• Journal of Bio-Environment Control
• /
• v.26 no.4
• /
• pp.301-309
• /
• 2017

This study was conducted to provide basic data needed to calculate the crop loads for the greenhouse design. Four countries' crop loads for greenhouse structures were compared and the crop loads were measured directly and analyzed for various greenhouse crops, including tomato, strawberry, cucumber, and eggplant. According to the analysis results of four country's standards for the design crop loads, it was judged that the new design crop loads suit for greenhouse crops in our country should be suggested because our standards just used the design crop loads of other countries. The maximum crop loads per plant of tomato, cucumber, eggplant, and strawberry were 3.9, 0.75, 1.9 and $2.1kgf{\cdot}plant^{-1}$, respectively. The crop load per unit area of tomato was $8.5kgf{\cdot}m^{-2}$, which was much greater than the cucumber and eggplant's crop load of 2.1 and $2.4kgf{\cdot}m^{-2}$ respectively. The crop loads of tomato and cucumber, suggested by the greenhouse structure design standard of Korea, is $15kgf{\cdot}m^{-2}$, which is far greater than the values suggested by this research. It was judged that this was because our standard just used the Dutch standard, our crop load standard should be reviewed considering this difference. The crop load of strawberry, including the growing bed, was $21.0kgf{\cdot}m^{-2}$, which was much greater than the crop load in the Dutch standard.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.43 no.12
• /
• pp.1108-1115
• /
• 2015

In this study, correlation equations were arranged about mass flow rates of oxygen and volume flow rates of helium using a mouthpiece method. The mouthpiece method can reduce examination cost by using similar empirical formula. Instead of liquid oxygen, in the mouthpiece method, gas helium can be measured in order to determine the leakage amount of liquid oxygen conveniently. Experiment was conducted and compared to understand leakage amount relation between the helium and the oxygen for prototype item under a room and a cryogenic temperature conditions. The leakage volume flow rate [$A.m{\ell}/s$] of the helium was 174 times higher than mass flow rate [g/s] of the oxygen leakage at liquid state. The derived correlation equations were verified using data from the National Institute of Standards and Technology (NIST).

• Journal of Radiation Protection and Research
• /
• v.19 no.2
• /
• pp.133-145
• /
• 1994

Recently, the Ministry of Science and Technology issued a Ministerial Ordinance (No 1992-15) about the technical criteria on personnel radiation dosimetry. In today's climate, it is important to demonstrate and document that the processor's systems and services to others meet national standards of quality. The purpose of this study is to verify the performance of the Teledyne PB-3 personnel dosimetry system that is generally used in Korea Atomic Energy Research Institute(KAERI) by intercomparison with Oak Ridge National Laboratory. The KAERI has been participated in this personnel dosimetry intercomparison study(PDIS) program since 1991 and it could be possible to test and calibrate personnel monitoring system. This report presents a summary and analysis of by about 50 dose equivalent measurements reported for PDIS-16 through 18 (1991 -1993) with emphasis on neutron dose equivalent sensitivity, accuracy and precision. Relationships of the PDIS results to occupational neutron monitoring and methods to improve personnel dosimetry performance are also discussed.

• Journal of the Korean GEO-environmental Society
• /
• v.23 no.11
• /
• pp.5-11
• /
• 2022

The objective of this study is to evaluate the mechanical properties of high-flowable retaining wall material (RWM) incorporated with ground granulated blast-furnace slag (SG) and steel fiber (SF) based on a comparison with those of ordinary portland cement (OPC). To produce the specimens of RWM, some chemical agents such as superplasticizer (SP), air-entrained agent (AEA) and viscosity modifying agent (VMA) are added in the fresh RWM. The compressive, split tensile and flexural strength measurements were performed on the hardened RWM specimens. Additionally, surface electric resistivity and absorption tests according to ASTM standards were carried out at predetermined periods after water curing. It was found that the mechanical properties of slag cement concrete (SGC) RWM mix are better than those ordinary portland cement concrete (OPC) RWM mix. The effect of SF is remarkable to improve the mechanical properties of RWM mixes. It is noted that the usage of SG shows a beneficial effect to resist water penetration as well as long-term strength development of RWM mixes.

