• Journal of Electrical Engineering and Technology
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• v.13 no.2
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• pp.769-780
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• 2018

This paper presents an analysis of the power gain under partial shading conditions (PSC) when the partial shade loss is being compensated in photovoltaic(PV) system. To analyze the power gain, our study divides the mismatch loss into partial shade loss and operating point loss. Partial shade loss is defined as the power difference between a normal string and a partially shaded string at the maximum power point (MPP). Operating point loss is defined as the power loss due to the operating point shift while following the MPP of the PV array. Partial shading in a PV system affects the maximum power point tracking (MPPT) control by creating multiple MPPs, which causes mismatch losses. Several MPPT algorithms have been suggested to solve the multiple MPP problems. Among these, mismatch compensation algorithms require additional power to compensate for the mismatch loss; however, these algorithms do not consider the gain or loss between the input power required for compensation and the increased output power obtained after compensation. This paper analyzes the power gain resulting from the partial shade loss compensation under PSC, using the V-P curve of the PV system, and verifies that power gain existence by simulation and experiment.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.223-226
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• 2004

This paper analyzes the accuracy of free space path loss and matched filter gain approximated by using a passband rectangular pulse for ultra wideband (UWB) radio systems. The example causal signal, a modulated Gaussian pulse with the same center frequency and frequency bandwidth of the passband rectangular pulse, is used to consider the accuracy. The path loss and matched filter gain of the modulated Gaussian pulse are simulated for the reference results. The UWB free space path loss is shown and is compared with that obtained from simulation and Friis' transmission formula. The UWB matched filter gain is shown and compared with simulation results. From the results, we can see that the UWB path loss formula is more accurate than the Friis' transmission formula. The results from the UWB free space path loss and matched filter gain formulas agree with the simulation. Then, these free space path loss and matched filter gain formulas approximated by using a passband rectangular pulse are appropriate for UWB system.

• Korean Journal of Social Welfare
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• v.65 no.2
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• pp.335-356
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• 2013

Physical resources are central to coping with economic hardships for people in low-income, yet life experiences such as resource loss and gain and their relationships with a sense of well-being received scarce attention. Thus this study investigated levels of loss and gain of physical resources, economic stability and well-being of 254 adults who participated in welfare-to-work programs; correlations and paths among these variables; and direct and indirect effects of economic stability by structural equation modeling. Major results were: first, the levels of resource loss and gain were below a moderate level and the level of gain was significantly higher than the loss level. Second, in the relationships with both economic stability and well-being, resource loss showed negative correlations, while resource gain showed significantly positive correlations. Third, the negative direct effect of resource loss either on the economic stability or on the well-being respectively was significant and the indirect effect on well-being through economic stability was also significant. Finally, the direct effect of resource gain on either economic stability or well-being was significant; and the indirect effect of resource gain on well-being was also significant. Thus in both models for resource loss and gain, the indirect effect of economic stability was significant, which supports partial mediation model. Based on these results, implications for social work practice and research were examined, particularly for enabling social work practice to utilize information regarding resource loss and gain, economic stability, and a sense of well-being that were embedded in the community life of people in low-income.

• Journal of the Korea Society of Computer and Information
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• v.24 no.1
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• pp.231-238
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• 2019

The objective of this study is to understand the relationship between type of advertising and brand attachment. We divide advertising frame into loss and gain frame and examine the effect on brand attachment, The effect of unique advertising on brand attachment and the effects of interaction effects on brand attachment were examined. The results showed that the effect of the loss and gain frame on brand attachment was statistically significant. It also showed that unique advertising had positive effect on brand attachment. Moreover, the interaction effects of the advertising frame and the uniqueness of advertising have been shown to affect brand attachment. That is, the more emphasis on gain in advertising frame and the more unique advertising, the more effective on brand attachment.

• Korean Journal of Optics and Photonics
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• v.18 no.2
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• pp.93-99
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• 2007

We investigated analytically and numerically the occurrence of modulation instability in fibers with periodic changes both in dispersion and gain. Previously, it has been known that the modulation instability is suppressed in dispersion managed solitons where dispersion is managed in such a way that the local dispersion alternates between the normal and the anomalous regimes. In this work, we enhanced the advantage of the dispersion management scheme by additionally introducing proper gain/loss profiles in fibers. The gain/loss profile is given by $\Gamma(z)=0.5/D(z)*(dD/dz)$, where D(z) represents the dispersion profile. The fundamental gain spectra of the modulation instability in the dispersion and gain managed fibers have been derived analytically and confirmed by numerical calculation. Our investigation reveals that in the dispersion and gain fibers the modulation instabilities are always much more suppressed compared to the case with only dispersion managed. In practical dispersion management schemes, dispersion profiles show discontinuity. and thus. the corresponding gain/loss profiles tend to be finite. In these cases, the gain/loss profiles were approximated by lumped gains/losses of finite values. Our numerical calculations confirm that this approximation also works well.

