• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.1
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• pp.103-112
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• 1999

This is study to estimate the pump induced vibration in time and frequency domain by frequency response function between two points in case of 20Hp and 50Hp centrifugal pumps. The frequency response function has real and imaginary information of signals, and response function has also real and imaginary information. So the vibration force can be obtained from the response function and frequency response function by complex calculation. And it is compared with the theoretically estimated values and it is suggested that the amplitude of vibration with main frequency is about 10~25% of pump and motor weight, and the magnitude of unbalanced mass is about 30~60% of pump and motor weight to estimated vibration force in time domain. There are the other kinds of vibration components with different frequency values of 2~3 times of its main frequency, and these kinds of information are used to control the tuning ratio between operating frequency of pump and structural frequency of concrete slab.

• Journal of Astronomy and Space Sciences
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• v.22 no.2
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• pp.139-146
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• 2005

A model of advection-dominated accretion flows has been highlighted in the last decade. Most of calculations are based on self-similar solutions of equations governing the accreting flows. We revisit self-similar solutions of the simplest form of advection-dominated accretion flows. We explore the parameter space thoroughly and seek another category of self-similar solutions. In this study we allow the parameter f less than zero, which denotes the fraction of energy transported through advection. We have found followings: 1. For f > 0, in real ADAF solutions the ratio of specific heats ${\gamma}$ satisfies 1 < ${\gamma}$ < 5/3 for O ${\leq}$ f ${\leq}$ 1. On the other hands, in wind solutions a rotating disk does not exist. 2. For f < 0, in real ADAF solutions with ${\epsilon}$ greater than zero ${\gamma}$ requires rather exotic range, that is, ${\gamma}$ < 1 or ${\gamma}$ > 5/3. When -5/2 < ${\epsilon}$' < 0, however, allowable ${\gamma}$ can be found in ${\gamma}$ < 5/3, in which case 4{\Omega}_0$,_ is imaginary. 3. For a negative $u_0$,+ with f > 0, solutions are only allowed with exotic ${\gamma}$, that is, 1 < ${\gamma}$ or ${\gamma}$ > (5f/2-5/3)/(5f/2-1)when O < f < 2/5, (5f/2-5/3)/(5f/2-1) < ${\gamma}$ < 1 when f > 2/5. Since ${\epsilon}$' is negative, 4{\Omega}_0$,+ is again an imaginary quantity. For a negative $u_0$,+ with f < 0, ${\gamma}$ is allowed in 1 < 7 < (5|f|/2 + 5/3)/(5|f|/2 + 1). We briefly discuss physical implications of what we have found.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.356-362
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• 2012

This study examined the effects of vocalization on upper extremity muscle activity during reaching task in patients with hemiplegia. Thirteen persons with right brain stroke performed reaching to a cup under four concurrent speech conditions of vocalizing the word "Ah" with hemiplegic side. These four conditions are self-vocalization, external vocalization, imaginary vocalization, and no vocalization. The muscle activity(Biceps brachii, Triceps brachii, Middle deltoid, and Upper trapezius) were measured using MP150. Muscle activity was significantly higher under self-vocalization and external vocalization conditions compared to the muscle activity under imaginary vocalization and no vocalization conditions on triceps brachii muscle.(p<0.05). Triceps brachii muscle was highly correlated with biceps brachii muscle(r=0.777, p<0.05). The results suggest that self-vocalization and external vocalization can be used in facilitating upper extremity movements in patients with stroke. When working with patients with right hemispheric stroke, therapists might explore possibilities of using patient's self-speech to enhance the quality of upper extremity movement performance.

• Journal of the Korean Geotechnical Society
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• v.21 no.2
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• pp.93-103
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• 2005

This study was performed to identify the presence of measurement distortions such as electrode polarization and to investigate the influence of soil water content on complex permittivity at low frequency. In low frequency measurement using two-terminal electrode system, electrode polarization effect was observed at frequencies less than approximately 100 HBz. The analysis for real permittivity should be performed at frequencies above 100 kHz in order to exclude electrode polarization effect in the analysis of real permittivity at low frequency measurements. For a given soil, both of real and effective imaginary permittivity of wet soil increased continuously with volumetric water content. This is evidenced by the facts that the real permittivity is proportional to the number of dipole moments per unit volume and effective imaginary permittivity is effected by the conduction due to water. However, proportional relation between real permittivity and volumetric water content is valid at upper MHz frequencies.

• Korean Journal of Social Welfare Studies
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• v.42 no.3
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• pp.121-155
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• 2011

The purpose of this study as a research of experience of sexual offenders who are in confinement in prisons and forensic facilities is to theoretically investigate fundamental structures of their experiences and to practically construct basic data to present intervention programs of sexual offenders. This study was conducted by hermeneutical and phenomenological methods invoked of the analytic framework of Van-Manen (1990) about seven sexual offenders. The data were collected through in-depth interviews, and the results of the interpretation are shown as perception that they were victims of public opinion, the mark of Cain, loss of opportunity of examination caused by show window, collective differentiation through distinction, expression of metaphysical being that wants to slip out of the skin, counterplot of scientific management techniques, undifferentiation from the Imaginary, sexual acts shown as inverted communication, discovering dominant domain as forming reaction to being controlled, not being free from capitalistic attributes in which even children's sex is commercialized, distortion in socialization of sexual identity, paternity stamped as embodiment of suppressed desire, recovery of lost virginity of mother through children, and family as a name broken to pieces.

