• East Asian mathematical journal
• /
• v.36 no.3
• /
• pp.377-387
• /
• 2020

In this paper, we provide detailed proof of the Sawyer type characterization of the two weight estimate for the dyadic paraproduct. Although the dyadic paraproduct is known to be a well localized operators and the testing conditions obtained from checking boundedness of the given localized operator on a collection of test functions are provided by many authors. The main purpose of this paper is to present the necessary and sufficient conditions on the weights to ensure boundedness of the dyadic paraproduct directly.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2002.08a
• /
• pp.355-358
• /
• 2002

The deformation behavior of the frame for tension mask CRT is investigated by experiments and finite element method. We calculate and measure the stress-strain relation at the stress concentrations. The endurance test at 100$^{\circ}C$ was performed for checking tension decrease with time.

• The Journal of the Korean dental association
• /
• v.22 no.4 s.179
• /
• pp.329-332
• /
• 1984

The author observed a patient of ectodermal dysplasia with oligodontia. The treatments were done as follows: Vital pulpotomy and restorative treatment were done as usual method. Removable type space maintainer was set on the area of primary teeth removed. Follow-up checking were required for the observation of growth and development of the permanent teeth and the jaw.

• Textile Coloration and Finishing
• /
• v.26 no.4
• /
• pp.331-338
• /
• 2014

In this research, split-type complex yarn of 20:80, 40:60, 50:50 nylon6/polyester composition ratio was used in order to impose unique sense on split-type complex woven. After treating both split-type complex yarn of each ratio and its produced woven in alkali solution, we got the following results by checking physical properties based on alkali proportion and treatment time. Under the condition of NaOH 20% in this experiment, it took approximately double time 20% loss of weight. The loss of weight became high when polyester proportion of N/P(nylon6/polyester) composition ratio was low, in the same fineness yarn. Even though polyester proportion was low, the loss of weight was low when the fineness was high. N/P division was well processed at about 25% loss of weight under the condition of NaOH 20%, treatment temperature $50^{\circ}C$, and treatment time 60 minutes. The research provides that the loss of weight should be processed around treatment time 24 hours in the case of NaOH concentration 15%, and treatment time 15 hours in the case of NaOH concentration 18%, respectively, in order to achieve N/P woven division ratio of about 70%-80% in industrial fields.

• Journal of the Korean Institute of Gas
• /
• v.5 no.4 s.16
• /
• pp.85-91
• /
• 2001

This paper presents safety analysis of LNG leakage in a prestressed concrete outer tank, which is strongly related on the leak checking effects of the PC structure with and without a residual compression zone based on the BS 7777 codes. The full containment type outer tank which is constructed by a prestressed concrete may be destroyed by leaked cryogenic fluids. The FE calculated results show that the total leak checking time of the PC structure with $10\%$ residual compression zone is about 9 days for $-162^{\circ}C$ liquids. But, three primary pumps in an inner tank may operate to send cryogenic fluids for 6 days, which are stored in an inner tank of $140,000m^3$ capacity This means that the prestressed concrete outer tank may be safe for $-162^{\circ}C$ cryogenic fluids leaked from the demolished inner tank.

• Corrosion Science and Technology
• /
• v.6 no.3
• /
• pp.128-132
• /
• 2007

For a quantitative inspection on the performance of weathering steel bridges, we have investigated the relationship between the corrosion rate and the composition of the rust layers formed on weathering steel bridges located in various environments in Japan and applied a protective ability index (PAI) to the bridges. The corrosion rates were clearly classified by the PAI, ${\alpha}/{\gamma}*$ and sub index of $({\beta}+s)/{\gamma}*$, where $\alpha$, \gamma*, $\beta$ and s are the mass ratio of crystalline $\alpha-FeOOH$, the total of $\gamma$-FeOOH+ $\beta$-FeOOH + the spinel-type iron oxide (mainly $Fe_3O_4$), $\beta-FeOOH$ and spinel-type iron oxide, analyzed by powder X-ray diffraction, respectively. In the case of ${\alpha}/{\gamma}$*>1, the rust layer works protective enough to reduce the corrosion rate less than 0.01 mm/y. The sub index $({\beta}+s)/{\gamma}*$<0.5 or >0.5 classifies the corrosion rate of the non-protective rust layers, therefore the former state of the rust layer terms inactive and the latter terms active. The quantitative inspection of a weathering steel bridge requires a performance-inspection (PI) and periodical deteriorationinspections (DI). The PI can be completed by checking of the PAI, ${\alpha}/{\gamma}*$. The DI on the weathering steel bridges where deicing salt is sprinkled can be performed by checking the PAI, $({\beta}+s)/{\gamma}*$.

