• Journal of the East Asian Society of Dietary Life
• /
• v.27 no.2
• /
• pp.137-147
• /
• 2017

This study aimed to evaluate the necessity of updating current nutritional standards for school lunch programs in Korea. The study was performed both theoretically and practically considering the present physiques and nutrient intakes of school students. Theoretically, adequacy of types of nutrients and nutrient reference values were analyzed. Specifically, the adequacy of the types of nutrients were reviewed by applying the same selection procedures used in the 2007 revision of current standards in order to evaluate the necessity of updates. The nutrient reference values were compared with those in the U.S., Japan, and Taiwan in terms of setting year, basic data, and setting method. Practically, a focus group interview with six school nutrition teachers was conducted to investigate any operational difficulties in applying the current standards to school foodservices in Bucheon on October 1, 2015. As a result, nine types of nutrients were decided, which excluded protein and thiamin from the current ones. The nutrient reference values needed updating toward more adequate levels by reflecting more various and recent basic data considering daily nutrient intakes and the actual percentages of intakes from lunches of school students. The results showed that school nutrition teachers found it difficult to apply the current standards to school foodservices, especially as school level increased from elementary through middle to high schools mainly due to protein and calcium. Overall, the study results imply that the current nutritional standards for school lunch programs in Korea need updating to reflect the current physiques and actual nutrient intakes of school students.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.5
• /
• pp.1149-1154
• /
• 2010

Liquid chromatography/mass spectrometry using isotope dilution method has been established as a primary method for the measurement of cortisol in human serum. Verification of this method was accomplished by the participation in Consultative Committee for Amount of Substance-Metrology in Chemistry (CCQM) pilot study. Two levels of cortisol certified reference materials were prepared and certified by the established method. They were used as sample materials for the proficiency testing. The expanded uncertainty in the measurement of cortisol in human serum was approximately 1.2% at 95% confidence level. The results of the proficiency testing showed a good precision among the participants, but some bias to the certified values. This means that commercial field laboratories should keep traceability chain to SI unit through available reference measurement procedures and/or available reference materials.

• Analytical Science and Technology
• /
• v.16 no.1
• /
• pp.82-89
• /
• 2003

Isotope dilution mass spectrometry (IDMS) was applied to the determination of Ni, Cr, Mo in low alloy steel reference materials. The Mo isotope ratio measurement was performed by dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP/MS) using ammonia as a reaction cell gas. In the case of Ni and Cr measurement, all data were obtained at medium resolution mode (m/${\Delta}m=3000$) of double focusing sector field high resolution inductively coupled plasma mass spectrometry (HR-ICP/MS). For the method validation of the technique was assessed using the certified reference materials such as NIST SRM 361, NIST SRM 362, NIST SRM 363, NIST SRM 364, NIST SRM 36b. This method was applied to the determination of Ni, Cr and Mo in low alloy steel sample (CCQM-P25) provided by NMIJ for international comparison study.

• Bulletin of the Korean Chemical Society
• /
• v.32 no.4
• /
• pp.1365-1367
• /
• 2011

• Journal of the Ergonomics Society of Korea
• /
• v.30 no.5
• /
• pp.637-644
• /
• 2011

Objective & Background: When applying various evaluation tools that analyze work posture risk through observation, accurate measurement of body flexion angle is very important. Method: This study investigated differences and appropriateness of 5 different existing reference points commonly used in the analysis of the work posture. Twenty five ergonomist and trained professionals were participated in this study. A Same flexion angle was utilized for the evaluation of risk assessment of musculoskeletal disorders using five different reference points to investigate the degree of difference between them. To investigate how different the observers' preferred flexion angle measuring methods were compared to the ISO 11226 Reference Posture, a virtual body model was constructed using the Poser 6.0 program. Six types of body flexion postures were constructed, and since neck flexion differs according to body angle, five types of neck flexion postures were constructed with the trunk bending $20^{\circ}$ forward, making up a total of 30 virtual flexion postures. Results: Results showed that the observers used personally preferred reference points instead of reference points recommend in the evaluation tools. Also the results revealed the their seems to be 6 types of flexion angle for the trunk and 11 types of measurement methods for the neck flexion angle in the form of personally preferred reference points. The results showed that a mean difference of $14^{\circ}$($4{\sim}23^{\circ}$) occurred in the trunk, and a mean difference of $20^{\circ}$($-8{\sim}51^{\circ}$) occurred in the neck. To increase accuracy when using the 5 evaluation tools in combination, the ISO 11226 standards, observers' preferred flexion posture standards, and common flexion posture standards of the evaluation tools were compared with the reference points of the 5 evaluation tools. Results showed considerable variance in angle difference for each evaluation tool. Conclusion: According to the results of this study, considering the angle difference between the flexion angle reference points of the evaluation tool and the reference points selected by the observers, it is concluded that instead of personally preferred reference points, the standardized reference points to enhance the accuracy and the objectivity. Application: The result of this study can be used as reference guide to develop the standardized reference point in the future.

