• Korean Management Science Review
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• v.28 no.3
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• pp.95-112
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• 2011

The Internet has generated a number of online review sites where dissatisfied consumers can easily articulate their opinions and comments on products or services. Little attention, however, has been directed to investigating the relationship between negative electronic word-of-mouth (eWOM) and its critical determinants that affect consumers' purchasing behaviors. This study attempts to explore the influence of the key determinants of consumers' negative eWOM behaviors, including their social relationships online. The results show that tie strength is positively associated with the proposed determinants, such as information credibility, external search efforts, and product involvement. Further, we find that perceived risk plays a mediating role in the relationship between consumers' intention to spread eWOM and its key determinants.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2753-2756
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• 2003

A convenient, tunable loop-gain negative impedance circuit that increases input impedance of a front-end in a bioimpedance measurement has been proposed. Since the proposed circuit comprises wide-band operational amplifiers, selecting operational amplifiers is easy, while an operational amplifier of proper bandwidth should be chosen to use conventional circuit. Also, since loop-gain can be controlled by a feedback resistor connected serially with a feedback capacitor, loop-gain is tunable with a potentiometer. The input impedance of the proposed circuit is two times larger than that of the conventional circuit. Furthermore, closed loop phase response of the proposed circuit is better than that of the conventional circuit or without a negative capacitance circuit. The implemeted, proposed circuit showed stable operation and a zero input capacitance.

• Journal of Information Technology Services
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• v.14 no.2
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• pp.111-128
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• 2015

In this paper, we examined the effects of emotional and individual variables on flow in the usage of mobile application. We selected four relevant emotional and individual factors such as positive affect, negative affect, addiction and habituation. We also attempted to figure out the moderating role of communication in the effect of positive affect, negative affect, and addiction on the flow. For empirical analysis, we surveyed real users of mobile application and applied PLS (Partial Least Square) methodology for SEM (Structural Equation Modeling). As a result, we found that positive affect, addiction, and habituation have significant and positive impact on the flow. Furthermore, we also found that the moderating effects of communication on the relationships between positive/negative affect and communication are significant. Our findings provide important theoretical grounds for the effects of human behavior and emotion on the flow of mobile applications. Lastly, we also suggest significant managerial implications for the development mobile applications industry.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05a
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• pp.35-37
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• 2001

The Al etching was studied employing negative ions generated in the downstream $Cl_2$ plasma. In order to etch the Al film practically on an insulator covered electrode coupled with RF power, reduction of the negative self bias voltage (Vdc) was examined using a magnetic filter which trapped electrons. Addition of $SF_6$ and $H_2$ to a $Cl_2/BCl_3$ mixture reduced significantly Vdc.

• Journal of Information Technology Applications and Management
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• v.19 no.2
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• pp.233-247
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• 2012

There are so many studies on perceived risk and purchasing intention. But the results of those studies were inconsistent; some studies showed the positive effect of perceived risk on purchasing intention; others showed the negative effect. This research supposed that the inconsistence of studies resulted from the difference of group innovativeness and set up research hypotheses : among users from the lower innovativeness group, perceived risk has a negative effect on purchasing intention, but from the higher group, perceived risk has a positive effect on purchasing intention. We compared Internet shopping mall users of South Korea representing low innovativeness with those of China representing high innovativeness. The results provided that among South Korean users, perceived risk had the statistically insignificant negative effect on purchasing intention, but among Chinese users, it had the statistically significant positive effect on purchasing intention. Additionally, this study found that perceived risk influenced users' fun which in turn influenced purchasing intention.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.439-440
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• 2008

A high-speed DCO is proposed that uses the negative-skewed delay scheme. The DCO consists of a ring of inverters with each PMOS transistor driven from the output of 3 earlier stage through a set of minimum-sized pass-transistors. The digitization of negative-skewed delay is achieved by selecting pass-transistors turned on and digitizing the gate voltages of the selected pass-transistors. The proposed 7-stage DCO has been simulated using 1.8V, $0.18\;{\mu}m$ TSMC CMOS process to obtain a resolution of 3ps and an operation range of 2.88-5.03GHz.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.49-52
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• 2003

In this paper, we propose new speech feature parameter using NMf(Non-Negative Matrix Factorization). NMF can represent multi-dimensional data based on effective dimensional reduction through matrix factorization under the non-negativity constraint, and reduced data present parts-based features of input data. In this paper, we verify about usefulness of NMF algorithm for speech feature extraction applying feature parameter that is got using NMF in Mel-scaled filter bank output. According to recognition experiment result, we could confirm that proposal feature parameter is superior in recognition performance than MFCC(mel frequency cepstral coefficient) that is used generally.

• Journal of applied mathematics & informatics
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• v.30 no.1_2
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• pp.135-145
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• 2012

Traditionally, ERM (Equivalent Random Method) is used to determine number of circuits in an overflow circuit group with rough traffic which has vmr(variance to mean ratio) greater than one. Recently, IPP(Interrupted Poisson Process) approximate method which represents the collective feature of the overflow has been introduced. The negative binomial loss formula can be applied to determine the required number of circuits in the overflow circuit group. In this paper, we deal with the negative binomial loss formula and determination method of number of circuits. We also analyze and compare these three loss formulas.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.6
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• pp.546-550
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• 2013

We propose a novel negative differential resistance (NDR) device with ultra-high peak-to-valley current ratio (PVCR) by combining pn junction diode with depletion mode nanowire (NW) transistor, which suppress the valley current with transistor off-leakage level. Band-to-band tunneling (BTBT) Esaki diode with degenerately doped pn junction can provide multiple switching behavior having multi-peak and valley currents. These multiple NDR characteristics can be controlled by doping concentration of tunnel diode and threshold voltage of NW transistor. By designing our NDR device, PVCR can be over $10^4$ at low operation voltage of 0.5 V in a single peak and valley current.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.1
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• pp.59-62
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• 2017

CNT (carbon nanotube) resistors with low resistance and negative TCR (temperature coefficient of resistance) were fabricated with yarned CNT (carbon nanotube) fibers. The CNT fibers were prepared by yarning CNTs grown on the silicone substrate by CVD (chemical vapor deposition) method. The CNT resistors were fabricated by winding CNT fibers on the surface of ceramic rod. Both metal terminals were connected with the CNT fiber wound on the ceramic rod. We measured electrical resistance and thermal stability with the number of CNT fibers wound. The CNT resistor system shows linearly decreased resistance with the number of CNTs wound on the ceramic rod and saturated at 20 strands. The CNT resistor system has negative TCR between $-1,000{\sim}-2,000ppm/^{\circ}C$ and stable frequency properties under 100 kHz.