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A Study on Heavy Metal Contents in Processed Foods and Their Safety Evaluations (가공식품 중 중금속 함량 및 안전성 평가)

  • Lee, Hyo-Jung;Shim, Jee-Youn;Oh, Hyun-Suk;Jang, Mi-Ran;Lee, Yoon-Ae;Lee, Ryun-Kyung;Kim, Min-A;Lee, Sang-Min;Cho, Tae-Yong;Kang, Ho-Il
    • Korean Journal of Food Science and Technology
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    • v.44 no.1
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    • pp.21-27
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    • 2012
  • This research was carried out as a survey on the contents of lead, cadmium, and arsenic in processed foods (milk, vegetable oil, and margarine) in Korea. The limits of quantification (LOQs) were Pb 0.3 ${\mu}g/kg$, Cd 0.15 ${\mu}g/kg$, and As 0.45 ${\mu}g/kg$ for milk and Pb 0.61 ${\mu}g/kg$, Cd 0.31 ${\mu}g/kg$, and As 0.91 ${\mu}g/kg$ for vegetable oil and margarine. The recoveries were 92.6-98.0% for Pb, 91.2-98.9% for Cd, and 97.9-104.7% for As. The average levels of Pb were 2.395 ${\mu}g/kg$ for milk, and 7.656 ${\mu}g/kg$ for vegetable oil. The average levels of Cd were 0.483 ${\mu}g/kg$ for milk, and 0.380 ${\mu}g/kg$ for vegetable oil, and levels of As were 0.781 ${\mu}g/kg$ for milk, and 1.241 ${\mu}g/kg$ for vegetable oil. The results of this study showed that Pb, Cd, and As contents in the whole samples were less than the maximum residual levels in the processed foods that were specified by the Codex standard.

Evaluation of the Satellite-based Air Temperature for All Sky Conditions Using the Automated Mountain Meteorology Station (AMOS) Records: Gangwon Province Case Study (산악기상관측정보를 이용한 위성정보 기반의 전천후 기온 자료의 평가 - 강원권역을 중심으로)

  • Jang, Keunchang;Won, Myoungsoo;Yoon, Sukhee
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.19 no.1
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    • pp.19-26
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    • 2017
  • Surface air temperature ($T_{air}$) is a key variable for the meteorology and climatology, and is a fundamental factor of the terrestrial ecosystem functions. Satellite remote sensing from the Moderate Resolution Imaging Spectroradiometer (MODIS) provides an opportunity to monitor the $T_{air}$. However, the several problems such as frequent cloud cover and mountainous region can result in substantial retrieval error and signal loss in MODIS $T_{air}$. In this study, satellite-based $T_{air}$ was estimated under both clear and cloudy sky conditions in Gangwon Province using Aqua MODIS07 temperature profile product (MYD07_L2) and GCOM-W1 Advanced Microwave Scanning Radiometer 2 (AMSR2) brightness temperature ($T_b$) at 37 GHz frequency, and was compared with the measurements from the Automated Mountain Meteorology Stations (AMOS). The application of ambient temperature lapse rate was performed to improve the retrieval accuracy in mountainous region, which showed the improvement of estimation accuracy approximately 4% of RMSE. A simple pixel-wise regression method combining synergetic information from MYD07_L2 $T_{air}$ and AMSR2 $T_b$ was applied to estimate surface $T_{air}$ for all sky conditions. The $T_{air}$ retrievals showed favorable agreement in comparison with AMOS data (r=0.80, RMSE=7.9K), though the underestimation was appeared in winter season. Substantial $T_{air}$ retrievals were estimated 61.4% (n=2,657) for cloudy sky conditions. The results presented in this study indicate that the satellite remote sensing can produce the surface $T_{air}$ at the complex mountainous region for all sky conditions.

Reaction Gas Composition Dependence on the Properties of SnO2 Films on PET Substrate by ECR-MOCVD (반응가스조성이 PET기판위에 ECR 화학증착법에 의해 제조된 SnO2 박막특성에 미치는 영향)

