• Environmental Analysis Health and Toxicology
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• v.20 no.4 s.51
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• pp.343-350
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• 2005

In order to investigate the of effects of nalbuphine on immune system in mice, we examined the various immunological parameters. After single oral administration of nalbuphine (130, 260, 390 mg/kg, i.p.) to female ICR mite, the weights of bodies and organs (thymus, spleen, liver, kidney), and hematological parameters were examined on day 2, 4, 6, and 8. The increased rate of body weight, relative weight of organ, and hematological parameters in nalbuphine -treated groups, were not significantly changed when compared with control group. However, number of WBC was decreased by the treatment of nalbuphine. To assess the effects of nalbuphine on humoral immune responses, splenic IgM plaque forming cell (PFC) and serum IgM were assayed. When nalbuphine wat administered after immunization with SRBC, but not before immunization, splenic IgM PFC and ,serum IgM level against SRBC were significantly lowered in a dole -dependent manner. These results indicate that the suppressive effects of nalbuphine on primary humoral immune response may be dependent on the timing of its administration relative to the initial antigenic sensitization.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.1
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• pp.43-51
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• 1998

Most of fuel-injection system operated with mechanical methods are difficult to control the injection quantity and injection timing as well as injection rate exactly. Moreover high pressure injection scheme is never be realized with conventional one. On the other hand, serious air pollution can be lessened with injection system equipped with those functions. Therefore, electronically controlled Unit Injuctor(UI) appeared to satify above mentioned desires. However, it is still difficult that the most important part, especially solenoid valve, is analyzed precisely, because of the existence of complex combination of electromagnetics, electrics and dynamic problems. In this study, experimental and theoretical analysis are accomplished for understanding of solenoid valve characteristics and further its design. As the result, the follows are obtained 1) As the increase of wire diameter, the response time became shorter and optimal inductance existed in relative with the response time and wire diameter. 2) According to increasing input voltage, the traction force increased, otherwise the response time was shortened. 3) As the increase of armature stroke, the traction force decreased and the response time became longer.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.1
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• pp.95-102
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• 2014

This paper presents zero crossing point(ZCP) estimation methods considering discretization error for a high speed brushless DC(BLDC) motor drive. The ZCP is estimated by detecting the change of back-EMF polarity for the BLDC sensorless drive, and the discretization error exist on the estimated ZCP. The discretization error of the ZCP is a cause of the delay of a commutation timing of current and increment of a current ripple factor. Besides a delay of a ZCP estimation brings on the limitation of a speed range for the BLDC sensorless drive. The compensation method based on the error analysis with probability theory for reducing the effects of the discretization error of the ZCP is proposed. Also a ZCP estimation method according to the Back-EMF patterns is proposed to widen the speed range for the BLDC sensorless drive. The proposed methods are verified by the experiment.

• Journal of Distribution Science
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• v.17 no.7
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• pp.27-38
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• 2019

Purpose - This study analyzes effects of word of mouth intention of restaurant product via SNS on trust of products, purchase intention, and word of mouth intention targeting restaurant customers. Research design, data, and methodology - Targeting restaurant customers, 500 surveys were distributed in restaurants located in Seoul (where restaurants are clustered, such as Myeongdong, Dongdaemoon Station Shopping Center, and Sadangdong) between July 1st, 2016 and July 30th, 2016. Among those, 490 were collected, and 478 were used for analysis excluding those with no answer or insincere answers. Results - SNS word of mouth information characteristics had significant effects on trust of restaurant product in the order of vividness, neutrality, and timing. Trust on restaurant product has significant effect on perceived risks (-) and perceived benefits (+) by SNS. While perceived benefits of restaurant product on SNS has effect on purchase intention, perceived risks of restaurant product on SNS does not affect purchase intention. Perceived benefits of restaurant product on SNS has significant effect on word of mouth intention, whereas perceived risks of restaurant product on SNS does not have significant effect on word of mouth intention. Conclusions - As marketing through SNS can bring about a huge reduction effect in terms of marking cost, it can be utilized as an effective promotion by not only large restaurant corporations, but also small restaurants.

• Journal of KIISE:Information Networking
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• v.37 no.4
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• pp.307-311
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• 2010

Most wireless ad hoc networks use sender-centric carrier sensing where a data sender determines the transmission timing through channel assessment. However, sender-centric carrier sensing suffers from both exposed and hidden terminal problems even with physical and virtual carrier sensing. In this paper, we propose a new receiver-centric carrier sense (RCS) technique where a data receiver triggers packet transmission based on local channel assessment. Through both numerical analysis and simulation studies, we show that the proposed RCS achieves up to 20.9% higher throughput than previous receiver-centric approaches.