• Bulletin of the Korean Chemical Society
• /
• v.26 no.3
• /
• pp.440-446
• /
• 2005

A method is described for the determination of dibutyltin (DBT) in sediment by isotope dilution using liquid chromatography inductively-coupled plasma/mass spectrometry (LC-ICP/MS). To achieve the highest accuracy and precision, special attentions are paid in optimization and evaluation of overall processes of the analysis including extraction of analytes, characterization of the standards used for calibration and LC-ICP/MS conditions. An approach for characterization of natural abundance DBT standard has been developed by combining inductively-coupled plasma/optical emission spectrometry (ICP/OES) and LC-ICP/MS for the total Sn assay and the analysis of Sn species present as impurities, respectively. An excellent LC condition for separation of organotin species was found, which is suitable for simultaneous DBT and tributyltin (TBT) analysis as well as impurity analysis of DBT standards. Microwave extraction condition was also optimized for high efficiency while preventing species transformation. The present method determines the amount contents of DBT in sediments with expanded uncertainty of less than 5% and its result shows high degree of equivalence with reference values of an international inter-comparison and a certified reference material (CRM) within stated uncertainties.

• The Bulletin of The Korean Astronomical Society
• /
• v.46 no.2
• /
• pp.76.3-77
• /
• 2021

GMT secondary mirror system consists of 7 segmented adaptive mirrors. Each segment consists of a thin shell mirror, actuators and a reference body. The thin shell has a few millimeters of thickness so that it can be easily bent by push and pull force of actuators to compensate the wavefront disturbance of light due to air turbulence. The one end of actuator is supported by the reference body and the other end is adapted to this thin shell. One of critical role of the reference body is to provide the reference surface for the thin shell actuators. Therefore, the reference body is one of key components to succeed in development of GMT ASM. Recently, Korea Research Institute of Standards and Science (KRISS) and University of Arizona (UA) has signed a contract that they will cooperate to develop the first set of off-axis reference body for GMT ASM. This project started August 2021 and will be finished in Dec. 2022. The reference body has total 675 holes to accommodate actuators and 144 pockets for lightweighting. The rear surface has a curved rib shape with radius of curvature of 4387 mm with offset of 128.32mm. Since this reference body is placed just above the thin shell so that the front surface shape needs to be close to that of thin shell. The front surface has a concave off-axis asphere, of which radius of curvature is 4165.99 mm and off-axis distance is about 1088 mm. The material is Zerodur CTE class 1 (CTE=0.05 ppm/oC) from SCHOTT. All the actuator holes and pockets are machined normal to the front surface. It is a very complex challenging optical elements that involves sophisticated machining process as well as accurate metrology. After finishing the fabrication of reference body in KRISS, it will be shipped to UA for final touches and finally sent to Adoptica in Italy, in early 2023. This paper presets the development plan for the GMT ASM Reference Body and relevant fabrication and metrology plans.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.4 no.2
• /
• pp.112-121
• /
• 2001

From the beginning of 1990s, the leading countries, especially United States, are trying to develop dual-use technology which can be used for both military and commercial purpose, and to improve the efficiency of management system in logistics and procurements. Considering the global trends, Department of Defence has been seeking for solutions as to how to reform military specifications, and launched specification unification projects. As a result of the project, a series of dual-use standards for hardwares are being developed in the form of Korea Industrial Standards(KS standards). However, there are many of foreign standards, which are not readily interpretable by users, referenced in the standards. In this study, needs for the conversion of referenced foreign standards to KS standards are reviewed and the appropriate approaches as to the conversion are suggested.

• Journal of Korean Society for Atmospheric Environment
• /
• v.22 no.6
• /
• pp.922-928
• /
• 2006

An absolute absorption cross section of benzene was measured with a spectrometer system including a mono-chrometer and a grating in the wavelength region of $240{\sim}280nm$ under the atmospheric pressure and room temperature in the laboratory. A certificated reference benzene gas ($98{\mu}mol/mol$ in $N_2$) was used to measure its absorption cross section. A 710 mm cell with a quartz window and a 150 W Xe arc lamp were employed. The magnitude of absorption cross section of $1.41{\times}10^{-18}cm^2$ was lower than that of the reference spectra ($2.5{\times}10^{-18}cm^2$) of high resolution spectrometer, Total measurement uncertainty was estimated to be 4.0%.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2014.05a
• /
• pp.60-61
• /
• 2014

the reference values are high, because the Korean construction standards quote the foreign construction standars indiscriminately. Therefore ten experts were consulted to draw the items about the machine equipment construction standards for project cost saving in this study.