• Journal of the Korea Convergence Society
• /
• v.11 no.5
• /
• pp.335-340
• /
• 2020

In this study we conducted a questionnaire survey by purposive quota sampling(n=566) by status of workers(permanent workers, temporary workers and business owners) and age group(20-59 years old) for single households engaged in economic activities in order to compare the health behaviors and health checking by employment type and age. By employment type, the sleep time of permanent workers was significantly less than that of other groups(p<0.001), and the rates of health and oral examinations in permanent workers were significantly higher(p<0.001). By age group, as the age increased, the oral condition was worse(p<0.001), but the rates of not taking oral examinations were significantly higher(p=0.023). This study can be meaningful as basic data for making a healthy living environment according to various characteristics of single households.

• The Mathematical Education
• /
• v.60 no.2
• /
• pp.229-247
• /
• 2021

Students' mathematical thinking is represented via various forms of outcomes, such as written response and verbal expression, and teachers could infer and respond to their mathematical thinking by using them. This study analyzed 39 elementary teachers' competency to notice students' problem-solving strategies containing mathematical errors in fraction addition and subtraction with uncommon denominators problems. Participants were provided three types of students' problem-solving strategies with regard to fraction addition and subtraction problems and asked to identify and interpret students' mathematical understanding and errors represented in their artifacts. Moreover, participants were asked to design additional questions and problems to correct students' mathematical errors. The findings revealed that first, teachers' noticing competency was the highest on identifying, followed by interpreting and responding. Second, responding could be categorized according to the teachers' intentions and the types of problem, and it tended to focus on certain types of responding. For example, in giving questions responding type, checking the hypothesized error took the largest proportion, followed by checking the student's prior knowledge. Moreover, in posing problems responding type, posing problems related to student's prior knowledge with simple computation took the largest proportion. Based on these findings, we suggested implications for the teacher noticing research on students' artifacts.

• Archives of Plastic Surgery
• /
• v.33 no.5
• /
• pp.577-580
• /
• 2006

Purpose: Hemangioma of the breast is an infrequent finding and usually encountered incidentally when checking for other disease. Most of hemangiomas of the breast are asymptomatic, not palpable perilobular type. Cavernous hemangioma of the breast is rare and only a few reports about this type of lesion are present. No example has been reported about reconstruction of the breast after resection of large cavernous hemangioma. Methods: We report here a case of immediate breast reconstruction using a Becker implant after subcutaneous mastectomy for a large cavernous hemangioma involving almost entire breast. Results: Symmetry is well maintained after 3 years without deformity or recurrence. Conclusion: The clinical prognosis of breast cavernous hemangioma is good after total excision and reconstruction.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.03a
• /
• pp.871-876
• /
• 2010

When surface Concrete Face Rock fill Dam constructs than existent center core type rock fill dam, it is much prevalent form in domestic these day by quality control of that is profitable and weather condition etc. of coreZone. C.F.R.D is less research about seismic survey(Refractional Seismic Prospectin, Resistivity Prospecting) of levee body than fill dam. Thus as C.F.R.D seismic survey is less, safety of that consist is short most development flue is high reason. That is not checking target of minuteness safety diagnosis and so on by short operation period. Wish to analyze inquiry incidental and difference with center core type dam and acquire C.F.R.D preservation administration upper necessary inquiry condition forward hereafter.