• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.299-302
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• 2002

The second harmonic component is commonly used for blocking differential relay in Power transformers. However it is difficult to distinguish between inrush and internal winding fault with differential current protective relaying. This paper proposed a new method using nuro-fuzzy. The used data in nuro-fuzzy algorithm are 3-phase primary voltage and fundamental harmonic of differential current. Various states of transformer are simulated using BCTRAN and HYSDAT of EMTP. As a result of applying the algorithm in various cases, the correct discrimination between internal winding fault and inrush performed.

• The Korean Journal of Nuclear Medicine
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• v.39 no.2
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• pp.141-145
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• 2005

Hypoxia (decreased tissue oxygen tension) is a component of many diseases such as tumors, cerebrovascular diseases and ischemic heart diseases. Although hypoxia can be secondary to a low inspired $pO_2$ or a variety of lung disorders, the most common cause is ischemia due to an oxygen demand greater than the local oxygen supply. In the heart tissue, hypoxia is often observed in persistent low-flow states, such as hibernating myocardium. Direct "hot spot" imaging of myocardial tissue hypoxia is potentially of great clinical importance because it may provide a means of identifying dysfunctional chronically ischemic but viable hibernating myocardium. A series of radiopharmaceuticals that incorporate nitroimidazole moieties have been synthesized to detect decreased local tissue pO2. In contrast to agents that localize in proportion to perfusion, these agents concentrate in hypoxic tissue. However, the ideal agents are not developed yet and the progress is very slow. Furthermore, the research focus is on tumor hypoxia nowadays. This review introduces the myocardial hypoxia imaging with summarizing the development of radiopharmaceuticals.

• Journal of the Korean Society of Industry Convergence
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• v.2 no.2
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• pp.139-146
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• 1999

Combustion Characteristics of the wood chips(balsa chips) were experimental studied as fundamental investigation of the thermal recycle system of the urban dust. The urban dust contains plastics vegetable and lot of wood material. Then, a wood was chosen as an example of the component of urban dust. A small wood chip was burned in a electric furnace and mass reduction rate during volatile and combustion states were recorded by the micro-electric balance and the combustion flame shape took a photograph by video camera at the mass of wood chips and ambient temperature in the furance. Ignition delay took the minimum value when the mass of the test chip was 0.3g. When a mass of the test chip was smaller then 0.001g, combustion with flame did not burnt.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2002.07a
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• pp.97-102
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• 2002

Life Science Research Center of SK Chemicals has developed a 3rd-generation anticancer platinum drug for the first time in the nation′s 100-year-old pharmaceutical industry. The Korea Food and Drug Administration (KFDA) approved the sale of "Sunpla" (code name SKI 2053R, general name : Heptaplatin) on July 14, 1999 for the treatment of advance, metastatic gastric cancer. Cisplatin, the 1 st-generation anticancer drug, which was developed by Bristol-Myers of the United States in 1976, is one of the most potent anticancer drugs and is a major component of combination chemotherapy for a variety of human cancers. However its clinical usefulness has frequently been limited not only by undesirable side effects such as severe renal toxicity, nausea, vomiting, ototoxicity, and neurotoxicity but also by the development of resistance. Carboplatin, the 2nd-generation anticancer platinum drug, which was also developed by Bristol-Myers in 1986, has modified the problems of the renal and gastrointestinal toxicities of cisplatin. Carboplatin, however, has no enhanced therapeutic efficacy over cisplatin and does not possess the property to overcome cross-resistance to cisplatin.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.6
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• pp.468-476
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• 2002

This paper deals with heat and mass transfer characteristics and performance evaluation of a counter flow double-tube condenser for a multi-component refrigerant mixture. The local heat and mass transfer characteristics of ternary zeotropic refrigerant mixtures composed of HFC32/HFC125/HFC134a are evaluated for a counter flow double-tube condenser cooled by water. Then, the local values of vapor quality, thermodynamic states at bulk vapor, vapor-liquid interface and bulk liquid, heat flux and condensation mass flux are obtained. The heat exchange performance for ternary zeotropic refrigerant mixtures composed of HFC32/HFC125/HFC134a on the total pressure drop and the heat transfer characteristics are also compared with those for R404A, R410A, R502, R22, R32, Rl23 and R134a.

• Proceedings of the Korea Concrete Institute Conference
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• 1992.04a
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• pp.126-130
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• 1992

Recently, fatigue problem become a critical issue in the design of prestressed concrete bridges due to the increase of traffic volumes and use of high-strength materials. Most existing studies are mainly concerned with the fatigue behavior of component materials only such as concrete, reinforcing bars, and prestressing steels and few studies exist that deals with the fatigue behavior of bridge members. An improved analytic formulation for both uncracked and cracked prestressed concrete composite section with cyclic creep effect is developed to take into account the change of neutral axis with crack propagation. The procedure also enables to investigate serviceability limit states, deflection and crack width. The present study allows more realistic analysis and design of prestressed concrete composite girder bridges under fatigue loadings.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.552-554
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• 2003

The second harmonic component is commonly used for blocking differential relay in power transformers. However, it is difficult to distinguish between inrush and internal winding fault with differential current protective relaying. This paper proposed a new method using Nuro-Fuzzy System based on HCM(Hard C-Means). The proposed system is more objective and systematic than existing model. The data used in input are 3-phase primary voltage and fundamental harmonic of differential current. Various states of transformer are simulated using BCTRAN and HYSDAT of EMTP. As a result of the application of algorithm in various cases, the exact discrimination between internal winding fault and inrush is performed.

• The Journal of Sustainable Design and Educational Environment Research
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• v.11 no.3
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• pp.25-35
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• 2012

Even though newly formed schools do struggle to strengthen their security in safety, existed schools have limitations for active response against natural disaster. From analyzing the results of accident cases and states in misfortune and the safety supervision of school facilities, it is said that damages by wind, flood and fire are typical types of disaster accidents. Also, according to the basic law of misfortune and the safety supervision, it emphasizes education, training, and actions that prevent from being a victim of natural disaster. In terms of these finding, establishing disaster safety organization, control system and having students an opportunity to learn how to response against disaster should be critical component in managing disaster safety of school facilities.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.203-204
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• 2012

This paper presents the method to design the inductor and capacitor value considering the ripple component that may be generated by three operating states of the Quasi Z-source inverter at the impedance network. Based on the analysis of each operation mode, the equations of the capacitor voltage and inductor current are derived. In order to simplify the design processing, design equations of the impedance network are derived where the capacitor voltage and inductor current are lineared. The validity of the design method is verified with the simulation result using PSIM and experimental result using 32-bit DSP.

• Communications for Statistical Applications and Methods
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• v.25 no.6
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• pp.619-631
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• 2018

Functional data analysis continues to attract interest because advances in technology across many fields have increasingly permitted measurements to be made from continuous processes on a discretized scale. Particulate matter is among the most harmful air pollutants affecting public health and the environment, and levels of PM10 (particles less than 10 micrometers in diameter) for regions of California remain among the highest in the United States. The relatively high frequency of particulate matter sampling enables us to regard the data as functional data. In this work, we investigate the dominant modes of variation of PM10 using functional data analysis methodologies. Our analysis provides insight into the underlying data structure of PM10, and it captures the size and temporal variation of this underlying data structure. In addition, our study shows that certain aspects of size and temporal variation of the underlying PM10 structure are associated with changes in large-scale climate indices that quantify variations of sea surface temperature and atmospheric circulation patterns.