• Journal of the Korea Concrete Institute
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• v.16 no.6 s.84
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• pp.833-840
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• 2004

Among non-destructive tests for compressive strength, rebound number test and pulse velocity test are the most widely used methods. However, the non-destructive tests mostly used in Korea was developed by foreign country. Therefore, it is unreasonable to directly apply them to concrete structures in Korea. In accordance with the suggestion of Institute of Architecture in Japan for rebound number test, a compressive strength is calculated by the mean value of 20 hit points without being considered standard deviation. Furthermore, there is no regulation on the number of measurements required for measuring compressive strength by pulse velocity test. This study, therefore, reviewed the rebound number test and pulse velocity test by chi-square, and suggested the minimum number of each test. As a result, the minimum number that falls within range of reliability for rebound number test and pulse velocity test are 11 and 7, respectively. If abnormal values are processed as missing and test groups are assumed to be arrayed in cross by considering changes in quality of actual concrete structures, 20 times and 9 times are appropriate for rebound number test and pulse velocity test, respectively.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.4
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• pp.342-354
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• 2008

Some statistical characteristics of deepwater waves along the Korean coast have been investigated using various sources of wave measurement and hindcasting data. For very large waves comparable to design waves, it is recommended to use the average value of the empirical formulas proposed by Shore Protection Manual in 1977 and by Goda in 2003 for the relation between significant wave height and period. The standard deviation of significant wave periods non-dimensionalized with respect to the mean value for a certain significant wave height varies between 0.04 and 0.21 with a typical value of 0.1 depending upon different regions and different ranges of significant wave heights. The mean and standard deviation of the principal deepwater wave direction are presented at the 106 coastal grid points along the Korean coast. For relatively large waves, the probability density function of the directional spreading parameter $s_{max}$ is expressed as a lognormal distribution. The most suitable frequency spectrum in the Korean coast is the TMA spectrum. The probability density function of the peak enhancement factor $\gamma$ is also expressed as a lognormal distribution, with its mean value of 2.94, which is close to the value in the North Sea.

• Analytical Science and Technology
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• v.11 no.2
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• pp.112-119
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• 1998

A Siemens SemiQuant (SSQ) 3000 program, a precalibrated 'standardless' analytical program handling up to 90 elements, was evaluated for the fast analysis of various types of reference materials using a wavelength dispersive X-ray spectrometer. Various types of standard reference materials such as metal discs, metal chips, and geological materials in powder form were analysed and it took 23 minutes of measuring time for 75 elements. Measurements of geological reference materials using different sampling methods were carried out and their data were interactively evaluated. The analysis of materials of a known matrix concentration such as stainless steels provided higher precision value compared to totally unknown samples. The analyses of materials prepared as pressed pellets or fused glass beads provided higher precision values compared to the measurement of loose powders with a foil on the sample surface and helium operation, though their sampling procedures were more complicate and took more time. Since very light elements such as boron, carbon, and oxygen have a strong influence on the matrix effects and also on the calculation of effective matrix corrections, the rhodium Compton check was applied to verify the reliability of the defined light element concentrations of light matrix materials and the defined major sample compounds. Failure of defining correct matrix resulted in an unoptimized matrix correction and therefore in the wrong calculation of the element concentration.

• The Korean Journal of Pesticide Science
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• v.11 no.4
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• pp.299-304
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• 2007

Surveying, laboratory and field trial were performed to elucidate the causes of non-spinning syndrome of silkworm, Bombyx mori, abnormal symptoms of silkworm instars observed in certain sericultural fanning region. Mortality and growth of silkworm was still influenced by feeding the mulberry leaves sprayed with 10,000 fold diluted solution of standard spray of diflubenzuron WP (25%). Mortality and growth of silkworm fed with diflubenzuron-sprayed mulberry leaves with recommended spray solution were entirely affected even six weeks after spraying irrespective to the instars. Larval period of 5th instar and cocooning duration of silkworm was not affected in case 50m of buffer zone has maintained in near-by orchard field sprayed with diflubenzuron WP (25%). However, survival rate of pupae was not influenced in case 100 m of buffer zone has kept. Insect growth regulating insecticides were required to keep a certain distance of buffer zone when sprayed with water-diluted solution, 100 m from the application site at least in order to prevent contamination of the spraying drift by the chemicals.