• Korean Journal of Adult Nursing
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• v.15 no.3
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• pp.463-471
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• 2003

Purpose: This study was aimed at providing scientific evidence for minimizing ventilator-associated pneumonia(VAP) by identifying appropriate timing of exchange of circuit for mechanical ventilator that is well suitable for the medical environment of intensive care units of hospitals in Korea. Method: This was a quasi-experimental study with a convenience sample of 19 adult subjects aged over 18 years who were admitted to the NS ICU of C university hospital, and placed on mechanical ventilator. The subjects were placed in two groups, compared on the incidence rate of VAP after they received exchange of circuit either at 1-week interval (N =10) or 2-week interval (N = 9). Result: 1) When considering 1000 days as the standard unit of analysis for incidence, the incidence rate of VAP was 7.19 cases at the 1-week cycle exchange group and 15.23 at the 2-week cycle exchange group, showing no statistically significant difference between the two groups. 2) There were a total of 3 types of bacteria isolated from the patients with VAP, including 2 cases with P. aeruginosa, 1 case with Streptococcus group F and A. baumannii. Conclusion: With thorough hand washing and strict management of tracheal tube of mechanical ventilator as well as use of tracheal intubation techniques, exchange cycle of circuit of mechanical ventilator by nurses may be changed from 1-week to 2-week interval.

• Journal of Biomedical Engineering Research
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• v.2 no.1
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• pp.47-54
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• 1981

This paper deals with a new approach to the modelling of neural interactions in the cerebellar cortex to construct a general purpose electronic simulation model. Since physiological data show that cerebellar neural activity changes in an approximately pulse manner in response to pulse stimulation, the differences in timing between excitation and inhibition of cerebellar cells will be treated as pure time delays and the transfer functions of the cells will be presented by pure gains. The parameters to be discussed in this paper are the coupling coefficients between a cell and its several inputs, the magnitude of a coupling coefficient which is presented as a measure of how much influnce a particular has on its target cell. And also this paper has been proposed that the cerrbellum engaged in improving the overall performance of the motor control system, i.e., the cerebellum is a compensator.

• Journal of Astronomy and Space Sciences
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• v.18 no.3
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• pp.191-208
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• 2001

We have recently compiled a database of the properties of 192 impact craters, which supercedes previous compilations. Using our database, the impact structures found in North America, Europe and Australia have been examined; these cratonic areas have been relatively stable for considerably long geological periods, and thus have been best preserved. It is confirmed that there is a close correlation between the geological epoch boundaries, the epochs of mass extinctions, antral the "timing" of impacts. In addition, the terrestrial cumulative flux of objects >20km is found to be $1.77{\times}10^{-15}km^{-2}yr^{-1}$, over the last 120 Myr, which is much smaller than the published values in McEwen et al. (1997) and Shoemaker (1998) ($5.6{\pm}2.8{\times}10^{-15}km^{-2}yr^{-1}$. For terrestrial impact structures with D> 50 km, the apparent cumulative flux over the last 2450 Myr is ~50 times smaller than the corresponding value for the Moon. If we assume that the Earth and the Moon suffered the same level of bombardment over this time, this would mean that the actual flux of impacting bodies, capable of making craters with D)50 km, was ~ 50 times larger than the apparent flux estimated from the currently known terrestrial records.

• The Journal of Asian Finance, Economics and Business
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• v.5 no.3
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• pp.157-167
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• 2018

This research aims to generalize the conceptual basis of precariousness of employment, study the factors and scale of unsustainable of employment in the countries of the Eurasian Economic Union (EAEU). The concept of precariousness of employment is formed in social and economic studies about 40 years ago, but objective and subjective conditions and forms of unsustainable employment existed before. This study proposes a classification of forms of precariousness of employment on 16 criteria: the duration and timing of agreements, contract terms, the nature of income; the degree of labor autonomy; the level of formality; the level of openness; the level of vulnerability; the conditions of growth of qualification; the level of flexibility; the level of stability; regularity; the severity of the danger of work; in relation to the workplace; the quality of employment, the level of social security. In this research highlighted factors (globalization, demography, migration, structure factors, shadow and informal economy, social development and living standards, unemployment), and systematized certain trends of precariousness of employment, channels and means, forms of manifestation. The empirical analysis identified of the labor potential of the Eurasian countries and new quantitative estimates of the levels of unsustainable employment in the Eurasian Economic Space.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.2
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• pp.38-45
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• 2000

In this paper, an approach of modeling the optical interconnection system by SPICE simulation is presented. SPICE simulations with equivalent circuit models for optical devices are performed in a stable manner. From the simulated results, eye diagrams for receiver output and BER are obtained. Timing jitter due to laser diode turn-on delay effects can be found under various bias conditions. Using this approach, various system parameters such as bit rate, BER, dissipated transmitter power, and bias conditions can be optimized. It is expected that this approach will find useful applications such as Gigabit Ethernet and ATM.