• Title/Summary/Keyword: Primary standards

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Chamber to Chamber Variations of a Cylindrical Ionization Chamber for the Calibration of an $^{192}Ir$ Brachytherapy Source Based on an Absorbed Dose to Water Standards (물흡수선량 표준에 기반한 $^{192}Ir$ 근접치료 선원 교정 시 원통형 이온함의 이온함 간 변화)

  • Kim, Seong-Hoon;Huh, Hyun-Do;Choi, Sang-Hyun;Kim, Chan-Hyeong;Min, Chul-Hee;Shin, Dong-Oh;Choi, Jin-Ho
    • Progress in Medical Physics
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    • v.20 no.1
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    • pp.7-13
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    • 2009
  • This work is for the preliminary study for the calibration of an $^{192}Ir$ brachytherapy source based on an absorbed dose to water standards. In order to calibrate brachytherapy sources based on absorbed dose to water standards using a clyndirical ionization chamber, the beam quality correction factor $k_{Q,Q_0}$ is needed. In this study $k_{Q,Q_0}s$ were determined by both Monte carlo simulation and semiexperimental methods because of the realistic difficulties to use primary standards to measure an absolute dose at a specified distance. The 5 different serial numbers of the PTW30013 chamber type were selected for this study. While chamber to chamber variations ran up to maximum 4.0% with the generic $k^{gen}_{Q,Q_0}$, the chamber to chamber variations were within a maximum deviation of 0.5% with the individual $k^{ind}_{Q,Q_0}$. The results show why and how important ionization chambers must be calibrated individually for the calibration of $^{192}Ir$ brachytherapy sources based on absorbed dose to water standards. We hope that in the near future users will be able to calibrate the brachytherapy sources in terms of an absorbed dose to water, the quantity of interest in the treatment, instead of an air kerma strength just as the calibration in the high energy photon and electron beam.

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Drop Simulation of Puppy Robot by Toys Safety Standards (완구 안전검사 기준을 적용한 강아지 로봇의 낙하 해석)

  • Chung Tae-Eun;Kim Jun-Gi;Sin Hyo-Chol
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.710-713
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    • 2005
  • Many impact or drop test researches of home appliances are published, but those of toys cannot be found easily. External impacts are the primary causes of fracture of toys. For impact proof design, the finished product should pass an impact test after molding design. There are several international toy safety standards or requirements such as US CPSC(Consumer Product Safety Commission), ASTM F963-96a, EN71 and so on. The puppy robot which patrols around the house, namely, the watchdog was selected to investigate toy safety because it has considerable weight and outer panels are made of plastics. First the model of watchdog robot was obtained by 3 dimensional scan. Surface data can be generated from 3D polygon data of the watchdog. A reliable drop simulation method for the watchdog was established using Pam-crash program according to Korean toy safety standards. When there is a low impact allowance value, the molding design should be reinforced or changed. It was found that the maximum impact stress reaches the ultimate stress of panel material.

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Realization of silver fixed-point and application for the high temperature platinum resistance thermometry using the gas-pressure controlled sodium heat-pipe furnace (가스압력조절식 나트륨 열관전기로를 이용한 은 고정점 실현과 고온백금저항온도 계측에의 응용)

  • Gam, K.S.;Choi, I.M.;Yang, I.;Kim, Y.G.
    • Journal of Sensor Science and Technology
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    • v.18 no.2
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    • pp.116-121
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    • 2009
  • Pressure-controlled sodium heat pipe furnace was designed and fabricated, and its characteristics was investigated. Pressure control system was controlled within ${\pm}0.5\;Pa$ at 150 kPa and the stability of pressure was decreased to ${\pm}2.5\;Pa$, when the pressure-controlled system connected with the heat pipe. The melting curve of Ag fixed-point realized well by the adiabatic method using the pressure-controlled sodium heat pipe furnace and its accuracy showed ${\pm}2.27\;mK$ from the calculation of 20% to 80% at the plateau. The freezing curve of Ag fixed-point also realized and its plateau value was 2.23 mK lower than that of the melting curve.

Comparing the Housing Laws related to the disabled in various countries for Aging Society (고령화 사회를 위한 국내·외 장애인 주택관련법 비교연구)

  • Kim, Sang-Woon
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.18 no.2
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    • pp.7-17
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    • 2012
  • The purpose of this study is to be suggested the primary data when housing research related the disabled and the enactment are needed. For the purpose, this study compares the Housing Laws, such as state of legislation, composition and detailed standards in domestic and international. The scope of study is limited each space in 7 types, entrance, corridor, living room, bedroom, bathroom, kitchen, and balcony, then, laws related on each space are compared and analyzed. In addition, comparison of the foreign's Housing laws are focused on Switzerland, Germany, United States of America, and Japan where have systematic and organized Housing laws by in each space. This study were processed as follows: First, domestic and foreign laws are examined throughout state of legislation, composition, detailed standards, and types of the disabled. Then, housing laws that applied institutionally in each country are compared. Finally, similarities and differences of specific standards are analyzed by comparison on space in each country.

