water extract of Oxya japonica japonica Thunberg could be useful insect resources for agrobiotechnological or oriental medicinal purposes.

• Journal of dental hygiene science
• /
• v.7 no.3
• /
• pp.167-177
• /
• 2007

The purpose of this study was to obtain basic data for dental implants prosthetic maintenance care after analysis perceptions of dental implants. A question was used to questionnaire by 210 dental patients at five dental clinics in the Jinju-city. In conclusion, 1. The knowledge level about implant is 'Never'(35.7%). 2. A feeling of unrest during implant surgery is 'pain'(37.6%). 3. The expectation level about dental implants function is 70% of natural teeth(36.2%). 4. The main function of implant teeth is 'mastication'(70.5%). 5. The implant hygiene supplies for the dental implants maintenance is 'proximal brush'(60%). 6. The important maintenance attitude for the dental implants is 'regularly dental examination'(42.9%). 7. The interval regularly for implant examination is 'six monthly'(44.8%).

• Education of Primary School Mathematics
• /
• v.20 no.1
• /
• pp.37-52
• /
• 2017

The purpose of this thesis is to analyze the current status of a program for an elementary math class for gifted students in Daegu and to propose a remedy. The main results of this thesis are as follows. First, goals of the gifted class and the basic operation direction were satisfactory, however plans for parent training programs and self evaluation of the classes were not presented. Therefore, it needs when and how to do for specific plan of gifted class evaluation and parent training programs. Second, The annual instruction plan has been restricted to the subject matter education and field trips and has not included specific teaching methods in accordance with the contents of learning program. The management of gifted classes, therefore, requires not only the subject matter education and field trips but also output presentations, leadership programs, voluntary activities, events and camps which promote the integral development of gifted students. Third, there is no duplication of content to another grade, and various activities did not cover the whole scope of math topics(eg. number and operation, geometry, measurement, pattern) equally. In accordance with elementary mathematics characteristics, teachers should equally distribute time in whole range of mathematics while they teach students in the class because it is critical to discover gifted students throughout the whole curriculum of elementary mathematics. Fourth, as there are insufficient support and operational lack of material development, several types of programs are not utilized and balanced. It is necessary for teachers to try to find the type of teaching methods in accordance with the circumstances and content, so that students can experience several types of programs. If through this study, we can improve the development, management and quality of gifted math programs, it would further the development of gifted education.

• Fire Science and Engineering
• /
• v.33 no.4
• /
• pp.140-151
• /
• 2019

It is to assess the indoor air quality of the chemical hazardous materials exposed to the fire after firefighters returned to the fire scene. The research subject randomly selected four fire stations located in Seoul, Korea. Two fire stations were set up as control groups after the return of the firefighting activities at the actual fire scene, and two other fire stations were set up as control groups to measure the air quality of the room at normal levels regardless of the action. We conducted 24-hour monitoring for all fire accidents that occurred in Seoul Metropolitan using fire safety map computer system. Also, indoor air quality was measured immediately after homecoming if the experiment group was to be dispatched due to an accident of intermediate or larger scale. 11 hazardous substance items such as fine dust, formaldehyde, volatile organic compounds, PAH, VCM, acidity, asbestos, CO₂, NO₂, O₃ were measured according to the process test method. Three of 11 types of harmful substances exceeded domestic and foreign standards, and one of them was found to be close to foreign standards. In particular, total volatile organic compounds, carbon dioxide and sulfuric acids were 2.5 times, 2.2 times and 1.1 times higher than the standard. Also, for formaldehyde and sulfuric acid, it was measured higher in the control group than in the case group. This findings could be used in policies to improve indoor air quality in the fire station of the Seoul Metropolitan Government.

• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.4
• /
• pp.435-443
• /
• 2014

Purpose: The purpose of this study was to analyze the design identity visual elements of optical shop brand$\underline{s}$ in order to provide objective data necessary for optical shop brands' design development. Methods: This study examined the design identity concept of the optical shop brands and analyzed visual elements of brand design identity with a focus on the symbols of domestic franchise optical shops, type of a symbol mark, representation style of logo type, color usage, use or non-use of character, etc. Results: Many symbols were directly associated with the eyeglasses, such as eyeglasses and eyes, face and iris. Along with that, letters or figures were also observed. For the type of symbol, most types were found to have the designs that took spherical and word mark shapes. Particularly, the word mark type had English words more often than Korean words. For logo types, the gothic format was dominant. In relation to the thickness of letter, thick boldface type was commonly used. The combination of 2 degrees was the color frequency used most often in the optical shop brand design. For the frequency of color usage, black and red colors were used most often. Particularly, the orange color, as well as the black color, was also often used for the main color of symbols or logo types. Meanwhile, the characters were used only in some optical shop. Most characters were animals and expressed in the cartoon and graphical forms. Conclusions: Typifier, symbol mark, logo type, color, and character are the elements forming the basic development system for brand design identity. Systematic design is needed which clearly ensures the function and role along with the mutual consistency as a important visual component of the optical shop brand.

