• Title, Summary, Keyword: CEN method

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Introduction to European Standard Methods for Physical and Chemical Analysis of Horticultural Substrates (원예용 배지의 물리·화학성 분석을 위한 유럽의 표준방법)

  • Kim, Kye-Hoon;Kang, Ji-Young
    • Horticultural Science & Technology
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    • v.19 no.2
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    • pp.179-185
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    • 2001
  • Throughout the world, physical and chemical analyses of horticultural substrates are carried out in many different ways at the different laboratories. In Europe, standardization in properties and analytical methods of horticultural substrates has been a topic over the last decades. As a result, the CEN methods as European standard methods for the physical and chemical analyses were introduced and the final draft was reported in 1999 by CEN(Committee for European Standardization). Dry matter and moisture content are analyzed after drying samples at $103^{\circ}C$. Laboratory compacted bulk density is analyzed by determining the weight of sample compacted in the test cylinder with constant volume. Dry bulk density, particle density, total pore space, water volume, air volume and volume shrinkage are determined by saturating, draining and drying the sample using double rings and a sand suction table. pH and EC are analyzed by 1:5(sample:distilled water) extraction method on the basis of volume. Organic matter and ash content are determined after drying and combusting the samples. Now, CEN methods are being regarded almost as European standard methods. Further study needs to be carried out for universal applicability of the CEN methods to all the substrates.

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Comparison Study on Efficacies of Disinfectants and Sanitizers Among Methods for Quantitative Surface Test (살균소독제의 정량적 표면시험방법별 유효성 비교)

  • Kim, Ae-Young;Kim, Yong-Su;Ha, Sang-Do
    • Journal of Food Hygiene and Safety
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    • v.25 no.3
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    • pp.238-244
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    • 2010
  • Currently, in vitro suspension tests using tubes are used as a authorized test method for sanitizers and disinfectants. However, the methods could not accurately assess the efficacy of sanitizers and disinfectant on the food-contacted surfaces in the field. This study evaluated the effectiveness of 5 kinds of representative sanitizers and disinfectants against E. coli and S. aureus to compare three quantitative surface testing methods that have been internationally standardized. As a result, the ASTM E2111-05 (ASTM(1)) test method obtained 5.18 $\pm$ 0.03 and 5.27 $\pm$ 0.04 log cfu/carrier reduction in dealing with E. coli and S. aureus, respectively, the ASTM E2197-02 (ASTM(2)) test method obtained 4.63 $\pm$ 0.04 and 3.97 $\pm$ 0.03 log cfu/carrier reduction and the CEN EN 13697 test method should 6.14 $\pm$ 0.05 and 5.31 $\pm$ 0.10 log cfu/carrier reduction in clean condition (CEN(1)) but 4.37 $\pm$ 0.02 and 4.06 $\pm$ 0.01 log cfu/carrier reduction in dirty condition (CEN(2)). Among them, CEN(1) showed the highest bactericidal effects, whereas ASTM(2) and CEN(2) revealed low performance (p < 0.05). In conclusion, the bactericidal effects of the ASTM(2) method and the CEN EN 13697 method adopting stainless steel were lower than the ASTM(1) method, which uses glass. The effectiveness assessment results among nationally accredited test methods were different each other. This implies that they could not fit for in the accurate evaluation of sanitization and disinfection on food-contact surfaces in practical food-processing fields. These results could be used as a basic data for establishment of an official surface test methods applicable in the field.

Projected Workforce of Certified Emergency Nurses in Korea (응급전문간호사 인력 수요추계에 관한 조사연구)

  • Kim, Il-Ok;Oh, Pok-Ja
    • Korean Journal of Adult Nursing
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    • v.15 no.4
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    • pp.542-550
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    • 2003
  • Purpose: The purpose of this study was to suggest the projected workforce of certified emergency nurses in Korea. Method: The methods used in this study are 1) demand & ratio model was used for the projected workforce of CEN, 2) Index functional formula was used for the suggestion of the number of general hospitals and hospitals, 3) Experts in Emergency care were contacted to get an opinion and information about the criteria of distribution and scope of CEN, 4) National and international internet data were collected. Result: The demand of CEN were analyzed by two ways; demand of Emergency centers only and demand of emergency centers including community centers. The number of CENs needed to meet the demands in 2002, 2005 and 2010 was estimated at minimum of 1,512 to maximum1,576, 1,640 to 1,704 and 1,892 to 1,956 respectively. The projected number of CENs for the 2002 was 1% total available nurses in Korea, and 3.2 CENs per 100,000 population. Conclusion: It is really desirable that CENs not only work for hospital emergency centers but also for emergency related centers in community.

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The conversion of ammonium uranate prepared via sol-gel synthesis into uranium oxides

  • Schreinemachers, Christian;Leinders, Gregory;Modolo, Giuseppe;Verwerft, Marc;Binnemans, Koen;Cardinaels, Thomas
    • Nuclear Engineering and Technology
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    • v.52 no.5
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    • pp.1013-1021
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    • 2020
  • A combination of simultaneous thermal analysis, evolved gas analysis and non-ambient XRD techniques was used to characterise and investigate the conversion reactions of ammonium uranates into uranium oxides. Two solid phases of the ternary system NH3 - UO3 - H2O were synthesised under specified conditions. Microspheres prepared by the sol-gel method via internal gelation were identified as 3UO3·2NH3·4H2O, whereas the product of a typical ammonium diuranate precipitation reaction was associated to the composition 3UO3·NH3·5H2O. The thermal decomposition profile of both compounds in air feature distinct reaction steps towards the conversion to U3O8, owing to the successive release of water and ammonia molecules. Both compounds are converted into α-U3O8 above 550 ℃, but the crystallographic transition occurs differently. In compound 3UO3·NH3·5H2O (ADU) the transformation occurs via the crystalline β-UO3 phase, whereas in compound 3UO3·2NH3·4H2O (microspheres) an amorphous UO3 intermediate was observed. The new insights obtained on these uranate systems improve the information base for designing and synthesising minor actinide-containing target materials in future applications.

