• Journal of Electrical Engineering and Technology
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• v.1 no.3
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• pp.359-365
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• 2006

Since the start of the KSTAR (Korea Superconducting Tokamak Advanced Research) project, Instrumentation and Control (I&C) of the Neutral Beam Test Facility (NB-TF) has been striving to answer diverse requests arising from various facets during the project's development and construction phases. Hard-wired electrical circuits have been designed, tested, fabricated, and finally installed to the relevant parts of the system. In relation to the vacuum system I&C, controlling functions for the rotary pumps, a Roots pump, two turbomolecular pumps, and four cryosorption pumps have been constructed. I&C for the ion source operation are the temperature and flow rate signal monitoring, Langmuir probe signal measurements, gradient grid current measurements, and arc detector circuit. For the huge power system to be monitored or safely operated, many temperature measurement functions have also been implemented for the beam line components like the neutralizer, bending magnet, ion dump, and calorimeter. Nearly all of the control and probe signals between the NB test stand and the control room were made to be transmitted through the optical cables. Failures of coolant flow or beam line vacuum pressure were made to be safely blocked from influencing the system by an appropriate interlock circuit that will shut down the extraction voltage application to the system or prevent damages to the vacuum components. Preliminary estimation of the beam power through the calorimetric measurement shows that 87.9% of the total power of the 60kV/18A beam with 200 seconds duration is absorbed by the calorimeter surface. Most of these I&C results would be highly appropriate for the construction of the main NBI facility for the KSTAR national fusion research project.

• Tribology and Lubricants
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• v.15 no.3
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• pp.265-271
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• 1999

Wherever there are rotating equipment and contact between surface, there is wear and the generation of wear particles. The particles contained in the lubricating oil carry detailed and important information about the condition monitoring of the machine. This information may be deduced from particle shape, composition, size distribution, and concentration. Therefore, This paper was undertaken to Ferrography system of wear debris generated from lubricated moving machine surface. The lubricating wear test was performed under different experimental conditions using the Falex wear test of Pin and V-Block type by Ti(C, N) coated. It was shown from the test results that wear particle concentration (WPC) and wear severity Index( $I_{S}$), size distribution in normal and abnormal wear have come out all the higher value by increases sliding friction time. Wear shape is observed on the Ferrogram it was discovered a thin leaf wear debris as well as ball and plate type wear particles. This kind of large wear shape have an important effect not only metals damage, but also seizure phenomenon.

• Parasites, Hosts and Diseases
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• v.58 no.1
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• pp.99-102
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• 2020

Two-point mutations (V419L and L925I) on the voltage-sensitive sodium channel of bed bugs (Cimex lectularius) are known to confer pyrethroid resistance. To determine the status of pyrethroid resistance in bed bugs in Korea, resistance allele frequencies of bed bug strains collected from several US military installations in Korea and Mokpo, Jeollanamdo, from 2009-2019 were monitored using a quantitative sequencing. Most bed bugs were determined to have both of the point mutations except a few specimens, collected in 2009, 2012 and 2014, having only a single point mutation (L925I). No susceptible allele was observed in any of the bed bugs examined, suggesting that pyrethroid resistance in bed bug populations in Korea has reached a serious level. Large scale monitoring is required to increase our knowledge on the distribution and prevalence of pyrethroid resistance in bed bug populations in Korea. Based on present study, it is urgent to restrict the use of pyrethroids and to introduce effective alternative insecticides. A nation-wide monitoring program to determine the pyrethroid resistance level in bed bugs and to select alternative insecticides should be implemented.

• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2349-2355
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• 2023

In the TRITIUM project, an on-site monitoring system is being developed to measure tritium (³H) levels in water near nuclear power plants. The quite low-energy betas emitted by ³H have a very short average path in water (5 ㎛ as shown by simulations for 18 keV electrons). This path would be further reduced by impurities present in the water, resulting in a significant reduction of the detection efficiency. Therefore, one of the essential requirements of the project is the elimination of these impurities through a filtration process and the removal of salts in solution. This paper describes a water treatment system developed for the project that meets the following requirements: the water produced should be of near-pure water quality according to ISO 3696 grade 3 standard (conductivity < 10 µS/cm); the system should operate autonomously and be remotely monitored.

