• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2216-2217
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• 2008

This paper write about earth system for the prevention electric shock and a protection of equipment in england. The IEC60364 and BSI(British Standards Institution) define earthing method(IT, TT, TN-C, TN-S, TN-C-S)-BSI is british standards and in case of england almost use the TN system. TN system can classify TN-S & TN-C-S(PME). The findings on survey in england are used the TN-S system and TN-C-S system about 70% and residue 30% are used TT system and IT system from the exiting state of things.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.8
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• pp.113-120
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• 2007

This paper presents the electric shock hazards and solutions of loss of the combined protective and neutral (PEN) conductor in TN-C-S system. In order to mitigate the touch voltage on exposed-conductive-parts in a break in the PEN conductor, the touch voltages on exposed-conductive-parts in a break in the PEN conductor were experimentally investigated as a function of the ground resistances of the source grounding electrode and customer's additional grounding electrode. As a result, the equipotential bonding is one of important requirements for installations supplied by TN-C-S system. A solution of mitigating the touch voltages on exposed-conductor-parts caused by a loss of the PEN conductor would be the installation of the additional grounding electrode at the customer's service entrance. The ground resistance of additional grounding electrode necessary to limit the touch voltage to a safety voltage of less than 50[V] depends on the load and circuit parameters. In addition, the undervoltage sensing devices oner affordable solutions to detect a loss of the PEN conductor in TN-C-S system.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.1
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• pp.56-62
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• 2010

This paper describes the analysis of loop impedance characteristics by impedance alteration of protective conductors and operating characteristics of electric leakage circuit breaker by each earth systems(TT system, TN-S system and TN-C system) in IEC 60364. As a result, loop Impedance was affected by resistance & inductance. The current& voltage characteristics about earth system were identified that the TN-S system was high fault current & low touch voltage. TN-C system was almost same the TN-S system but TT system was low fault current & high touch voltage.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.8
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• pp.1163-1168
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• 2013

The maximum allowable value of loop impedance($Z_s$) to secure the operation of overcurrent protective devices and the safety for indirect contact is a very important in TN-C-S system. The loop impedance is divided into inner loop impedance which consumer can adjust and external loop impedance($Z_e$) which only electric operator can adjust. Thus, an external loop impedance which limits to less than a certain value is a very important factor for human body protection against electric shock in TN-C-S system. The concept of loop impedance($Z_s$) is recently introduced to the domestic, the study about external loop impedance is yet insufficient. However, the study about the reference impedance as specified by the IEC 60725 standard to improve the quality and reliability of the power supply is being made. In this paper, reference value of external loop impedance($Z_e$) to meet domestic environment will be proposed by the nationwide measurement and statistical analysis.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.5
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• pp.58-64
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• 2012

In electric power supply systems, an earthing system determines the electric potential of the conductors related to that of the Earth's surface. The choice of earthing system has implications for the safety of the power supply systems. There are considerably different regulations for earthing (grounding) systems in each country. A protective earth(PE) conductor ensures that all exposed conductive surfaces are at the same electric potential as the earth surface. This paper deals with that when PEN conductor of TN-C-S system is disconnected, dangerous touch voltage causes personnel body to be harmed and human being's property to be damaged seriously. For this reason, this paper explains how serious problems can occur when the fault current flows. As a consequence, we can understand how we can design earthing system properly to ensure the personnel safety against earth faults. The result shows the way that TN-C-S system can be applied safely in Korea.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.59-62
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• 2009

In electrical power supply systems, an earthing system determines the electrical potential of the conductors relative to that of the Earth's conductive surface. The choice of earthing system has implications for the safety of the power supply. Note that regulations for earthing (grounding) systems vary considerably among different countries. A protective earth(PE) connection ensures that all exposed conductive surfaces are at the same electrical potential as the surface of the Earth, This paper investigates that when PEN conductor of TN-C-S system is disconnected, dangerous touch voltage is caused at personnel body. According to this paper, we can understand that when TN-C-S system is applied in Korea, what we should set up to ensure the personnel safety from fault current.