• Journal of Nutrition and Health
• /
• v.13 no.1
• /
• pp.27-36
• /
• 1980

A dietary survey of 100 children, aged 5 to 6, of Y.C. Kindergarten located in Yowido apartment compound of Seoul, was conducted July 18 to August 21, 1979. The results are summarized as follows: General family environment: Ninety four percent of the subjects were from families having two to three children, without grandparents in the home. One hundred percent of fathers were educated at or above the college level, while 83.9% of mothers had completed college. Mothers' ages ranged from 30 to 40 years, with 58% in the $31{\sim}35$ age bracket. Nearly 60% of the fathers were office and government employees, 10% were professors and teachers, 30% were engaged in businesses and other work, while 91.3% of mothers were unemployed. Anthropometric measurements: Mean values of standing height, body weight, girth of head and girth of chest, ranged from the 75th to the 90th percentile of Korean standards. None of the subjects had anthropometric indicators below the 5th percentile, representing the malnutrition borderline, of the Korean standards; while 12%, 24%, 17% and 14% of subjects supposed the 97th percentile in standing height, body weight, girth of head, and girth of chest, respectively. Furthermore, 58% of subjects exceeded Jelliffe's standard in arm circumferences; 60%, in triceps skinfold thickness; and 14.5% of subjects exceeded 120% of the latter standard. From this data, a certain number of these children were judged to he rather overweight. Dietary intake: Mean intake per day of energy and of nutrients, excluding iron, reached or exceeded Korean recommended dietary allowances. The energy input ratio of carbohydrate: protein: fat was 61.4 : 13.2 : 25.4, showing lower dependance on carbohydrates and higher dependance on fat for energy needs, compared with the average for Korean children of the same age group. Mean FAO-protein score of each subject's diet was shown to be as high as 90.6. Energy intake was divided among breakfast, lunch, and evening meal, on the average, in a ratio of 19.6 : 24.1 : 23.0. Approximately 33.3% of the daily caloric intake came from the snacks. Nutrition Knowledge of mothers: Nutrition knowledge of mothers was highly scored. Mothers' self-evaluations of their knowledge of nutrition was highly correlated with attitudes toward nutrition behavior.

• Korean Journal of Optics and Photonics
• /
• v.19 no.1
• /
• pp.54-59
• /
• 2008

We report on the measurements of absorption spectra from acetylene ($^{12}C_2H_2$) and hydrogen cyanide ($H^{13}C^{14}N$) for wavelength reference in the C-band (conventional band) region using a supercontinuum optical source generated from a mode-locked $Cr^{4+}$:YAG laser. The center wavelength of the mode-locked $Cr^{4+}$:YAG laser was 1510 nm and the pulse duration was 75 fs at 100 MHz repetition rate. The supercontinuum source achieved a flatness of ${\pm}5dB$ over a wavelength range of more than 400 nm, using a 20 m long photonic crystal fiber. The measured absorption spectra from acetylene ($^{12}C_2H_2$) and hydrogen cyanide ($H^{13}C^{14}N$) had more than 50 lines and were analyzed for wavelength standardization.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.18 no.1
• /
• pp.158-162
• /
• 2014

Purpose: Reference material (RM) is defined as material that is safe and homogeneous enough about specified characteristic that is made with a purpose of using test of measurement or nominal characteristic. Certified reference material (CRM), which is issued by authorized organization, is defined as reference material that provides characteristic value, link uncertainty and retroactivity. The purpose of this paper was to evaluate recovery of radioimmunoassay by Certified Reference Material enclosed with a certificate and therefore to enhance reliability of test. Materials and Methods: WHO certified reference material is purchased from NIBSC (National Institute for Biological Standard and Control, United Kingdom) and made of 3 levels that are C-1 (low concentration), C-2 (medium concentration) and C-3 (high concentration) and measured for kit at the Seoul National University Hospital. Recovery rate is evaluated after measurement at four different days. Results: Recovery rate results using WHO certified reference material are T4 90%, Ferritin 88%, PSA 94%, Prolactin 99%, AFP 94% and TSH 93%. Conclusion: A procedure that appropriate accuracy, precision, specificity, sensitivity, reproducibility, and validate on the subject of kit for radioimmunoassay is essential. Recovery rate assay as extraction efficiency of analysis process is percent about already measuring results of analysis result after all measuring process. This is very important assessment standards of performance evaluation of immunoassay kit. Recovery rate results of 6 type used WHO CRM are satisfactory to 88~99%. This demonstrates that the radioimmunoassay is a very accurate measurement, which is very effectively utilized in clinical practice.