• Journal of Navigation and Port Research
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• v.35 no.1
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• pp.31-38
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• 2011

With today's continuous increase of both seaborne trade and foreign crew boarding ships, it is necessary to study the standardization of Marine English with respect to Aids to Navigation(AtoN) for the safety of ships. After reviewing the organization of the standard council of the equipment and article of AtoN, the standardization of various types of AtoN was not capable of meeting by the only existing council's activities. For on-the-job progress, it was necessary for the subcommittee to be composed by types of AtoN. It is thus desirable to the integrated approach to the combination of the civil, the public, academic circles and research institutes, which harmonized the council's flexibility and professionalism in the composition of the members. Subjects, levels and targets in each course were presented from results of the study on the standardization scheme of Marine English related to AtoN. The ET steps were classified by the difficult degree to which the principles of interpretation and communication were applied. This study contributed to the scheme that was firstly established to solve the problem of the audiovisual English ET due to the lack of the professionalism of the existing marine affairs by presenting the standardization scheme of Marine English prior to the institutional reform related to AtoN.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.2
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• pp.233-238
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• 2008

This experiment was conducted to enhance the colored potatoes utilization and to determine the biological activity of colored potato extracts. In order to understand the factors responsible for the potent anti-oxidant ability of colored potatoes, it has been evaluated for anti-oxidative activity using oxygen radical absorbance capacity (ORAC) assay. 'Hongyoung' extract was significant anti-oxidant activities in ORAC assay. About two-fold higher radical absorbance capacity was found in 'Hongyoung' compared to that in 'Jayoung'. The ability of 80% ethanol extracts from colored potatoes to influence the inhibitory activity of nitric oxide (NO) and nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) has also been investigated. The various therapeutic benefit claims in the new functional medicinal usage of colored potatoes ascribed to the phenolic compounds and anthocyanin. This result revealed that the extracts of colored potatoes are expected to be good candidate for development into sources of free radical scavenger or COX-2 inhibiting agents.

• Journal of Conservation Science
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• v.32 no.4
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• pp.491-500
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• 2016

Fog is atmospheric in which tiny drops of water vapor are suspended in the air near the ground. Its form, occurrence, etc., change according to the temperature, relative humidity, wind and geographical features of the space around it. In particular, fog tends to occur near a source of water because of temperature and relative humidity difference. These days, climate change is increasingly affecting the occurrence of fog. Therefore the purpose of this study was to investigate how fog affects materials that are part of our cultural properties through outdoor exposure tests and artificial degradation. The degradation evaluation of materials as a function of fog occurrence frequency, showed that the color of metals changed noticeably, whereas dyed silk and Dancheong showed degradation on the surface and color differences but no particular tendencies. Therefore, damage prediction by color differences as a function of fog occurrence frequency was based on metal samples, which showed constant color differences. Through a comparison of the predictive value and color difference by outdoor exposure, the accuracy and applicability of the damage prediction formula was confirmed. If a more complex damage prediction formula is created, it is expected that prediction of the degree of material damage in the field would be possible.

• The Magazine of the IEIE
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• v.11 no.5
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• pp.42-50
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• 1984

