• Journal of Korean Society for Atmospheric Environment
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• v.32 no.3
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• pp.320-328
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• 2016

Among biogenic volatile organic compounds (BVOCs) in the natural ecosystem, monoterpenes, along with isoprene, play important roles in atmospheric chemistry and make significant impacts on air pollution and climate change, especially due to their contribution to secondary organic aerosol production and photochemical ozone formation. It is essential to measure monoterpene concentrations accurately for understanding their oxidation processes, emission processes and estimation, and interactions between biosphere and atmosphere. Thus, traceable calibration standards are crucial for the accurate measurement of monoterpenes at ambient levels. However, there are limited information about developing calibrations standards for monoterpenes in pressured cylinders. This study describes about developing primary standard gas mixtures (PSMs) for monoterpenes at about 2 nmol/mol, near ambient levels. The micro-gravimetric method was applied to prepare monoterpene (${\alpha}$-pinene, 3-carene, R-(+)-limonene, 1,8-cineole) PSMs at $10{\mu}mol/mol$ and then the PSMs were further diluted to 2 nmol/mol level. To select an optimal cylinder for the development of monoterpene PSMs, three different kinds of cylinders were used for the preparation and were evaluated for uncertainty sources including long-term stability. Results showed that aluminum cylinders with a special internal surface treatment (Experis) had little adsorption loss on the cylinder internal surface and good long-term stability compared to two other cylinder types with no treatment and a special treatment (Aculife). Results from uncertainty estimation suggested that monoterpene PSMs can be prepared in pressured cylinders with a special treatment (Experis) at 2 nmol/mol level with an uncertainty of less than 4%.

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.815-819
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• 2013

Micropatterns of streptavidin and human epidermal carcinoma A431 cells were successfully imaged, as received and without any labeling, using cluster $Au_3{^+}$ ion beam-based time-of-flight secondary ion mass spectrometry (TOF-SIMS) together with a principal component analysis (PCA). Three different analysis ion beams ($Ga^+$, $Au^+$ and $Au_3{^+}$) were compared to obtain label-free TOF-SIMS chemical images of micropatterns of streptavidin, which were subsequently used for generating cell patterns. The image of the total positive ions obtained by the $Au_3{^+}$ primary ion beam corresponded to the actual image of micropatterns of streptavidin, whereas the total positive-ion images by $Ga^+$ or $Au^+$ primary ion beams did not. A PCA of the TOF-SIMS spectra was initially performed to identify characteristic secondary ions of streptavidin. Chemical images of each characteristic ion were reconstructed from the raw data and used in the second PCA run, which resulted in a contrasted - and corrected - image of the micropatterns of streptavidin by the $Ga^+$ and $Au^+$ ion beams. The findings herein suggest that using cluster-ion analysis beams and multivariate data analysis for TOF-SIMS chemical imaging would be an effectual method for producing label-free chemical images of micropatterns of biomolecules, including proteins and cells.

• Journal of the Korean Chemical Society
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• v.42 no.4
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• pp.432-442
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• 1998

Since the definition of pH, $pH=-Ioga_H$ is based on a single ion activity, pH values can not be determined with measurement itself, but require an approximation method. They are derived from EMF measurement of a liquid junction free cell using hydrogen and Ag/AgCl electrodes. Primary standard materials with certified pH values can be obtained with this approximation method. Standard buffer solutions are used to calibrate pH meters. Thus the accuracy of the pH values of standard buffer solutions limits the reliability of measured pH values can be obtained with this approximation method. Standard buffer solution are used to calibrate pH meters. Thus the accuracy of the pH values of standard buffer solutions limits the reliability of measured pH values of sample solutions. To certify the pH values, we have established the system for the primary standard measurement and certified the pH of buffer solutions in the range of 1.6∼12.5 pH unit within uncertainty of ${\pm}0.005$ pH unit.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.423-431
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• 2020

This study examines the cost and benefit (i.e., income) of the Forest Stewardship Council (FSC) rubber plantations in Thailand. The study attempts to identify the challenges to the implementation of FSC standards in rubber plantations in the country. A total of 60 rubber farmers in two Southern provinces, namely, Songkhla and Rayong, were interviewed through a standardized questionnaire to gather primary data. The study found that small-, medium- and large-sized FSC rubber plantations were worth investing in. All sizes of rubber plantations had similar values of benefit cost ratio (BCR). It was also found that the values of the discount payback period (DPP) of the three forms of FSC rubber plantations were 9-12 years, while the large rubber plantations had the highest internal rate of return (IRR) (19.0%). It implies that the large-size plantations had the highest values. The rubber farmers in the study area reported that they are facing a number of problems and hardships in implementing FSC standards, lacking knowledge and understanding of FSC, especially for preparing documentation. Therefore, the Thai government should take proper policy initiatives to remove all the problems and barriers in implementing FSC standards for the sustainable rubber production in the country.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.9
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• pp.989-996
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• 2009

RF and microwave power is a basic quantity in electromagnetic metrology which linked directly to major electro-magnetic quantities such as attenuation, RF voltage, antenna characteristics and field strength. This paper deals with a power meter and power sensor with associated theory for RF and microwave power measurement. We study the theory and the key aspects in design of a 3.5 mm coaxial microcalorimeter which works from 50 MHz to 26.5 GHz as a primary microwave power standard.