• Journal of Yeungnam Medical Science
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• v.18 no.1
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• pp.13-29
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• 2001

The enzyme activities of creatine kinase (CK), its isoenzyme MB (CK-MB) and of lactate dehydrogenase isoenzyme 1 (LD-1) have been used for years in diagnosing patients with chest pain in order to differentiate patients with acute myocardial infarction (AMI) from non-AMI patients. These methods are easy to perform as automated analyses, but they are not specific for cardiac muscle damage. During the early 90's the situation changed. First, creatine kinase ME mass (CK-MB mass) replaced the measurement of CK-MB activity. Subsequently cardiac-specific proteins, troponin T (cTnT) and troponin I (cTnI) appeared and displacing LD-1 analysis. However, troponin concentrations in blood increase only from four to six hours after onset of chest pain. Therefore a rapid marker such as myoglobin, fatty acid binding protein or glycogen phosphorylase BB could be used in early diagnosis of AMI. On the other hand, CK-MB isoforms alone may also be useful in rapid diagnosis of cardiac muscle damage. Myoglobin, CK-MB mass, cTnT and cTnI are nowadays widely used in diagnosing patients with acute chest pain. Myoglobin is not cardiac-specific and therefore requires supplementation with some other analyses such as troponins to support the myoglobin value. Troponins are very highly cardiac-specific. Only the sera of some patients with severe renal failure, which requires hemodialysis, have elevated cTnT and/or cTnI without there being any evidence of cardiac damage. The latest studies have shown that elevated troponin levels in sera of hemodialysis patients point to an increased risk of future cardiac events in a similar manner to the elevated troponin values in sera of patients with unstable angina pectoris. In addition, the bedside tests for cTnT and cTnI alone- or together with myoglobin and CK-ME mass can be used instead of quantitative analyses in the diagnosis of patients with chest pain. These rapid tests are easy to perform and they do not require expensive instrumentation. For the diagnosis of patient with chest pain, routinely myoglobin and CK-ME mass measurements should be performed whenever they are requested (24 h/day) and cTnT or cTnI on admission to the hospital and then 4-6 and 12 hours later and maintained less than 10% in imprecision.

• The Korean Journal of Ecology
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• v.1 no.1
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• pp.17-23
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• 1977

Flowering dates of 389 plant species in the Hongneung Arboretum, Seoul, had been recorded from 1968 through 1975. The thermal analysis on the air temperature as the key factor determining the first flowering date, with climatological data obtained in the Arboretum, were undertaken by Nuttonson's Index (1948) and Lindsey & Newman's Index (1956). The results and conclusion in this study are as follow; Peak in the bell shape distribution curve of the species and first flowering dates, largely, was early May. Flower spans of most species were 10 to 20 days, neverthless, some species flower only a few days while others may stay flowering a hundred days even more. Increase-curves of summation temperature from early spring through late-summer showed almost the same mode in both Nuttonson;s Index (Tn) and Lindsey & Newman's Index (T1). These Indices manifested the exponential curve, increasing slowly at the beginning of spring chiefly but rapidly from the middle part of April. The equation of the linear relationahip between Tn and Tl as far as in thisstudy is as follow. Tl=230Tn It appears that the distribution of summation temperature, below Tn=400°C·day, affects the first flowering, even though it could be modified somehow by the distribution of precipitation, day length and others. Nuttonson's Index (Tn.f) and Lindsey & Newman's Index (Tl.f) upon the thermal amount first flowering dates have been respectively simulated as follow. Tn.f=θa + C Tl.f=230θa + 230C where θ is air temperature 10°C, a and C are a constant.

• Korean Journal of Optics and Photonics
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• v.30 no.2
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• pp.59-66
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• 2019

We report highly sensitive detection of myocardial infarction biomarkers, such as myoglobin and cTnI, within several hundred seconds using a rotating-analyzer ellipsometer and a biosensor with biochips fabricated on a $SiO_2$-coated tilted silicon substrate. We choose the running buffer to be pure phosphate-buffered saline (PBS) or 10% mixed human serum. When we choose the running buffer to be pure PBS, we obtain diagnostic densities of pure myocardial infarction biomarkers of up to 1 ng/ml and 5 pg/ml respectively. Meanwhile, when we use PBS with 10% human serum, the measured densities of myoglobin and cTnI were up to 1 ng/mL and 1 pg/mL respectively. The measured diagnostic densities are less than 1/15 and 1/80 (in cases of myoglobin and cTnI respectively) of those referenced by the World Health Organization.

• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.183-187
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• 1989

The bacteriophage Mu and transposon Tn5 containing plasmid pJB4JI-transferred transposon Tn5 to Caulobuter crescentus. When several thousand of transposon Tn5 insertion mutants were examined, we found auxotrophic and motility mutants at frequencies of 2％ and 3％, respectively. Transposition of transposon Tn5 was analyzed by the reverse field electrophoresis and Southern hybridization. The results indicated that transposon Tn5 was randomly inserted to Caulobuter crescentus chromosome but the plasmid vector, pJB4JI, was not maintained.