• Title/Summary/Keyword: Foreign Material

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Analysis of Regulation Standard and Radiological Characteristics of NORM Industry (국내·외 NORM 취급 산업 규제 기준 및 방사선학적 특성 분석)

  • Seung Beom Yoo;Ju Young Kim;Ga Eun Oh;Kwang Pyo Kim
    • Journal of Radiation Industry
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    • v.18 no.3
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    • pp.195-207
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    • 2024
  • International organizations such as IAEA and EC recommend graded approach by identifying NORM industries requiring radiation protection. In Korea, single regulation rather than graded regulation for NORM industry is applied. Therefore, it consumes more manpower and costs than necessary for both regulators and workers, and is not optimized. The purpose of this study is to analyze domestic and foreign NORM industry regulatory standards and radiological characteristics for graded approach of NORM industry in Korea. Safety reports and publications such as SRS 49 and ICRP 142 published by international organizations were investigated, and domestic and foreign NORM regulatory guidelines and legislation such as Health Canada and the Act on Protective Action Guidelines Against Radiation in the Natural Environment were investigated to indicate NORM industries and regulatory standards. The radioactivity concentration of raw materials or by-products, radiation dose by industrial process of the NORM industry identified in IAEA and Korea were investigated. Nine NORM industries in Korea were identified based on the NORM industry from IAEA and KINS survey report. Foreign countries such as Canada, UK and Denmark were executing graded approach such as classification of dose level or licensing, registration, notification based on safety assessment. Radioactivity concentration of domestic and foreign NORM industries were widespread up to 200 Bq g-1 or higher based on industrial process and work type, and numerous NORM industries that exceeded radiation dose of 1 mSv y-1 were indicated. Therefore, it is necessary to consider handling materials and work types of identified NORM industry when establishing graded approach for NORM industry in Korea considering domestic situation. The results of this study are expected to be used as basic data for developing methodology of graded approach for NORM industry in Korea.

Activation of Porcine Oocytes Following Intracytoplasmic Injection of Various Sperm Components and foreign species spermatozoa (여러 가지 정자구성성분 및 이종정자 주입에 의한 돼지난자의 활성)

  • Jun, S.H.;Shin, J.S.;Do, J.T.;Kwon, J.K.;Kim, N.H.;Lee, H.T.;Chung, K.S.
    • Clinical and Experimental Reproductive Medicine
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    • v.25 no.3
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    • pp.331-340
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    • 1998
  • We determined the incidence of activation, male pronuclear formation and apposition of pronuclei in porcine oocytes following intracy-toplasmic injection of various porcine sperm components and foreign species spermatozoa, such as mouse, human or cattle. The porcine oocytes were activated by injection of a spermatozoon or an isolated sperm head. Neither isolated sperm tail nor perinuclear material removed sperm head activated oocytes. Because injection of mouse, bovine or human spermatozoon activated porcine oocytes, the sperm born activation factors is not strict species specific. Male pronuclear formation and pronuclear apposition were observed in the porcine oocytes following injection of porcine, bovine, mouse or human spermatozoa. The electrical stimulation following sperm cell injection did not enhance the incidence of male pronuclear formation nor pronuclear apposition comparent with sperm cell injection alone (p>0.1). Mitosis and two cell division in some oocytes were observed at 20 to 24 h after injection of porcine spermatozoon. However, none of oocytes following injection of mouse, bovine or human spermatozoa developed to the mitotic metaphase or normally divided to the two cell stage. These results suggested that the oocyte activating factor(s) presented in the perinuclear material and it is not species specific for the porcine oocyte.

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A Study on the National Library's Collection Strategy and Utilization Plan through the Analysis of Online Material Collection Status of Major Libraries Abroad (해외 주요 도서관 온라인 자료 수집 현황 분석을 통한 국립중앙도서관의 수집 방향성 및 활용 방안 도출 연구)

  • Younghee Noh;Youngmi Jung;Aekyoung Son;Inho Chang;Kyung Sun Lee;Hyunju Cha
    • Journal of Korean Library and Information Science Society
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    • v.55 no.2
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    • pp.1-28
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    • 2024
  • This study aimed to present practical strategies for libraries in South Korea, including the National Central Library, to effectively respond to the new challenges of the digital era by systematically comparing and analyzing the status of online material collection and services of libraries both domestically and abroad. To achieve this, we sought to understand the cases and service status of online material collection in major foreign libraries and to derive directions and usage plans for our libraries based on the analysis of these foreign libraries' online material collection status. As a result of this research, it was found that the National Central Library needs to explore various strategies for expanding online material collection, including the proper collection and preservation of web resources that are being created and deleted, as well as expanding openness and utilizing archives. Secondly, as a central institution for future national information resources, it is necessary to establish a strategy for smoothly collecting, preserving, and servicing vast and complex web resources. Thirdly, there is a need to explore ways to implement a national-level web archive that can systematically collect, preserve, and utilize all web resources in our country. In the long term, it should be improved into a national platform capable of systematically collecting, preserving, and utilizing various types of web resources.