• The Korean Journal of Archival Studies
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• no.1
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• pp.7-22
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• 2000

It is almost impossible to fulfill the users' information needs efficiently without any finding aids. The idiosyncrasy of archival materials had led the archivists to develop their own descriptive rules until the mid of 1980s. It was the arrival of computers and information networks that stimulated the archival community to standardize its variant descriptive practices. The primary purpose of the national and international archival description standards is to facilitate the cooperative archival data exchange. The Ad Hoc Commission on Descriptive Standards of the International Council on Archives adopted ISAD(G) and ISAAR(CPF) in 1993 and in 1995 respectively. ISAD(G) guides the formulation of information in each of 26 elements that may be combined to constitute the description of an archival entity. ISAAR(CPF) is to give general rules for the establishment of archival authority records in descriptions of archival documents. Histories, structures and fundamental principles of those two international archival standards have been studies in this article. Most of the present archival description standards are based on the principle of provenance and the authority model. The instability of modern organizations and the digitalization of record keeping systems have been making the archivists to review these basic archival principles. It is suggested that Korean archival community should attempt to draft a national archival descriptive standard suitable to the Korean archival practice and Korean language in the framework of the international standards.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.99-99
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• 2011

Fuel cell systems are a completely different form of electricity source that has been used so far and is an aggregation of multiple technologies with multidisciplinary features that can be operated safely only when gas and electrical safety are being considered. Since fuel cells generate through electrochemical reactions there are difficulties in ensuring electricity safety, power quality assessment, effective control and reliability standards for system faults using conventional inspection techniques and even though they are necessary as a primary means for reduction of CO2 owing to the Climate Convention, electrical safety assessment and measures are required for the prevention of faults in residential facilities. Although small-scaled distributed power supplies can be utilized as important means of peak control and energy management measures, research is required for observing the effects on the system and the development of inspection technology to ensure stable operation, and the electrical safety of residential fuel cell systems need to be assessed and the problems derived for establishing electrical safety standards. From the year 2002, Japan has established laws on technical safety standards and development and rules on the product specifications and standards for the industrialization of hydrogen fuel cells. Also, a lot of effort have been made for the commercialization of fuel cells by building one-stop certification services. Internationally, the IEC TC 105 has established international standards based on fuel cells. In order to protect the national interest, the country should be able to respond accordingly meet global standards. In fact, in Korea, to comply with the international trend, Korea Energy Management Corporation is establishing a certified agenda for fuel cells and Korean Agency for Technology and Standards is enacting technical standards for fuel cells. The current terms of fuel cells are that research has been focused more on the quality and performance of manufactured products rather than stable power operation and maintenance over time. In this paper, by considering the household fuel cell as a power device, the safety standards of the fuel cell system for a reliable operation with the existing power system is being proposed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.1
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• pp.67-79
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• 1996

This paper presents a composite luminance signal processing system for NTSC, PAL and SECAM standards. Eaxh of the three standards employs its own specifications of subcarmier bandwidth and luminance signal waveform. The proposed system, compatible to the specifications of the three standard and B/W TV, implements variable freqneucy characteristics by controlling filter coefficients. The major features of the system are a luminance/chroma separation unit and an aperture compensation unit. The luminance/chroma separation unit employes a notch filter selection a trap freqneyc to atenuate unwanted color signals in luminance signal bands. The aperture compensation unit comprises two subunits, to provide clear color definition for each of the three standards: a primary compensation circuit and a variable compensation circuits. The proposed system yields a 40 dB gain from the chroma/luminance separation and a 10 dB gain from the aperture compensation unit.

• Journal of electromagnetic engineering and science
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• v.16 no.4
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• pp.225-228
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• 2016

KRISS-V, a V-band millimeter-wave source module for a primary RF power standard and calibration system developed by the Korea Research Institute of Standards and Science is here presented. The output power of KRISS-V is several times higher than that of commercial amplifier/multiplier chains and is highly stable (the standard deviations of output power are less than 0.01% in the worst case). The spectral purity of KRISS-V is high enough to consider it a single-tone signal generator. We also added programmable attenuation capability to KRISS-V for remote power control. Moreover, the in-house source module is cost-effective and adaptable to various measurement schemes. The structure of the model as well as detailed component information are introduced so that it can be reproduced.

• Proceedings of the CALSEC Conference
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• 2001.08a
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• pp.141-154
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• 2001

This paper presents a fundamental study to establish a standardization system of the Construction Continuous Acquisition and Life-cycle Support(CALS). States of standardization in the Construction CALS were reviewed to find some defects in developing CALS system in construction industry. It is analyzed that three of major parts were needed to put up a standardization system for the Construction CALS. Firstly, the range of Construction CALS standardization is set up by identifying of Construction CALS and defining the standard and standardization. Secondly, the strategy to enable more effective implementation of Construction CALS standardization and the relationship of the concerned system presented can be used for establishing the Construction CALS standardization system. In addition, the spread and application device is proposed for using Construction CALS standards at public institutions and construction related companies. Conclusively, a classification system of the Construction CALS standards was proposed and some objects to be standardized were presented in the classification system. What were studied in this paper will provide the primary information and guidance to develop a guideline for standardization of the Construction CALS.