• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.87-91
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• 1998

In this paper, We analyzed the current-voltage characteristics with n-type silicon substrates concentration and temperature variations (Room temperature, 50$^{\circ}C$, 75$^{\circ}C$) in platinum silicide and silicon junction. The electrical parameters of measurement are turn-on voltage, saturation current, ideality factor, barrier height, dynamic resistance in forward bias and reverse breakdown voltage according to variations of junction concentration of substrates and measurement temperature variations. As a result, the forward turn-on voltage, reverse breakdown voltage, barrier height and dynamic resistance were decreased but saturation currents and ideality factor were increased by substrates increased concentration variations in platinum silicide and n-silicon junction. In increased measurement temperature (RT, 50$^{\circ}C$, 75$^{\circ}C$), the extracted electrical parameter values of characteristics were rises by increased temperature variations according to the forward and reverse bias.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.8
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• pp.723-730
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• 2003

The CN(carbon nitrogen) nanofibers were formed by HIP(high isostatic pressure) process. From the field emission measurement, CN nanofibers shows an excellent characteristics of emitter, better than CNTs and carbon nanofibers. The structures obtained can be divided into three groups : bamboo-like fibers, corrugated structures and bead necklace-like fib res. Emission properties of CN nanofibers were investigated for spacing, between anode and cathode, variation. Turn-on fields was 1.4 v/$\mu\textrm{m}$. The time reliability and light emission test were carried out for about 100 hours. We suggest that CN nanofibers can be possibly applied to the high brightness flat lamp because of low turn-on field and time reliability

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1333-1335
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• 2000

In order to turn on the SCR gate, trigger signal source have to provide appropriate gate current and voltage under the gate rating based on the characteristic of SCR, the nature of load and power. It will be essential design factors such as trigger source impedance, trigger signal occurring, signal time width and turn off conditions. Also minimum gate trigger current is changed with the deterioration of SCR. SCR, which is needed large gate trigger current absolutely, is very important for SCR characteristic test because it causes unstable output in the misfile or makes a trouble to pulse trigger circuits. This paper shows scheme to test the performance of SCR with the precision analyzing mechanism and the changing trend of minimum gate current under the trigger conditions.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1165-1167
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• 2000

This paper describes a current fed high frequency resonant inverter used as the power supply for sealing-wax. The proposed inverter can reduce switching losses, noise and voltage stress at turn-on and turn-off. The analysis of proposed circuit uses normalized parameter and characteristic estimation which is needed in each step before design is generally described according to normalized frequency ($\mu$), coefficient of coupling($\kappa$) and all parameters. The theoretical analysis is proved through experiment and this circuit shows that it can be used practically as the power supply system for sealing wax and DC-DC converter.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.218-221
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• 2003

In the response to increasing the demands for electrical energy, much effort aimed to develop and commercialize HTS power equipments have been made around the world. Among them HTS transformer is one of very Promising one. For the development, the cryogenic insulation technology should be established. In this paper V-t characteristics of turn insulator, Kpaton, among insulation components of HTS transformer was discussed with Weibull distribution and n-value. V-t tests of Kapton were conducted using Cu tape electrodes shaped HTS tape depending on wrapping number. The n-values of 2 and 3 times wrapped tape are 27.54 and 30.58. Although breakdown strength of the 3 times one is higher than the 2 times the 3 times one have more weak points with overlapping so it have higher probability of incidental accidents.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.482-487
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• 2005

In the most current Turn-key bidding and Alternative design, is going to establish maintenance plan along with a economical assessment (VE/LCC assessment etc). Generally, establishment of maintenance plan is based on past experiences that are decided upon sensor position and amount with analytic or mechanical control section. But, it is more reasonable that maintenance plan based on level of significance for Probabilistic Risk, with presuming damage probability assessment of structural fracture scenarios. Therefore, in this study it is considered about the technique that an improved maintenance plan of railroad structures using PRA (Probabilistic Risk Assessment) on the basis of structural reliability theory. For this, in the paper, Preventive maintenance plan based on PRA is suggested with an application example of Pansong-Line (Line number 3) railway in Pusan works that actually executed Turn-key design.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.1
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• pp.42-50
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• 2014

Lifting lugs are frequently used in shipyard to transportate and turn over blocks. As the shipbuilding technology develops, blocks has become bigger and bigger, and block management technology takes a more important role in shipbuilding to enhance the productivity. For the sake of economic as well as safe design of lug structure, more rigorous analysis is needed. In this study in order to investigate the strength characteristics of two type of lug, that is, D and T type lugs, non-linear strength analysis has been carried out to compare the ultimate strength characteristics of two types of lug varying in-plane and out-of-plane loading directions. Based on the present numerical analysis results, it can be drawn that T type lug is superior to D type lug from view points of ultimate strength and deformation.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.92-97
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• 2002

We establish a visible light emission from porous polycrystalline silicon nano structure(PPNS). The PPNS layer are formed on heavily doped n-type Si substrate. 2um thickness of undoped polycrystalline silicon deposited using LPCVD (Low Pressure Chemical Vapor Deposition) anodized in a HF: ethanol(=1:1) as functions of anodizing conditions. And then a PPNS layer thermally oxidized for 1 hr at $900 ^{\circ}C$. Subsequently, thin metal Au as a top electrode deposited onto the PPNS surface by E-beam evaporator and, in order to establish ohmic contact, an thermally evaporated Al was deposited on the back side of a Si-substrate. When the top electrode biased at +6V, the electron emission observed in a PPNS which caused by field-induces electron emission through the top metal. Among the PPNSs as functions of anodization conditions, the PPNS anodized at a current density of $10mA/cm^2$ for 20 sec has a lower turn-on voltage and a higher emission current. Furthermore, the behavior of electron emission is uniformly maintained.

• Korean Journal of Child Studies
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• v.29 no.2
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• pp.57-71
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• 2008

This study examined the influences on maternal acceptance-rejection and mediating effects of parenting stress. Participants were 150 mothers of children aged 3 to 6 in Seoul and Jeju. Research questions were analyzed by structural equation modeling. Results showed that children's age, congenital diseases or anomalies, planned pregnancy, and father's occupation influenced maternal acceptance-rejection directly. Mothers' perceived treatment in childhood and fathers' age influenced parenting stress; parenting stress, in turn, influenced maternal acceptance-rejection. Fathers' age influenced parenting stress negatively; parenting stress, in turn, influenced maternal acceptance-rejection positively.

• The Research Journal of the Costume Culture
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• v.11 no.6
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• pp.925-940
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• 2003

The purpose of this study is to analyze the major influence of postmodernism on 20th century fashion. Due to its characteristic traits like pluralism, indeterminacy, and immanence, it can be said that postmodernism in fashion manifests itself in an overlapped and duplicated style. The conceptual side has to do with such various 20th century thoughts as decanonization, deconstruction, populism, and in fashion it is presented as subcultural style, syncretic style, and post-feminist style. The stylistic side of postmodernism in fashion also has to do with fragmentation, hybridity, stress on performance and participation, carnivalization, deconstructive turn, and it is presented as hybrid expression, deconstructive technique, performance, and so on. In the latter part of the 20th century in which postmodernism blossoms in various fields, fashion also participates in the current of the times, together with the rapid stylistic turn, the co-existence of various trends, and the experimental or avant-garde new trials. However, it should be said that all of these tendencies mean not so much blurring of the boundaries between styles as developmental mixture of styles coming from juxtaposition after fully realizing the boundaries of contrast and combination.