• Journal of Industrial Convergence
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• v.21 no.9
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• pp.49-56
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• 2023

ID is used as identifying information and password as user authentication for ID-based authentication. In order to have a secure user authentication, the password is generated as a hash value on the client and sent to the server, where it is compared with the stored information and authentication is performed. However, if even one character is incorrect, the different hash value is generated, authentication will be failed and cannot be performed and various functions cannot be applied to the password. In this study, we generate several hash value including imaginary number of entered password and transmit to server and perform authentcation. we propose a technique can grants the right differentially to give various rights to the user who have many rights by one account. This can defend shoulder surfing attack by imaginary password and provide convenience to users who have various rights by granting right based on password.

• Journal of Practical Engineering Education
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• v.16 no.3_spc
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• pp.327-332
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• 2024

The spread of smart phones provides users with a variety of services, making their lives more convenient. In particular, financial transactions can be easily made online after user authentication using a smart phone. Users easily access the service by authenticating using a PIN, but this makes them vulnerable to social engineering attacks such as spying or recording. We aim to increase security against social engineering attacks by applying the authentication method including imaginary numbers when entering a password at the door lock to smart phones. Door locks perform PIN authentication within the terminal, but in smart phones, PIN authentication is handled by the server, so there is a problem in transmitting PIN information safely. Through the proposed technique, multiple PINs containing imaginary numbers are generated and transmitted as processed values such as hash values, thereby ensuring the stability of transmission and enabling safe user authentication through a technique that allows the PIN to be entered without exposure.

• Journal of Fashion Business
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• v.17 no.1
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• pp.64-80
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• 2013

A new technology of fashion show is opening the digital era and an imaginary fashion show is now arising as a new form of fashion show which allows one to enjoy a collection through the monitor without holding a real fashion show. Digital fashion show allows designer to create infinite ideas by articulating the designer's concept through not only garments but also other factors. In this research, We will analyze cases which are mixtures of digital technology and fashion show and will suggest a new paradigm of fashion show by producing an imaginary fashion show which cannot be easily articulated in an ordinary real fashion show, articulated by garments created by digital technology and graphic effects. The program used for this study is 'DC Suite 2.0' developed by Physan and Digital Clothing Center of Seoul National University, available for 2D pattern production and 3D simulation. In addition, in order to enhance representation of the visual effects, Maya's Qualoth and V-ray program which could be compatible with 'DC Suite' were used to make 3D digital fashion show.

• The Journal of the Korea Contents Association
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• v.16 no.2
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• pp.525-536
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• 2016

is basically based on a written history but is narrated for an unwritten history with imagination. This study explored whether viewers of tow films and regard them as a real story or an unreal story. Analysis of film contents and data from a nationwide online survey(N = 300) were executed. This study found the following. First, viewers consider a true story but a imaginary story. Second, viewers show different ideologial and emcotional evaluation, and strength of memory between two films. Finally, viewers are not likely to evaluate performative value of two history films, which suggest a pluralistic interpretation of history, as they regard the films as an imaginary story or a recreation.

• Environmental and Resource Economics Review
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• v.23 no.4
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• pp.719-746
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• 2014

This study attempts to estimate the value of the water quality improvement by deriving the equilibrium price of the water pollutant emission permit for the imaginary water pollutant emission trading market. It is reasonable to say that there is already an implicit social agreement for the unit value of water pollutant, when the government set the Total Water Pollutant Loading System for the major river basin as a part of the Comprehensive Measures for Water Management, particularly for the Nakdong River Basin. Therefore, we can derive the unit value of water pollutant emission, which is already implied in the pollution allowance for each city or county by the Total Water Pollutant Loading System. Once estimated, it will be useful to the economic assessment of the water quality related projects. An imaginary water pollutant emission trading system for the Nakdong River Basin, where Total Water Pollutant Loading System is already effective, is constructed for the estimation of the equilibrium price of water pollutant permit. By estimating marginal abatement cost curve or each city or county, we can compute the equilibrium price of the permit and then it is regarded as the economic value of the water pollutant. The marginal net benefit function results from the relationship between the emission and the benefit, and then the equilibrium price of permit comes from constructing the excess demand function of the permit by using the total allowable permit of the local government entity. The equilibrium price of the permit would be estimated to be $1,409.3won/kg{\cdot}BOD$. This is within reasonable boundary compared for the permit price compared to foreign example. This permit price would be applied to calculate for the economic value of the water quality pollutants, and also be expected to use directly for the B/C analysis of the business involved with water quality change.