• Title/Summary/Keyword: process grade

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Analyses of the Basic Inquiry Process in Korean 3-10 Grade Science Textbooks: Focused on Observation and Measurement (우리나라 3-10학년 과학 교과서에 나타난 기초탐구과정 분석: 관찰 및 측정 탐구요소를 중심으로)

  • Park, Bo-Hwa;Kim, Hee-Kyong;Lee, Bong-Woo
    • Journal of The Korean Association For Science Education
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    • v.27 no.5
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    • pp.421-431
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    • 2007
  • The purpose of this study was to examine the characteristics of observation and measurement inquiry process in the Korean science textbooks. For the inquiry process of observation, the higher grade textbooks contained more 'comparative observation' rather than 'simple observation'. Students should express their observation results in written words rather than verbal descriptions in the higher grade. For the inquiry process of measurement, the temperature measurement was the most frequent measurement activity. 'Measurement design' was found more frequently in the lower grade textbooks. The uses of measurement tools were not presented systematically and were presented restrictively when the relevant experiment wanted to use these tools. The higher grade textbooks include 'quantitative measurements' rather than 'qualitative measurements' and 'operation measurement' rather than 'simple measurement'. In the application of measurement results, we had difficulty in finding the activities related with the usage of unit, unit conversion, significant figure, error and uncertainty.

Preparation of High-grade Silica Sand for Metallurgical-grade Si Using a Physical Beneficiation (금속급 실리콘용 고순도 규사 제조를 위한 물리적 정제 특성)

  • Yang, Young-Cheol;Jeong, Soo-Bok;Chae, Young-Bae;Kim, Seong
    • Journal of the Mineralogical Society of Korea
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    • v.22 no.3
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    • pp.191-197
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    • 2009
  • It is very important to raise the purity of silica for manufacturing metallurgical-grade silicon because the purification of silicon in the smelting process is very difficult. In present study, the silica sand which is obtained from Vietnam was mineralogically analyzed. Based on the results, a novel process to separate impurities from the silica sand was developed, which consisted of classification, specific gravity and magnetic separation steps. Using the developed process, high-grade silica sand concentrate containing over 99.8 wt% $SiO_2$ was prepared, being suitable for manufacturing the metallurgical-grade silicon.

The Analysis of Educational Objectives by Observation in the 3rd and 5th Grade Science Instruction (관찰에 의한 국민학교 3, 5학년 자연과 수업의 목표 분석)

  • Ko, Se-Hwan;Kim, Hyo-Nam
    • Journal of The Korean Association For Science Education
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    • v.11 no.1
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    • pp.51-57
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    • 1991
  • This study pursued to find out the degree to which educational objectives are pursued in the 3rd and 5th grade science instructional of an elementary school. Twenty science instruional hours are observed during two month from May to July, 1989. Klopfer's science educational objectives system is used as the tool of objective analysis. Questionnaires for the ideal proportions of the educational objectives are answered by the professors and elementary school teachers. The writers regarded those results as the ideal proportions of the educational objectives. Results from the analysis of the instruction are as follows : 1. Results from analysis of the instruction in the third grade are as follows : knowledge and comprehension (A. 0) objectives are found to be pursued. about 40%. scientific inquiry process(B. 0-E. 0) objectives, about 29%, application of scientific knowledge and methods(F. 0) objectives. about 10%, manual skills(G. 0) objectives, about 11%, scientific attitudes and interests(H. 0) objectives, about 10% and orientation(I. 0) objectives is not pursued. 2. Results from analysis of the instruction in the fifth grade are as follows: knowledge and comprehension(A. 0) objectives are found to be pursued. about 31%, scientific inquiry process (B. 0-E. 0) objectives. about 38%, application of scientific knowledge and methods (F. 0) objectives, about 13%, manual skills(G. 0) objectives, about 7%, scientific attitudes and interests(H. 0) objectives, about 10%. 3. Results from the ideal proportions are as follows : Knowledge and comprehension(A. 0) objectives, 20.5%, scientific inquiry process(B. 0-E. 0) objectives, 46.5%, application of scientific knowledge and methods(F. 0) objectives. 8%, manual skills(G. 0) objectives. 9.5%, scientific attitudes and interests (H. 0) objectives, 9% and orientation(I. 0) objectives, 6.5%. 4. "You ideality index" is 29 in the third grade and 23 in the fifth grade. Science instruction of the fifth grade can be interpreted to be nearer to the ideal instruction in terms of educational objectives.