Development of an automatic measurement system for the AC-DC current transfer difference of the thermal current converter (열전형 전류 변환기의 교류-직류 전류 변환차이 자동측정시스템 개발)

  • Kwon, Sung-Won;Jung, Jae-Kap;Kim, Mun-Seog;Kim, Kye-Tae;Ryu, Je-Cheon
    • Journal of Sensor Science and Technology
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    • v.14 no.5
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    • pp.350-356
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    • 2005
  • We have developed a dual-channel type automatic measurement system to evaluate AC-DC current transfer difference of the thermal current converter(TCC) which is primary standard of AC current. The output drift effect of the TCC is minimized by measuring simultaneously the output voltages of two TCCs using voltmeter. Furthermore, the offset voltage of the voltmeter is cancelled nearly out by taking the average values of two outputs of TCCs measured with the forward-reverse directions using dual channel scanner. The uncertainties of the automatic system were 7 to $86{\mu}A/A$ for 3 mA to 10 A at 40 Hz to 20 kHz, which were evaluated by the comparisons between adjacent range of TCCs and inter-comparison with national measurement institute of Germany(PTB). The capability for ac-dc transfer difference measurement was improved by one order compared with that for the manual ac-dc measurement system.

Exploring the Improvement of Mathematics Curriculum Achievement Standards for Elementary School in Competency-Based: Focused on comparing 'Number and Arithmetic' in Korean and Australian Curriculum (초등학교 수학과 교육과정 성취기준의 역량 기반 개선 방안 탐색 : 한국과 호주 '수와 연산' 영역 비교를 중심으로)

  • Lee, Hwa Young
    • Education of Primary School Mathematics
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    • v.23 no.4
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    • pp.229-255
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    • 2020
  • In this study, considering the OECD's DeSeCo and 2030 projects, the curriculum to develop competency was expected to be more emphasized, and the evaluation standards of the 2015 revised mathematics curriculum for elementary school in Korea and the Australian curriculum were analyzed in depth. To this end, the capabilities newly emphasized in the OECD 2030 Project were examined in detail and examined how the Australian elementary school mathematics curriculum included capabilities in achievement standards and content descriptions. The achievement standards of elementary school mathematics curriculum in Korea and Australia were matched, and the contents of number and arithmetic domain were compared and analyzed, and the skill verbs included in the achievement standards were analyzed and compared to see how their competencies were reflected in the achievement standards. Based on the results of the analysis, implications for improving math achievement standards were derived to faithfully reflect the capabilities into the mathematics curriculum.

A Review of Accounting Standards for Tax Effect Accounting (세효과회계에 관한 각국의 동향)

  • Jung Moon-Hyun;Roh Hyun-Sub
    • Management & Information Systems Review
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    • v.7
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    • pp.93-111
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    • 2001
  • In this article, we perform an international overview of accounting standards for tax effect accounting(or income taxes). Specially, we compare accounting standards for tax effect accounting of U.S. and International Accounting Standards. The principal component of U.S. accounting standards for tax effect accounting is as follow. Statement of Financial Accounting Standards No. 109, Accounting for Income Taxes (SFAS No. 109) represents the culmination of a multi-year process in which Financial Accounting Standards Board (FASB) reviewed and subsequently modified the requirements for accounting for income taxes. SFAS No. 109 requires an 'asset and liability' approach for the accounting for income taxes. That is, deferred income taxes are viewed as assets and liabilities of the firm, and deferred tax expenses id determined by the current-year change in the firm's deferred tax liabilities and assets. Previously, Accounting Principles Board Opinion No. 11, Accounting for Income Taxes (APB No. 11) required a 'deferral' approach to accounting for income taxes. The primary intent of the deferral approach was to match tax expense with corresponding revenues and expenses for the year in which the revenues and expenses were recognized in the financial statement. Unlike the SFAS No. 109, APB No. 11 did not require firms to adjust deferred tax balances for subsequent events such as changes in tax rates or laws. And, the principal deference between SFAS No. 109 and the previous statement on accounting for income taxes, SFAS No. 96, is that SFAS No. 109 requires firms to recognize deferred tax assets for the tax benefits of tax credit or operating loss carryforwards, no matter how likely the firm was to realize these benefits, and this was one of the reasons for its demise.