Compressive Behavior of Concrete with Loading and Heating (가열 및 재하에 의한 콘크리트의 압축거동)

  • Kim, Gyu-Yong;Jung, Sang-Hwa;Lee, Tae-Gyu;Kim, Young-Sun;Nam, Jeong-Soo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.14 no.4
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    • pp.119-125
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    • 2010
  • The performance deformation of concrete can be caused by many factors such as load, thermal strain and creep at high temperature. Japan, Europe and America have been doing various experimental studies to solve these problems about thermal properties of concrete at high temperature, each study has generated different results due to a heating methods, heating hours, size of specimens and performance of a the loading, heating method, size of specimen and heating machine. There has been no unified experimental method so far. Therefore, this study reviewed experimental studies on the strength performance of concrete subject to heating and loading method. As a result, compressive strength of specimen prestressed increase in the temperature range of between $100^{\circ}C$ and about $400^{\circ}C$. Also, results can be analyzed as compare equation of compressive strength at elevated temperature with CEN and CEB code.

Fundamental Study on Evaluation method of Activity Factor of Fly Ash (플라이애시의 활성도지수 평가에 관한 기초적 연구)

  • Park, Sang-Joon
    • Journal of the Korea Institute of Building Construction
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    • v.8 no.5
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    • pp.59-65
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    • 2008
  • In the evaluation method of KS on the activity factor of fly ash, same amount of cement should be replaced with fly ash. Therefore, contradictory effects on concrete strength exist, i. e. strength decease due to low content of cement and strength increase of strength due to filling-pore-function of fly ash. European Committee for Standardization (CEN) specifies the method 1 to 4. adding fly ash without reducing the content of cement, for the evaluation method on activity factor of fly ash. This study investigates the applicability of the method 2 of CEN to mix design of concrete. The followings are derived ; There is a key ratio of f)y ash mixing which enhances the incremental ratio of mixing water to improve fluidity of mortar. The incremental ratio of mixing water is maximized about 11% ratio of fly ash mixing. Compressive strength most slightly increases at that ratio of fly ash mixing. Activity factor of fly ash increases as water-cement ratio becomes low and contents of fly ash becomes high. Moreover, quality of fly ash and condition of mix design affect the applicable amount of fly ash and available range of water-cement ratio. However, this method has some problems for practical purpose because activity factors of fly ash for some cases are over 1.0. Further research should be conducted to develop more useful method of evaluating activity factor of fly ash.

Block Sparse Low-rank Matrix Decomposition based Visual Defect Inspection of Rail Track Surfaces

  • Zhang, Linna;Chen, Shiming;Cen, Yigang;Cen, Yi;Wang, Hengyou;Zeng, Ming
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.12
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    • pp.6043-6062
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    • 2019
  • Low-rank matrix decomposition has shown its capability in many applications such as image in-painting, de-noising, background reconstruction and defect detection etc. In this paper, we consider the texture background of rail track images and the sparse foreground of the defects to construct a low-rank matrix decomposition model with block sparsity for defect inspection of rail tracks, which jointly minimizes the nuclear norm and the 2-1 norm. Similar to ADM, an alternative method is proposed in this study to solve the optimization problem. After image decomposition, the defect areas in the resulting low-rank image will form dark stripes that horizontally cross the entire image, indicating the preciselocations of the defects. Finally, a two-stage defect extraction method is proposed to locate the defect areas. The experimental results of the two datasets show that our algorithm achieved better performance compared with other methods.

Optimum Condition of the Coir-Based Substrate for Growth of Red Pepper (Capsicum annuum L.) Plug Seedlings (코이어 혼합상토를 이용한 고추 육묘용 최적 상토개발)

  • Lee, Hyun-Haeng;Ha, Sang-Keon;Kim, Kye-Hoon
    • Korean Journal of Soil Science and Fertilizer
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    • v.40 no.5
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    • pp.369-376
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    • 2007
  • This experiment was carried out to investigate optimum conditions of coir-based substrates for the red pepper plug seedlings. Eleven different coir based substrates prepared by mixing of coir, vermiculite, rice hull, perlite, zeolite, mixed at different ratios were tested. The physical and chemical properties of the substrates were analyzed by the CEN (European committee for standardization) method. Fresh and dry weights of shoot and root, leaf area, root length, and T/R ratio (dry shoot weight/dry root weight) were determined at 55 days after sowing. The results showed that the growing media CRZ 8(coir:rice hull: vermiculite=8:1.9:0.1) and CVSZ 6(coir:silver vermiculite: zeolite=6:3.9:0.1) can successfully be used for pepper plug seedlings judging from dry weight and T/R ratio of the plug seedlings. The optimal range of total pore space, water volume, air volume, easily available water content and water buffering capacity of the coir-based growing substrates for pepper plug seedlings were in the range of 92~94%, 52~60%, 32~43%, 18~21%, and 0.9~8%, respectively.