국내의 다음세대 컴퓨터 개발을 위한 VLSI 설계와 CAD 분야에 대한 연구 방향을 제시한다. 연구의 목표는 국제적으로 경쟁할 수 있는 VLSI 설계능력과 백만개 정도의 트랜지스터로 자성된 회로를 경제적으로 설계하기 위한 CAD 기술과 System의 확립이다. ·새로운 회로 구조와 알고리즘에 대한 연구 · CAD 도구와 언어의 개발에 관한 첨단 CAD 기술개발연구 · VLSI 설계에 필요한 CAD 도구 이용과 개발에 필요한 표준 인터페이스, 네트워킹, 컴퓨팅 하드웨어. 시스템 소프트웨어에 대한 연구등의 부분으로 크게 나눌 수 있다. 이용 가능한 CAD system을 평가하고 개선하며 첨단 CAD에 대한 소프트웨어와 하드웨어에 대해 · 컴퓨팅 하드웨어 · 프로그램 분위기 · 네트워킹 능력 ·자료 교환을 위한 표준인터페이스 등에 관해 조사분석도 병행한다. CAD에 관한 세부적인 연구 과제는 · 시스템 사양언어 · 설계 검증 ·시스템시뮬레이션· 설계 합성 · 설계 해석· 설계 방법론·디바이스와 공정 모델링 프로그램 등이다. 고속 계산용 VLSI에 관한 구조와 알고리즘은 행렬 계산을 위한 ·분산 배열 처리 회로 ·시스토릭 (Systolic) 배열 회로 ·셀률라(Cellular) 논리 회로 · 3차원 배열 회로 와 · 비규칙적 계산 알고리즘을 갖는 VLSI가 있다. VLSI설계훈련과 CAD 기술 축적을 위해 CAD enter를 설립하여 전국적인 CAD 네트워킹을 관계 연구소와 여러 대학에 가설하며, MPC 계획을 추진한다. VLSI설계 가능성이 입증되면 VLSI 설계능력을 더욱 향상 시키기 위해 0.5∼1.0mm기술의 silicon faundary를 설립한다. 연구 개발 조직은 대학, 산업체. 연구소가 삼위일체가 되어 수행될 수 있도록 연구 개발 위원회를 설치 운영하며 경쟁적이며 경제적으로 연구 업무를 집행하는 것이 바람직하다.았다.형질에 관여하는 귀전자에 미치는 기구에 대하여 검토할 여타가 있다고 보여진다. 분해능의 특징으로 미루어 앞으로는 레이저를 이용한 계측 방법이 그 주류를 이룰 것으로 사료된다. 우선 본 해설은 기체의 온도 및 농도의 광학적 측정방법중 Raman산란광 검출법에 대하여 실제로 측정하는 입장에서 간단히 소개한다.lity)이, 높은 $GA_3$함량에 기인된다'는 주장은 본실험(本實驗)으로 부인(否認)되었다. 따라서, 응용학적(應用學的) 측면에서 고려해 볼 때, 리베스식물(植物)의 육종기간 단축을 위한 모든 화아분화(花芽分化) 촉진 조치는 P.J.-식물(植物)이 20. node이상 생육하였을 때 취하는 것이 효율적인 것으로 결론 지어진다.앞당겨진 7月 셋째 週였다. 8. Culex (Culex) tritaeniorhynchus summoro년의 最大發生 peak는 1981年, 1982年 모두 8月 둘째 週였다. 9. Anopheles (Anopheles) sinensis의 最大發生 peak는 1981年에 7月 다섯째 週, 1982年은 2週 앞당겨진 7月 셋째 週였다. 10. 重要 3種의 最大 peak를 比城하면 Culex (Culex) pipiens pallens와 Anopheles (Anopheles) sinensis는 1981年과 1982年 모두 最大 peak時期가 同一하였으며, Culex (Culex) tritaeniorhynchus summoro년는 2年間 모두 8月둘째 週에 나타났다.osterior to manubrium and anterior to aortic arch) replacing the normal mediastinal fat. (2) In benign thymoma, the marging of the mass was smooth and the normal fat

• Journal of Food Hygiene and Safety
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• v.34 no.5
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• pp.480-488
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• 2019

To ensure the safety of products containing omega-3 fatty acids, twenty fish and algae oil omega-3 products available in a Gyeonggi Province, South Korea market were analyzed for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) content, as well as for oxidative status. Of the tested products, 90% complied with the CODEX/FAO fish oil standards on a p-anisidine value (p-AV) limit of 20, and 80% complied with the CODEX/FAO fish oil standards on the TOTOX limit of 26, respectively. Fully 100% of the products complied with EPA/DHA content levels. In addition, 90% of the tested products met with a peroxide value (PV) limit of 10 meq/kg while 95% of products were within the a p-AV limit of 30. Also, 95% of the products had a calculated TOTOX value of 50, which is lower than the stringent limits used by the European and British Pharmacopeia and Australian authorities.

• Analytical Science and Technology
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• v.20 no.1
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• pp.25-32
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• 2007

The measurement methods for total nitrogen in wastewater containing a high concentration of nitrogen were evaluated. (1) The UV spectrophotometry, (2) reduction-distillation Kjeldahl, (3) total Kjeldahl nitrogen, and (4) ion chromatography methods were applied. The experimental procedure of the UV spectrophotometric method was simple, but it produced large errors deriving from the dilution of samples and calibration standards. While, the reduction-distillation Kjeldahl method didn't need dilution, but the amount of Devarda's alloy and NaOH lead to large errors up to 50 mg/L. The levels of total nitrogen measured by each method were as follows: reduction-distillation Kjeldahl ($568.6{\pm}38.7mg/L$) > UV spectrophotometry ($527.3{\pm}9.6mg/L$) > total Kjeldahl nitrogen method ($494.7{\pm}21.4mg/L$) > ion chromatography method ($417.9{\pm}7.3mg/L$). Therefore, the reduction-distillation Kjeldahl method is preferred for wastewater with the high concentration of nitrogen. Optimal conditions for each experimental procedure, however, are needed to be confirmed, and the Standard Operation Procedure (SOP) for total nitrogen is required for reliable measurements.