• Journal of Pharmaceutical Investigation
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• v.39 no.5
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• pp.367-372
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• 2009

A rapid liquid chromatography/tandem mass spectrometry (LC/MS/MS) assay method was developed for the determination of topotecan levels in rat serum. The assay utilized a single liquid-liquid extraction with a mixture of ethy l acetate and acetonitrile (6:1 v/v) and isocratic elution. The multiple reaction monitoring was based on the transition of m/z 422.0$\rightarrow$376.5 for topotecan and 315.1$\rightarrow$226.6 for clomipramine (internal standard). The developed assay was validated to demonstrate the specificity, recovery, lower limit of quantification (LLOQ), accuracy and precision. The assay was linear over a concentration range from 0.5-100 ng/mL, with LLOQ being 0.5 ng/mL using a small volume of rat serum (0.1 mL). The mean intra- and inter-day assay accuracy was 87.7-111.0% and 97.8-108.3, respectively, and the mean intra- and interday precision was between 1.6-4.3% and 3.8-10.3, respectively. The developed assay was applied to a pharmacokinetic study after a bolus i.v. injection of topotecan in rats.

• Corrosion Science and Technology
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• v.16 no.4
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• pp.161-166
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• 2017

The qualitative composition of active components of the corrosion inhibitor CGW-85567 was studied. It was found that С18:2 and С18:1 imidazolines and the corresponding imidazolin-amides are the major components. The HPLC/MS technique was developed for their determination in the water solutions of monoethylene glycol (MEG). Industrial application of the inhibitor showed that MEG solution retained high concentration of the inhibitor for a long time after ceasing its addition into pipelines. Low values of the partition coefficients (0.010-0.014) of imidazolines in the system "water solution of MEG (concentration of MEG 62-85% v/v) - gas condensate" have allowed to pass on from the technology of continuous pumping of the inhibitor into protected pipelines to the periodic dosing technology. Taking into account a long time of circulation in the system and high temperatures during MEG regeneration process possible degradation products of the inhibitor were studied. N, N-dimethyl-dodecanamine-1, and N, N-dimethyl-tetradecanamine-1 were identified as major degradation products of the corrosion inhibitor CGW-85567.

• Smart Structures and Systems
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• v.11 no.5
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• pp.555-567
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• 2013

An Remote Corrosion Monitoring (RCM) system consists of an anode with low potential, the metallic structures against corrosion, an electrode to provide reference potential, and a data-acquisition system to ensure the potential difference for anticorrosion. In more detail, the data-acquisition (DAQ) system monitors the potential difference between the metallic structures and a reference electrode to identify the correct potential level against the corrosion of the infrastructures. Then, the measured data are transmitted to a central office to remotely keep track of the status of the corrosion monitoring (CM) system. To date, the RCM system is designed to achieve low power consumption, so that it can be simply powered by batteries. However, due to memory effect and the limited number of recharge cycles, it can entail the maintenance fee or sometimes cause failure to protect the metallic structures. To address this issue, the low-overhead energy harvesting circuitry for the RCM systems has designed to replenish energy storage elements (ESEs) along with redeeming the leakage of supercapacitors. Our developed energy harvester can scavenge the ambient energy from the corrosion monitoring environments and store it as useful electrical energy for powering local data-acquisition systems. In particular, this paper considers the energy harvesting from potential difference due to galvanic corrosion between a metallic infrastructure and a permanent copper/copper sulfate reference electrode. In addition, supercapacitors are adopted as an ESE to compensate for or overcome the limitations of batteries. Experimental results show that our proposed harvesting schemes significantly reduce the overhead of the charging circuitry, which enable fully charging up to a 350-F supercapacitor under the low corrosion power of 3 mW (i.e., 1 V/3 mA).