  • Kim, Yun-Seok;Lee, Joong-Kee
    • Journal of the Korean Electrochemical Society
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    • v.8 no.3
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    • pp.139-145
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    • 2005
  • [ $SnO_x$ ] films on the flexible substrate of PET film were prepared at ambient temperature under a $(CH_3)_4Sn(TMT: tetra-methyl tin)-H_2-O_2$ atmosphere in order to obtain transparent conductive polymer by using ECR-MOCVD(Electro Cyclotron Resonance Metal Organic Chemical Yfpor Deposition) system. The prepared $SnO_x$ thin films show generally over $90\%$ of optical transmittance at wavelength range of 380-780nm and about $1\times10^{-2\~3}ohm{\cdot}cm$ of electrical resistivity. In the present study, effects of $O_2/TMT\;and\;H_2/TMT$ mole ratio on the properties of $SnO_x$ films are investigated and the other process parameters such as microwave power, magnetic current power, substrate distance and working pressure are fixed. Based on our experimental results, the $SnO_x$ film composition ratio of Sn and O directly influences on the electrical and optical properties of the films prepared. The $SnO_x$ film with low electric resistivity and high transmittance could be obtained by controlling the process parameters such as $O_2/TMT\;and\;H_2/TMT$ mole ratio, which play an important role to change the composition ratio between Sn and O. An increase of $O_2/TMT$ mole ratio brought on the increases 0 content in the $SnO_x$ film. On the other hand, an increase of $H_2/TMT$ mole ratio lead to decreases the oxygen content in the film. The optimized composition ratio of oxygen : tin Is determined as 2.4: 1 at $O_2/TMT$ of 80 and $H_2/TMT$ of 40 mole ratio, respectively.

International Conference on Electroceramics 2005 (2005년도 국제 전자세라믹 학술회의)

  • 한국세라믹학회
    • Proceedings of the Korean Ceranic Society Conference
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    • 2005.06a
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    • pp.1-112
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    • 2005
  • This report is results of a research on recent R&D trends in electroceramics, mainly focusing on the papers submitted to the organizing committee of the International Conference on Electroceramics 2005 (ICE-2005) which was held at Seoul on 12-15 June 2005. About 380 electroceramics researchers attended at the ICE-2005 from 17 countries including Korea, presenting and discussing their recent results. Therefore, we can easily understand the recent research trends in the field of electroceramics by analyses of the subject and contents of the submitted papers. In addition to the analyses of the papers submitted to the ICE-2005, we also collected some informations about domestic and international research trends to help readers understand this report easily. We analysed the R&D trends on the basis of four main categories, that is, informatics electroceramics, energy and environment ceramics, processing and characterization of electroceramics, and emerging fields of electroceramics. Each main category has several sub-categories again. The informatics ceramics category includes integrated dielectrics and ferroelectrics, oxide and nitride semiconductors, photonic and optoelectronic devices, multilayer electronic ceramics and devices, microwave dielectrics and high frequency devices, and piezoelectric and MEMS applications. The energy and environment ceramics category has four sub-categories, that is, rechargable battery, hydrogen storage, fuel cells, and advanced energy conversion concepts. In the processing and characterization category, there exist domain, strain, and epitaxial dynamics and engineering sub-category, innovative processing and synthesis sub-category, nanostructured materials and nanotechnology sub- category, single crystal growth and characterization sub-category, theory and modeling sub-category. Nanocrystalline electroceramics, electroceramics for smart sensors, and bioceramics sub-categories are included to the emerging fields category. We hope that this report give an opportunity to understand the international research trend, not only to Korean ceramics researchers but also to science and technology policy researchers.

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Quality Evaluation of Juanbyeo as Aseptic-packaged Cooked Rice (무균포장밥 가공 적합품종 주안벼의 식미특성)

  • Oh, Sea-Kwan;Kim, Dae-Jung;Cheun, A-Reum;Yoon, Mi-Ra;Hong, Ha-Cheol;Choi, Im-Soo;Oh, Yea-Jin;Oh, Ki-Back;Kim, Yeon-Kyu
    • Korean Journal of Food Science and Technology
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    • v.42 no.6
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    • pp.721-726
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    • 2010
  • The objective of this study was to evaluate several varieties of aseptic-packaged cooked rice including Juanbyeo. Quality evaluations, such as by amylose, setback, toyo values and amylograms, were significantly higher in the Juanbyeo as compared to other samples. In addition, the Juanbyeo aseptic-packeged cooked rice showed significantly higher palatability characteristics and had a greater water absorption ratio than the other samples. For cold cooked rice, the relationship between palatability and texture was significantly high (p<0.01). Ilpumbyeo showed high scores for taste as a hot cooked rice, but as a cold cooked rice taste scores were lower than other samples. In the case of Juanbyeo cold cooked rice flavor was improved. When the Juanbyeo aseptic-packaged cooked rice was reheated in a microwave oven, it had better palatability than other varieties. Thus, the results of this study suggested that Juanbyeo can be effectively utilized as aseptic-packaged cooked rice.