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The Dyeing Properties and Antibiosis of Fabrics Dyed with Agastache rugosa Extract (배초향 추출액을 이용한 염색포의 염색성 및 항균성)

  • Park, Young-Hee
    • Journal of Fashion Business
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    • v.16 no.1
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    • pp.16-25
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    • 2012
  • As the test results for surface color, dyeing durability, antibiosis of cotton fabrics and silk fabrics dyed with Agastache rugosa extract, the following conclusions were obtained. The surface color of all the dyed fabrics was confirmed mostly as a GY system. As the result of chrominance(${\Delta}E_{ab}$) measurement, in the case of cotton fabrics the dyed fabrics treated with $Al_2(SO_4)_3$ mordant showed the highest value and in the case of silk fabrics the non-mordant dyed fabrics showed the highest value. The dyeing durability of test fabrics dyed with Agastache rugosa extract are as follows. As the test results of colorfastness to laundry for cotton dyed fabrics, the discoloration degree showed 1st-2nd grade and the contamination degree showed 4th-5th grade. As the test result of colorfastness to dry cleaning for silk dyed fabrics, the contamination degree showed from 1st to 3rd-4th grade. As the test results of colorfastness to acid artificial perspiration, the discoloration degree showed from 1st to 3rd-4th grade and the contamination degree showed from 3rd to 4th-5th grade. As the test results of colorfastness to alkaline artificial perspiration, the discoloration degree showed from 1st to 4th grade and the contamination degree showed from 3rd to 4th-5th grade. The colorfastness to sunlight showed from 1st to 2nd grade. The colorfastness to rubbing showed from 3rd to 4th-5th grade in dry process and from 2nd-3rd to 4th-5th grade in wet process. As the test results of antibiosis, the decrease rate of germs to virus Klebsiella pneumoniae and Staphylococcus aureus showed at least more than 99% after the wash of 10 times. As the test results of antifungal activity to mycete Trichophyton mentagrophytes and Aspergillus niger, the both cotton and silk dyed fabrics didn't gain the significant antifungal effect.

Properties of Chemical Grade and Smelting Grade Aluminium Trihydroxide (화학제품용 및 금속제련용 수산화알루미늄 제품 특성)

  • Kim, Dae-Woong;Baik, Yong-Hyuck
    • Journal of the Korean Ceramic Society
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    • v.38 no.9
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    • pp.822-828
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    • 2001
  • Bayer process is based on the extraction of aluminium trihydroxide from bauxite. The process is operated with the several criteria such as primary crystal size, particle size distribution and yield etc.. In this study basing on the previous results, an investigation on the effect of chemical grade and smelting grade aluminium trihydroxide precipitation condition were undertaken. As a result, particle size was 42∼44${\mu}$m form chemical grade product and 74∼77${\mu}$m for smelting grade product. The yield and solubility by acid of chemical grade product was higher than smelting grade product. The attrition index of smelting grade product was lower than that of other commercial product because primary crystal size of the smelting grade product was small.

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A study on the changes of carcass muscle distribution in the high quality meat production of Hanwoo steers in Kyungnam (경남지역 거세한우의 고급육 생산을 위한 도체 근육부위별 분포도 차이에 대한 연구)

  • Kim, Cheol-Ho;Kim, Taeg-Seog;Kim, Chung-Hui
    • Korean Journal of Veterinary Service
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    • v.43 no.2
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    • pp.45-52
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    • 2020
  • A grading system is implemented to evaluate the meat quality of Hanwoo. In the grading system, grade 1++A is the highest grade. Livestock farms breed Hanwoo with good quality feed in order to obtain the highest grade. In this process, the content ratios of muscles in individual regions can be changed. To find out the muscle distribution ratios of Hanwoo steers, grade 1A, 1+A, and 1++A Hanwoo steers were compared with grade 1+A Hanwoo female. Grade 1A Hanwoo steers had higher ratios of shank (SK), brisket and flank (BF), neck chain (NC), and inside skirt (IS) meats and a lower ratio of striploin (SL) meat compared to grade 1+A Hanwoo feamle. Grade 1++A Hanwoo steers had higher ratios of neck (NK) and loin (LN) meats and lower ratios of inside skirt (IS), tenderloin (TL), top round (TR), eye round (ER), bottom round (BR), bottom sirloin triangle (BST), and knuckle (K) meats compared to grade 1+A Hanwoo steers. In comparison between grade 1A and 1++A Hanwoo steers, the ratio of shank (SK) was significantly lower in higher quality meats. If the changes are continuously studied to improve the process so that the ratios of partial meats of the regions highly preferred by consumers can increase, it will contribute to increases in the incomes of livestock farms and enable Hanwoo to grow into a global brand.