• Corrosion Science and Technology
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• v.7 no.4
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• pp.208-211
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• 2008

Safety operation of main pipelines is primarily provided by anticorrosive monitoring. Anticorrosive monitoring of oil pipeline transportation objects is based on results of complex corrosion inspections, analysis of basic data including design data, definition of a corrosion residual rate and diagnostic of general equipment's technical condition. All the abovementioned arrangements are regulated by normative documents. For diagnostics of corrosion-technical condition of oil pipeline transportation objects one presently uses different methods such as in-line inspection using devices with ultrasonic, magnetic or another detector, acoustic-emission diagnostics, electrometric survey, general external corrosion diagnostics and cameral processing of obtained data. Results of a complex of diagnostics give a possibility: $\cdot$ to arrange a pipeline's sectors according to a degree of corrosion danger; $\cdot$ to check up true condition of pipeline's metal; $\cdot$ to estimate technical condition and working ability of a system of anticorrosive protection. However such a control of corrosion technical condition of a main pipeline creates the appearance of estimation of a true degree of protection of an object if values of protective potential with resistive component are taken into consideration only. So in addition to corrosive technical diagnostics one must define a true residual corrosion rate taking into account protective action of electrochemical protection and true protection of a pipeline one must at times. Realized anticorrosive monitoring enables to take a reasonable decision about further operation of objects according to objects' residual life, variation of operation parameters, repair and dismantlement of objects.

• Journal of the Semiconductor & Display Technology
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• v.12 no.2
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• pp.13-17
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• 2013

In lighting system where several large-area organic light-emitting diode (OLED) lighting panels are involved, panel aging may appear differently from each other, resulting in a falling-off in lighting quality. To achieve uniform light output across large-area OLED lighting panels, we have employed an optical feedback circuit. Light output from each OLED panel is monitored by the optical feedback circuit that consists of a photodiode, I-V converter, 10-bit analogdigital converter (ADC), and comparator. A photodiode generates current by detecting OLED light from one side of the glass substrate (i.e., edge emission). Namely, the target luminance from the emission area (bottom emission) of OLED panels is monitored by current generated from the photodiode mounted on a glass edge. To this end, we need to establish a mapping table between the ADC value and the luminance of bottom emission. The reference ADC value corresponds to the target luminance of OLED panels. If the ADC value is lower or higher than the reference one (i.e., when the luminance of OLED panel is lower or higher than its target luminance), a micro controller unit (MCU) adjusts the pulse width modulation (PWM) used for the control of the power supplied to OLED panels in such a way that the ADC value obtained from optical feedback is the same as the reference one. As such, the target luminance of each individual OLED panel is unchanged. With the optical feedback circuit included in the lighting system, we have observed only 2% difference in relative intensity of neighboring OLED panels.

• International Journal of Computer Science & Network Security
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• v.22 no.2
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• pp.63-74
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• 2022

Repressive measures in the Crimea against the Ukrainian media and the ban on the entry of international and Ukrainian monitoring missions created the conditions for the function of providing information to be performed by representatives of civil society. Such a phenomenon was called Crimean citizen journalism and became a post-occupation phenomenon characteristic of the Crimean information sphere. The journalists' activities are aimed at reporting on human rights violations and repression against Ukrainian citizens who find themselves in conditions of information bans and restrictions. Crimean citizen journalism, which connects the peninsula with the mainland of Ukraine, is monothematic in nature, and its emergence has become a form of nonviolent resistance to the occupation of Crimea. The purpose of the study is to cover the characteristic features, the development of common Crimean citizen journalistic movement features as a social phenomenon, a phenomenon that arose after the occupation through the identification of a modern journalist portrait. The study uses the general scientific method of empirical research as the main one, the sociological method of a questionnaire survey, as well as the methods of classification, generalisation, observation, statistical calculation. An analysis of a survey of Crimean citizen journalists demonstrates the existence of an active, mobile community in Crimea that seeks to provide information and human rights nonviolent resistance to the occupation.