A Study on Visual Identity of Korean Government (우리나라 행정부의 시각 정체성 연구)

  • Cho, Ju-Eun
    • Archives of design research
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    • v.19 no.2 s.64
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    • pp.261-272
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    • 2006
  • As we cannot think of our lives without a nation, it is closely related to almost every part of our daily lives. The role of government is becoming more important in the complex modern society as an essential element of national authority even though the government has indirect and secondary characteristics in its functional performance. Therefore, the government has to be efficient in planning and executing its policies, and it needs to be representative and fair as part of a national authoritative community. In the 21st century when symbolic and cultural importance of images are becoming more important, it is crucial for the government organizations to have an integrated identity design system that can satisfy both of these requirements of the government. However, the C.I.(Corporate Identity) of each Korean administrative branch has been developed separately and sporadically, which resulted in lack of consistency as part of the government. Shape and material of their C.I.s that follow short term design trend and popularity also lack uniqueness which can be distinguished from those of any private corporation. This may show that our government lacks systematic administrative capability, since image of a feature represents its characteristics and reality, and their recognition and evaluation from others become identity of the feature. In this perspective, the purpose of this thesis is to suggest an identity design system that has certain rules and regularity with wide variety of possible alterations for the central administration in Korea. In order to represent this visually, identity design system with both integrity and variety of possible alteration is created based on traditional Korean culture, especially the concept of Umyang-ohaeng and Samjae.

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A historical study on the flexibility square-format typeface and the prospects - Focused on the three-pairs fonts of hangeul - (탈네모글꼴에 관한 역사적 연구와 전망 - 세벌식 한글 글꼴을 중심으로 -)

  • Yu, Jeong-Mi
    • Archives of design research
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    • v.19 no.2 s.64
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    • pp.241-250
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    • 2006
  • Hangeul as the Korean unique characters were invented according to some character-making principles and based on scholars' exhaustive researches. While most of the characters in the world evolved naturally, Hangeul was invented based on a precise linguistic analysis of the time, and therefore, it is most scientific and reasonable among various characters throughout the world. Nevertheless, Hangeul typeface designs do not seem to inherit the ideology of scientific and reasonable Hangeul correctly. For the square forms have been used intact due to the influences from the Chinese characters which prevailed during the time. If a single set of square characters should be designed, as much as 11,172 fonts should be designed, which suggests that advantages of Mangeul may not well be used fully; Hangeul was invented to visualize every sound with the combinations of 28 vowels and consonants. Problems of such square fonts began to be identified since 1900's when typewriters were introduced first from the West. Since a typewriter is designed with 28 characters laid out on its keyboard by using such combinations, the letters may be easily combined on it. The so-called the flexibility square-format typeface was born as such. Specially, the three-pairs fonts of these can be combined up to 67 letters including vowels and consonants. The three-pairs fonts system can help to solve the problems arising form the conventional square fonts and inherit the original ideology of Hangeul invention. This study aims to review the history of the three-pairs fonts designs facilitated by mechanic encoding of Hangeul and thereupon, suggest some desirable directions for future Hangeul fonts. Since the flexibility square-format typeface is expected to evolve more and more owing to development of the digital technology, they would serve our age of information in terms of both functions and convenience. Just as Hunminjongum tried to be literally independent from the Chinese characters, so the flexibility square-format typeface designs would serve to recover identity of our Hangeul font designs.

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Establishment of Analytical Method for Methylmercury in Fish by Using HPLC-ICP/MS (고성능액체크로마토그래피-유도결합플라즈마 질량분석기를 이용한 어류 중 메틸수은 분석법 확립)

  • Yoo, Kyung-Yoal;Bahn, Kyeong-Nyeo;Kim, Eun-Jung;Kim, Yang-Sun;Myung, Jyong-Eun;Yoon, Hae-Seong;Kim, Mee-Hye
    • Korean Journal of Environmental Agriculture
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    • v.30 no.3
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    • pp.288-294
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    • 2011
  • BACKGROUND: Methylmercury is analyzed by HPLC-ICP/MS because of the simplicity for sample preparation and interference. However, most of the pre-treatment methods for methylmercury need a further pH adjustment of the extracted solution and removal of organic matter for HPLC. The purpose of this study was to establish a rapid and accurate analytical method for determination of methylmercury in fish by using HPLC-ICP/MS. METHOD AND RESULTS: We conducted an experiment for pre-treatment and instrument conditions and analytical method verification. Pre-treatment condition was established with aqueous 1% L-cysteine HCl and heated at $60^{\circ}C$ in microwave for 20 min. Methylmercury in $50{\mu}L$ of filtered extract was separated by a C18 column and aqueous 0.1% L-cysteine HCl + 0.1% L-cysteine mobile phase at $25^{\circ}C$. The presence of cysteine in mobile phase and sample solution was essential to eliminate adsorption, peak tailing and memory effect problems. Correlation coefficient($r^2$) for the linearity was 0.9998. The limits of detection and quantitation for this method were 0.15 and $0.45{\mu}g/kg$ respectively. CONCLUSION: Result for analytical method verification, accuracy and repeatability of the analytes were in good agreement with the certified reference materials values of methylmercury at a 95% confidence level. The advantage of the established method is that the extracted solution can be directly injected into the HPLC column without additional processes and the memory effect of mercury in the ICP-MS can be eliminated.