• The Journal of the Acoustical Society of Korea
• /
• v.36 no.5
• /
• pp.329-337
• /
• 2017

In USA and UK, the standards of both reverberation time and background noise level have been established for the appropriate aural environment in classrooms. In order to realize this, guidelines for architectural planning and interior finishing have been also suggested. However, in Korea, there has hardly been any guidelines for satisfying background noise criteria and investigation about sound insulation performance of current walls of classrooms. The present study investigates the structure of outer wall and walls between classrooms of two middle schools in order to analyze the sound insulation performance against both exterior and interior noises. Acoustic parameters including transmission loss, standardized sound level difference, and signal to noise ratio have been measured and analyzed for sound insulation performance of walls and flanking noises. As a result, concerning the walls in between classrooms, it was found that walls of dry construction have greater sound insulation performance rather than the walls of wet construction especially in mid and high frequency bands. Also, It was revealed that thermopane, insulated pair glass, of outer walls, has greater sound insulation performance than the double window consisted of two single pane glass. Regarding flanking noises, the standards were exceeded when all windows, or windows and doors front onto corridor were opened. It denotes that students could be disturbed with the sound transmission by the interior noises.

• Journal of Korean Society of Forest Science
• /
• v.104 no.3
• /
• pp.352-359
• /
• 2015

This study was conducted to evaluate how the special protection area designations of degraded trails effect on the soil and vegetation recovery of degraded trails. The study areas were established on an opened trail and a 16-year closed trail, which was prohibited to enter after the designation as a special protection area for recovery, at Bukhansan National Park. Soil core sampling and measurements of vegetation cover were performed to compare soil and vegetation properties of the trails. Soil bulk density increased and soil water total nitrogen decreased on the opened trail, while no significant differences were found on bulk density, soil water, total nitrogen, acidity, and organic matter on the closed trail. On the opened trail, vegetation cover was seemed to be degraded, because vegetation litter cover ratio was low and barren rock cover ratio was high. On the closed trail, litter rock barren cover ratio of the closed trail was recovered, but only limited recovery was found on vegetation cover by applying environmental damage condition rating class. In conclusion, the closed trail was recovered by designation of special protection area, while difference in recovery progress of soil and vegetation was found. Therefore, designation of special protection area of degraded area should be based on scientific basis of recovery characteristics of the area. In order to improve the effectiveness of special protection area system, further specific standards for special protection area designation and management would be needed, considering ecological and social importance of target areas.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.8 no.3
• /
• pp.113-117
• /
• 2006

The main objective of this study is to provide numerical guideline for the development of educational environment about girls in the adolescent period ($14{\sim}16\;years$) through comparison and analysis on physical standards of nation (report published in 1997). The sample for this work was chosen from data which were collected and measured by Size Korea during two years ($2003{\sim}2004$). In order to analyze feature of the somatotype of girls in the adolescent period, analysis was performed about 858 subjects on 22 body parts such as height (6 parts), width (3 parts), thickness (3 parts), circumference (4 parts), length (5 parts) and body weight. For the specific comparison on somatotype, $R\'{o}hrer$ index and Mollison's comparison graph were used. The result of this study enables us to know the important factors which affect the somatotype of girls in the adolescent period ($14{\sim}16\;years$) and will be utilized in various fields such as design of classroom, student uniforms, facilities and equipments for education, etc. According to the result of this study, future research will be focused on not only development of educational facilities but also uniform patterns of female students. In addition, the research on development of equipments which are being used by girls in the adolescent period ($14{\sim}16\;years$) will be another future research.