• Journal of the Korean Applied Science and Technology
• /
• v.33 no.4
• /
• pp.802-812
• /
• 2016

Silicone foam is very useful as flame resistant material for many industrial areas such as high performance gasketing, thermal shielding, vibration mounts, and press pads. A silicone foam was prepared through simultaneous crosslinking and foaming by hydrogen condensation reaction of a vinyl-containing polysiloxane (V-silicone) and a hydroxyl-containing polysiloxane (OH-silicone) with hydride containing polysiloxane (H-silicone) in the presence of platinum catalyst and imorganic filler at room temperature. This is more convenient process for silicone foam manufacturing than the conventional separated crosslinking and foaming systems. Funtionalized silicones we used in this experiment were consisted with a V-silicone containing 1,0 meq/g of vinyl groups and a viscosity of 20 Pa-s, an OH-silicone with 0.4 meq/g of hydroxyl groups and a viscosity from 50 Pa-s, and an H-silicone containing 7.5 meq/g of hydride groups and a viscosity of 0.06 Pa.s. The effects of compositions of functionalized silicones and additives, such as catalyst and filler on the structure and mechanical properties of silicone foam were studied. 0.5 wt% of Pt catalyst was enough to accelerate the foaming rate of silicone resins. The addition of OH-silicone with lower viscosity accelerates the initial foaming rate and decreases the foam density, but the addition of V-silicone with lower viscosity reduces the tensile strength as well as the elongation. The final foam density, tensile strength, and elogation of silicone foam prepared under the SF-3 condition increase maximum to $0.58g/cm^3$, $3,51kg_f/cm^2$, and 176 %, repectively. We found out the filler alumina also played an important role to improve the mechanical properties of silicone foams in our foaming system.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.28 no.3
• /
• pp.123-129
• /
• 2018

Ink-jet printing technology with ceramic ink of the four digital primary colors (cyan, magenta, yellow, and black; CMYK) can provide stable coloration even in the high-temperature firing process. Ceramic ink-jet printing can be widely applied in construction and ceramic industries due to the advantages of accurate and fast printing process of digital images for various products. Generally, organic solvent with proper viscosity and surface tension has been used in digital ink-jet printing process. However, the needs of ceramic ink without VOCs emission is increasing. In the present study, eco-friendly ceramic ink was synthesized by combining alumino boro-silicate glass frit and $CoAl_2O_4$ inorganic pigment based on an aqueous solvent that does not generate VOCs. The rheological properties and dispersion stability of aqueous ceramic ink were optimized. Jetting behavior and printing characteristics of the ceramic ink were also investigated in detail. As a result, the formulated aqueous ceramic complex ink showed a suitable jetting behavior without satellite drop by adjusting viscosity and surface tension. The ceramic ink can be printed on glass substrate with minimized spreading phenomena duo to high contact angle.

• Journal of the Economic Geographical Society of Korea
• /
• v.3 no.2
• /
• pp.81-96
• /
• 2000

The study examines the present condition and prospects of venture firm accumulation center in the case of kwan-ak venture town. The survey shows most of companies have been founded since 1997. Their major items are software development and the average employees are under 10 workers. According to the questionary about the type of R&D and the level of innovation, technology innovation such as the development of new product is advanced whereas tacit innovation like inter-firm cooperation is very weak. And the source of idea and information is concentrated on the within-firms and research center As a result of the analysis of regional linkage, the dependence of production and R & D is large on kwan-ak-gu, but sales and information services have emphasis on Seoul area. In the light of the affiliation of inter-firm, they response sympathy with cooperation, but could not strengthen their commercial ties yet. At last, the policy for venture firm accumulation center must intend to make tacit measures through inventing of system instead of the simple means such as the assistance of location, finance and tax.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.7 no.1
• /
• pp.59-66
• /
• 2013

This study rehabilitation assistive technology system for people with disabilities employed by a company in the field of occupations and job satisfaction have adapted to, and for the rehabilitation assistive technology support(rehabilitation assistive technology hardware and the software) and service quality based on the quality of convenient for employees to work life by analyzing the factors that can act on adaptation employees on behavioral intentions was to determine the overall impact. Seoul, Gyeonggi, Incheon companies based in vocational education and training received in the employment of the disabled subject questionnaires were distributed, and finally 594 valid questionnaires were minor. In order to test the hypothesis SEM(structural equation model) were used, the results of this study can be summarized as follows. First, rehabilitation assistive technology hardware quality of the quality of rehabilitation assistive technology software affected. Second, rehabilitation assistive technology software quality on the quality of the service quality affected. Third, rehabilitation assistive technology hardware quality on the quality of the service quality affected. Fourth, quality of service, the quality of the adaptation of action for employees affected also. Fifth, rehabilitation assistive technology software for adaptive quality of the employees also had an impact on behavior. Sixth, rehabilitation assistive technology hardware to adapt the quality of the employees affected. And parameters (quality of service quality) influenced to as indirect effects. The results of this study support the rehabilitation assistive technology and rehabilitation assistive technology hardware and software) based, quality of service and quality of fused form acceptable to, the degree of action for employees to adapt more implications that may affect have provided.