Resistance to Airflow of Grain as Affected by Grain Moisture Content (곡물(穀物)의 함수율(含水率) 변화(變化)에 따른 송풍저항(送風抵抗)에 관(關)한 연구(硏究))

  • Kim, M.S.;Kim, S.R.
    • Journal of Biosystems Engineering
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    • v.11 no.2
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    • pp.55-65
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    • 1986
  • The resistance to the passage of airflow through various agricultural products is an important consideration in the design of an aeration or drying system. The amount of resistance to airflow varied widely from one kind of grain to another, and depended upon airflow rate, surface texture and shape of the particles, the size and configuration of voids, and foreign and fine material in the grain bed. The airflow rate was the major factor considered on this kind of study in the early stages. But these days, the studies on the resistance to airflow of grain affected by grain moisture content and foreign and fine material have been widely carried out. However the foreign an fine material in the grain bed could not be a major factor on the study in Korea because there were only a few grain process procedure after harvesting it. The objectives of this study were to investigate the effect of moisture content and airflow rate on airflow resistance to grain, and to develop a model to predict the static pressure drop across the grain bed as a function of moisture content and airflow rate. The rough rice varieties, Akibare, Milyang 15 (Japonica types), Samkwang, Backyang (Indica types)and covered barley variety, Olbori, which were harvested in 1985 were used in the experiment after cleaning them. Resistances to airflow of grain were investigated at four levels of moisture content (13-25%, wb.) for ten different airflow rates($0.01-0.15m^3/sm^2$). The results of this study are summarized as follows; 1. Theaverage bulk densities were $585.3kg/m^3$ for rough rice and $691.6kg/m^3$ for barley at the loose fill, and were $648.8kg/m^3$ for rough rice and $758.2kg/m^3$ for barley at the packed fill. The pressure drops at the packed fill beds were approximately 1.4 to 1.8 times higher than those at the loose fill beds. 2. The pressure drops across grain beds deceased with the increase of moisture content and increased with airflow rate. The decreasing rates of pressure drop across grain beds according to the moisture contents at the lower airflow rates were higher than those at the higher airflow rates, and the increasing rates of pressure drop according to the airflow rates at the lower moisture contents were higher those at higher moisture contents. 3. The pressure drop across barley bed were much higher than rough rice beds and the pressure drops across Japonica type rough rice beds were a little higher than Indica type. 4. The mathematical models to predict the pressure drop across grain beds as a function of moisture content and airflow rate were developed from these experiments.

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Drag Torque Prediction for Automotive Wheel Bearing Seals Considering Viscoelastic as Well as Hyperelastic Material Properties (초탄성 및 점탄성 물성을 고려한 자동차용 휠 베어링 실의 드래그 토크 예측)

  • Lee, Seungpyo
    • Tribology and Lubricants
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    • v.35 no.5
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    • pp.267-273
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    • 2019
  • Wheel bearings are important automotive parts that bear the vehicle weight and translate rotation motion; in addition, their seals are components that prevent grease leakage and foreign material from entering from the outside of the bearings. Recently, as the need for electric vehicles and eco-friendly vehicles has been emerging, the reduction in fuel consumption and $CO_2$ emissions are becoming the most important issues for automobile manufacturers. In the case of wheel bearings, seals are a key part of drag torque. In this study, we investigate the prediction of the drag torque taking into consideration the hyperelastic and viscoelastic material properties of automotive wheel bearing seals. Numerical analysis based on the finite element method is conducted for the deformation analyses of the seals. To improve the reliability of the rubber seal analysis, three types of rubber material properties are considered, and analysis is conducted using the hyperelastic material properties. Viscoelastic material property tests are also conducted. Deformation analysis considering the hyperelastic and viscoelastic material properties is performed, and the effects of the viscoelastic material properties are compared with the results obtained by the consideration of the hyperelastic material properties. As a result of these analyses, the drag torque is 0.29 Nm when the hyperelastic characteristics are taken into account, and the drag torque is 0.27 Nm when both the hyperelastic and viscoelastic characteristics are taken into account. Therefore, it is determined that the analysis considering both hyperelastic and viscoelastic characteristics must be performed because of its reliability in predicting the drag torque of the rubber seals.