Developing Continuous Stabilization Process for Textile-Grade PAN Fiber-Based Carbon Fiber Using UV Irradiation (저가형 탄소섬유 개발을 위한 자외선 조사 기반 의류용 PAN 섬유의 연속식 안정화 공정 개발)

  • Moon, Joon Ha;Seong, Honggyu;Yoo, Jiseon;Cho, Se Youn;Choi, Jaewon
    • Journal of Powder Materials
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    • v.29 no.5
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    • pp.418-423
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    • 2022
  • Carbon fibers (CFs) are considered promising composite materials for various applications. However, the high cost of CFs (as much as $26 per kg) limits their practical use in the automobile and energy industries. In this study, we developed a continuous stabilization process for manufacturing low-cost CFs. We employed a textile-grade polyacrylonitrile (PAN) fiber as a low-cost precursor and UV irradiation technique to shorten the thermal stabilization time. We confirmed that UV irradiation on the textile-grade PAN fibers could lower the initial thermal stabilization temperature and also lead to a higher reaction. These resulted in a shorter overall stabilization time and enhancement of the tensile properties of textile-grade PAN-based CFs. Our study found that only 70 min of stabilization time with UV irradiation was required to prepare textile-grade PAN-based low-cost CFs with a tensile strength of 2.37 ± 0.22 GPa and tensile modulus of 249 ± 5 GPa.

Ammonium uranate hydrate wet reconversion process for the production of nuclear-grade UO2 powder from uranyl nitrate hexahydrate solution

  • Byungkuk Lee ;Seungchul Yang;Dongyong Kwak ;Hyunkwang Jo ;Youngwoo Lee;Youngmoon Bae ;Jayhyung Lee
    • Nuclear Engineering and Technology
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    • v.55 no.6
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    • pp.2206-2214
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    • 2023
  • The existing wet reconversion processes for the recovery of scraps generated in manufacturing of nuclear fuel are complex and require several unit operation steps. In this study, it is attempted to simplify the recovery process of high-quality fuel-grade UO2 powder. A novel wet reconversion process for uranyl nitrate hexahydrate solution is suggested by using a newly developed pulsed fluidized bed reactor, and the resultant chemical characteristics are evaluated for the intermediate ammonium uranate hydrate product and subsequently converted UO2 powder, as well as the compliance with nuclear fuel specifications and advantages over existing wet processes. The UO2 powder obtained by the suggested process improved fuel pellet properties compared to those derived from the existing wet conversion processes. Powder performance tests revealed that the produced UO2 powder satisfies all specifications required for fuel pellets, including the sintered density, increase in re-sintered density, and grain size. Therefore, the processes described herein can aid realizing a simplified manufacturing process for nuclear-grade UO2 powders that can be used for nuclear power generation.

Evidence-based Clinical Practice Protocol of Physical Restraints by Adaptation Process for Patients in a Geriatric Hospital (요양병원 입원 노인을 위한 신체 억제대 프로토콜의 수용개작)

  • Park, Mi Hwa;Sohng, Kyeong-Yae
    • The Korean Journal of Rehabilitation Nursing
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    • v.19 no.2
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    • pp.118-127
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    • 2016
  • Purpose: This study was to develop an evidence-based clinical practice protocol of physical restraints by adaptation process for patients with a geriatric hospital. Methods: Protocol adaptation process was conducted in accordance with manual for guideline adaptation version 1.0 by ADAPTE collaboration. Results: The adapted physical restraint protocol was consisted of 3 domains and 37 recommendations. The number of recommendations in each domain were: 7 nursing assessment, 19 nursing intervention, and 11 nursing evaluation. More than half (56.8%) of the recommendations were rated as grade B, 37.8% as grade C, and 5.4% were rated as grade D. Conclusion: The adapted physical restraint protocol is expected to contribute as an evidence-based clinical practice protocol for healthcare workers in geriatric hospitals for reducing and improving efficiency of appropriate physical restraints use.

A Computer Simulation Study on the Separation Process for Electronic Grade, Highly Pure Carbon Dioxide through a Cryogenic Distillation (심냉 증류를 통한 전자급 고순도 이산화탄소의 분리 공정에 대한 전산 모사 연구)

  • ILSU PARK;HUNGMAN MOON;JUNGHO CHO
    • Transactions of the Korean hydrogen and new energy society
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    • v.34 no.1
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    • pp.83-89
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    • 2023
  • In this study, a computer simulation work has been performed for the separation of electronic grade highly pure carbon dioxide more than 7 N purity through a cryogenic distillation process. For the cold utility as a cooling medium for a condenser of the cryogenic distillation column, propylene was utilized as a refrigerant in the vapor-recompression refrigeration cycle. Through this work, it was concluded that the cryogenic distillation column with two stage compression and refrigeration cycle were essential to obtain a highly-pure liquefied CO2.