A Study on the Content of Minerals in Fortified Food (영양강화식품 중 무기질 함량 조사연구)

  • Kim, Myeong-Gil;Kim, Young-Sug;Kim, Young-Su;Lee, Seong-Bong;Ryu, Kyong-Shin;Yoon, Mi-Hye;Lee, Jong-Bok
    • Journal of Food Hygiene and Safety
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    • v.29 no.2
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    • pp.99-104
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    • 2014
  • This study was done to analyze the contents of minerals and to investigate the ratio of measured values to labeled values and to analyze the ratio of calcium to other minerals in 68 specimen with minerals - fortified commercial beverages, noodles, cereals and grain products. Content of calcium, iron and zinc in samples after microwave digestion was analyzed with an ICP-OES. The measured values of calcium were ranged 82.2~293.1% of the labeled values in 38 samples composed calcium - fortified commercial beverages, noodles, cereals and grain products. The measured values of iron and zinc were ranged 83.3~301.0%, 90.1~314.1% of the labeled values in minerals - fortified commercial beverages, noodles, cereals and grain products, 42, 24 samples. The Ca : Fe ratios were 90.55 (50.55~220.64) in fruit & vegetable juice, 850.41 in fruit & vegetable beverage, 553.49 in blended beverage, 179.07 (118.37~238.01) in soy milk, 204.39(41.64~397.52) in noodle, 296.97(121.64~868.88) in fried noodle, 30.89(15.69~62.05) in cereal and 7.73(0.22~49.92) in grain product. The Ca : P ratios were 1.44(0.96~1.98) in fruit & vegetable juice, 1.92 in fruit & vegetable beverage, 1.66 in blended beverage, 4.23(2.25~7.72) in soy milk, 1.14(0.28~1.97) in noodle, 1.88(1.17~2.42) in fried noodle, 1.29(0.87~2.92) in cereal and 0.30(0.06~1.57) in grain product. The Ca : Mg ratios were 1.85(0.87~5.04) in fruit & vegetable juice, 28.72 in fruit & vegetable beverage, 2.97 in blended beverage, 5.27(2.93~9.36) in soy milk, 3.97(1.34~7.57) in noodle, 6.77(4.63~10.78) in fried noodle, 4.40(2.30~12.55) in cereal and 1.17(0.23~7.48) in grain product. These results suggest calcium contents and the ratio of calcium contents to other minerals in calcium-fortified food products should be strictly controlled. Moreover, to avoid problems with Excessive nutrition, there must be initiatives for better understanding on food labelling and nutrition for fortified food.

Establishments of Lead Standards through Monitoring Heavy Metals in Calcium, Chitosan, and Propolis Health Foods (칼슘, 키토산, 프로폴리스 건강보조식품중 중금속 모니터링을 통한 납기준 제정)

  • Kim, Mee-Hye;Chung, So-Young;Sho, You-Sub;Kim, Myung-Chul;Kim, Chang-Min
    • Korean Journal of Food Science and Technology
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    • v.33 no.5
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    • pp.525-528
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    • 2001
  • This study was conducted to estimate the contents of heavy metals in some health foods available on Korean markets. The samples were digested with microwave system, then analyzed using GF-AAS for the contents of lead (Pb), cadmium (Cd) and arsenic (As). The contents of mercury (Hg) were determined using a mercury analyzer. The average values of Hg, Pb, Cd and As in calcium (Ca) health foods were 0.007, 1.08, 0.02 and 0.48 mg/kg respectively. Those values in chitosan health foods were 0.001, 0.36, 0.01 and 0.03 mg/kg respectively. Those values in propolis health foods were 0.013, 4.96, 0.01 and 0.13 mg/kg, respectively. The health foods that contained cow bone powders had the highest lead contents. Based on the variation in lead contents of those products, it could be possible that they might be contaminated through raw materials and/or manufacuring process. Some propolis products were also very high in lead contents. There could be risks for some population, especially the aged who overtake those health foods, to have heavy intake of lead. Therefore, we established the lead standards of 3.0, 2.0 and 5.0mg/kg less than for Ca, chitosan and propolis health foods respectively, based on the Codex method.

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