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Using of the "Consolidated Standards of Reporting Trials:CONSORT" to heighten quality of Medical Education study (의학교육연구의 질을 향상시키기 위한 '연구보고의 표준' 의 활용)

  • Yoo, Ji-Soo
    • Korean Medical Education Review
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    • v.10 no.2
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    • pp.25-44
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    • 2008
  • Objectives: Through using of the strong research method like a Randomized Controlled Trial: RCT, we have to heighten quality of Medical Education study. I'd like to introduce "CONSORT", which stands for Consolidated Standards of Reporting Trials. Contents: Preventive Service Task Force(200l) in USA proposed Levels of evidence for enlarging evidence-based Practice: EBP. And the CONSORT was introduced, which encompasses various initiatives developed by the CONSORT Group to alleviate the problems arising from inadequate reporting of randomized controlled trials (RCTs). the CONSORT has 13 guides like these: 1. How participants were allocated to interventions 2. Scientific background and explanation of rationale 3. Eligibility criteria for participants. The settings and locations where the data were collected. 4. Precise details of the interventions intended for each group and how and when they were actually administered 5. Specific objectives and hypotheses 6. Clearly defined primary and secondary outcome measures, When applicable. any methods to enhance the quality of measurements (e.g., multiple observations, training of assessors) 7. How sample size was determined. When applicable, explanation of any interim analyses and stopping rules 8. Method used to generate the random allocation sequence, Details of any restriction [of randomization] 9. Method used to implement the random allocation sequence 10. Who generated the allocation sequence, who enrolled participants. and who assigned participants to their groups 11. Whether or not participants, those administering the interventions, and those assessing the outcomes were blinded to group assignment. If done, how the success of blinding was evaluated 12. Statistical methods used to compare groups for primary outcome(s), Methods for additional analyses, such as subgroup analyses and adjusted analyses 13. Flow of participants through each stage (a diagram is strongly recommended) Specifically, for each group report the numbers of participants randomly assigned. receiving intended treatment, completing the study protocol. and analyzed for the primary outcome. Results and Conclusion: Randomized Controlled Trial: RCT guided of CONSORT will contribute to do stronger evidence-based medical studies.

Exploring Writing Education Standards for Secondary School Science Teachers (중등 과학교사 글쓰기 교육 기준 탐색)

  • Eo, Seon-Sug;Cho, Hee-Hyung
    • Journal of The Korean Association For Science Education
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    • v.32 no.1
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    • pp.182-200
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    • 2012
  • There is growing recognition that secondary students must be given the opportunity to write in their science classrooms as well as in scientific inquiry based learning situations, yet the development of writing education standards for secondary school science teachers still needs to be addressed. The primary objective of this research was to explore the writing education standard for secondary school science teachers. The research objective was attained through the use of literature analyses. Drawing upon those results of the related literature analyses, this study suggests a list of writing education standards for secondary school science teachers. The list consists of 17 education standards and includes 42 sub-standards in total across four education areas.

Analysis of Non-compliance of Food Utensils, Containers, and Packages in Foreign Countries During 2011-2019 (2011-2019년 식품용 기구 및 용기·포장의 제외국 부적합 정보 분석)

  • Cho, Seung Yong;Lee, Ye Yeon;Cho, Sanggoo
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.27 no.3
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    • pp.141-147
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    • 2021
  • The foreign trends of noncompliance occurring frequently in food contact materials during the period of 2011-2019 was investigated by analyzing the food safety risk information DB in the National Food Safety Information Service (NFSI). A total of 2,042 cases of noncompliance of food utensils, containers, and packages were classified into 5 violation categories; administrative procedures, manufacturing and processing standards, residues and migration standards, labeling and advertising, and quality standards. This was again subcategorized according to non-compliance causative factors. The non-compliances in residues and migration standards comprised the largest proportion (76.4%) of the violative categories. The number of noncompliance information collected in 2011 was 88 cases and increased to 373 cases in 2019. A 72.8% of the non-compliance case was identified to be products of 4 countries (China 64.2%, Germany 4.0%, Japan 3.2%, and Taiwan 3.1%), those produce large quantities of containers and packaging products. During the period of 2011-2019, the number of illegal use of hazardous materials and illegal recycling of waste synthetic resins has decreased to less than one a year since 2014. On the other hand, after 2016, inconsistency of heat-resisting temperature labeling (Taiwan), non-compliance in paper container's strength standards, violation of printing standards, and the risk of consumer injury while using the products were newly reported due to the strengthening of consumer safety protection regulations. Migration of hazardous substances in synthetic polymer products such as heavy metals, melamine and formaldehyde in melamine tableware, primary aromatic amines which are colorant components in kitchenware such as ladles and spatulas, and phthalate plasticizers have been continuously reported with high frequency.