Production & Performance Assessment of Composite Material Flexible Propeller (복합재료 유연 프로펠러의 제작 및 성능 평가)

  • Lee, Sang-Gab;Byun, Joon-Hyung;Paik, Bu-Geun;Hyun, Beom-Soo
    • Journal of the Society of Naval Architects of Korea
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    • v.46 no.6
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    • pp.667-674
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    • 2009
  • The researches on the development of composite material underwater vehicle propeller have been actively attempted for the reduction of radiation noise with outstanding damping effects. Composite material propellers have almost been designed and produced by the foreign experts, and it is difficult to obtain the related informations about their flow, vibration, material characteristics because they are treated as the secrets with close relationship to the military technology, especially in the case of underwater vehicles. For the security of domestic manufacture of composite material propeller and the comparison and examination of its performance and radiation noise characteristics with those of German CONTUR composite material propeller, two propellers were self-produced according to the fiber weaving and array using compressible molding process and their self performances and radiation noise characteristics were measured. The mean fluctuations of blade tip of self-produced composite material propeller were increased and the radiation noises in the low frequency band were reduced compared to those of CONTUR, which could be estimated as the change of material characteristics and also be thought to be used for the future research informations.

A Fundamental Study on Effective Width Evaluation of Laminated Composite Box Girder (복합적층 박스거더의 유효폭 산정을 위한 기초연구)

  • Chun, Kyoung-Sik;Ji, Hyo-Seon;Park, Won-Tae
    • Journal of the Korean Society for Advanced Composite Structures
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    • v.6 no.3
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    • pp.26-31
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    • 2015
  • The domestic and foreign specifications presented the effective width based on flange length to width ratio only. The existing paper on the effective width grasped of the effect of span, load type and cross-section properties, but localized steel bridges. Recently, The studies are going on in progress for the application of fiber reinforced composite material in construction field. Therefore, it is required to optimum design that have a good grasp the deformation characteristic of the displacements and stresses distribution and predict variation of the effective width for serviceability loading. This research addresses the effective width of all composite material box girder bridges using the finite element method. The characteristics of the effective width of composite structures may vary according to several causes, e.g., change of fibers, aspect, etc. Parametric studies were conducted to determine the effective width on the stress elastic analysis of all composite materials box bridges, with interesting observations. The various results through numerical analysis will present an important document for construct all composite material bridges.

Characteristics in the Lingerie Looks Designed by John Galliano (John Galliano 작품에 나타난 란제리룩의 특성)

  • Kim, Sun Young
    • Journal of the Korean Home Economics Association
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    • v.51 no.2
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    • pp.147-159
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    • 2013
  • This study aims at developing and producing the creative design of a lingerie look after reviewing the aesthetic value about lingerie look featured in John Galliano's works. As for the research method, the selection process from the works was followed together with literature review for empirical analysis over lingerie looks, where 2,764 pieces in total were reviewed from Galliano's Pret-a-Porter collections covering from 2001S/S until 2010F/W and Christian Dior's Haute Couture and Pret-a-Porter collections that he is in charge of as head designer and 291 pieces were finally singled out that show the lingerie look image well. Then, the formative expression was examined about those looks and the characteristics were induced from them. Formativeness expressed in Galliano's lingerie look, in term of lingerie style, was categorized as erotic, retro, and deconstructive. The glittering and smooth material like silk and satin, and the visible material like lace and chiffon were mainly used for material rather than foreign material. By doing so, the romantic and erotic image was highlighted. In the production method, it was grouped into transposition of wear, direct and indirect exposition, and deconstructive way. These aesthetic characteristics introduced by formative expression appeared in the form of eroticism, play, and deconstructiveness.

Evaluating methods of properties in composite insulators and necessities (Composite insulator의 특성평가 방향 및 필요성)

  • Kim, I.S.;Cho, H.G.;Kang, D.P.
    • Proceedings of the KIEE Conference
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    • 1995.07c
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    • pp.1226-1228
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    • 1995
  • This paper introduced foreign standard testing methods on composite insulators(for transmission, distribution) and mentioned on (1)evaluation of material property (2)short-term test of prototype (3)insulation efficiency on use to evaluation property of insulators made of composite insulating materials.

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A Study on pronunciationi in Scientific Names of Landscape Plants (조경직물 학명의 발음에 관한 연구)

    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.1
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    • pp.44-50
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    • 1998
  • The purpose of this paper is to analyzed of pronunciationi of botanical names of landscape plants. This study includes the plant that are possible to use as woody landscape material as well as both the native and foreign plants that are already used. Botanical name must be divided into syllables. Every latin word has as many syllables as it has separate vowels or diphthongs. The last syllables is never accentd. The next to the last syllables is called the penult, the third from the last syllables is called the antepenult. The pronuciationi of latinized commemorative names is here that the rules are most apt to be disregarded or ignored.

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