• Journal of Audiology & Otology
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• v.24 no.3
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• pp.127-132
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• 2020

Background and Objectives: In this study, we compared the outcomes of patients with idiopathic sudden sensorineural hearing loss who underwent steroid treatment with or without hyperbaric oxygen (HBO) therapy and were followed-up in our clinic. Subjects and Methods: Patients were divided into two groups according to their treatment regimen. Steroid group received intravenous 1 mg/kg methylprednisolone which was due to be completed in 2-3 weeks with decreasing doses, and five doses of 0.5 mL intratympanic dexamethasone. Steroid+HBO group received the same steroid treatment with the addition of HBO therapy. The audiologic results of both treatment groups were compared after considering the patients' risk factors. Results: There was no significant difference between the steroid and Steroid+HBO groups in terms of hearing gain and degree of recovery, both at all degrees of hearing loss, and in severe and profound hearing loss. Hearing gain was similar when evaluated by audiogram type and admission time in both treatment groups. Conclusions: We found that the addition of HBO therapy to systemic plus intratympanic steroid treatment did not affect hearing gain at all degrees of hearing loss in this study. Furthermore, audiogram type and admission time did not affect hearing gain between the two groups.

• Korean Journal of Audiology
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• v.24 no.3
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• pp.127-132
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• 2020

Background and Objectives: In this study, we compared the outcomes of patients with idiopathic sudden sensorineural hearing loss who underwent steroid treatment with or without hyperbaric oxygen (HBO) therapy and were followed-up in our clinic. Subjects and Methods: Patients were divided into two groups according to their treatment regimen. Steroid group received intravenous 1 mg/kg methylprednisolone which was due to be completed in 2-3 weeks with decreasing doses, and five doses of 0.5 mL intratympanic dexamethasone. Steroid+HBO group received the same steroid treatment with the addition of HBO therapy. The audiologic results of both treatment groups were compared after considering the patients' risk factors. Results: There was no significant difference between the steroid and Steroid+HBO groups in terms of hearing gain and degree of recovery, both at all degrees of hearing loss, and in severe and profound hearing loss. Hearing gain was similar when evaluated by audiogram type and admission time in both treatment groups. Conclusions: We found that the addition of HBO therapy to systemic plus intratympanic steroid treatment did not affect hearing gain at all degrees of hearing loss in this study. Furthermore, audiogram type and admission time did not affect hearing gain between the two groups.

• Asia-Pacific Journal of Business
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• v.11 no.4
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• pp.65-81
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• 2020

Purpose - This research aims to investigate how consumers' eco-friendly product choice ratio changes as the benefits of eco-friendly products are framed as (1) non-monetary benefits, (2) monetary gain integrated with the loss or (3) monetary gain segregated from the loss. Design/methodology/approach - A mixed-design, scenario-based choice experiment was conducted. A series of chi-square tests and residual analyses were conducted to analyze the data. Findings - When the monetary gain was larger or slightly smaller than the loss, the participants' eco-friendly product choice ratio was higher when the monetary gain was integrated with the loss than those in the other two conditions. When the monetary gain was significantly smaller than the loss, the participants' eco-friendly product choice ratio was lower when the monetary gain was integrated with the loss than those in the other conditions. The ratio did not differ between the latter two conditions. Research implications or Originality - This research shows that marketers should frame the benefits of eco-friendly products and their costs in different manners depending on the relative magnitudes of them. This research also complements the existing literature by comparing the effectiveness of non-monetary framing of eco-friendly product benefits with that of monetary framing following hedonic editing hypothesis.

• The Plant Pathology Journal
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• v.19 no.6
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• pp.301-304
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• 2003

Gamma-ray irradiation is known to induce various mutations in plants caused by chromosome alterations. This study investigated disease responses of selected gamma-ray induced rice mutants generated from seven Japonica-type rice cultivars against three plant diseases. Among the tested 22 mutants, three gain-of-function mutants and six loss-of-function mutants against rice blast were obtained, as well as three loss-of-function mutants against bacterial leaf blight (BLB). Two of the loss-of-function mutants were susceptible to both rice blast and BLB. Gain-of-function mutation has not been frequently observed in rice plants, thus, the mutants can be used to identify loci of novel genes for the regulation of disease resistant response.

• Journal of the Optical Society of Korea
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• v.12 no.4
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• pp.303-308
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• 2008

Directly modulated fiber-optic links generally suffer higher link loss and larger signal distortion than externally modulated links. These result from the electron-photon conversion loss and laser modulation dynamics. As a method to overcome the drawbacks, we have experimentally demonstrated the RF performance of directly modulated, ultra-strong injection-locked gain-lever distributed Bragg reflector (DBR) lasers. The free-running DBR lasers exhibit an improved amplitude modulation efficiency of 12.4 dB under gain-lever modulation at the expense of linearity. By combining gain-lever modulation with ultra-strong optical injection locking, we can gain the benefits of both improved modulation efficiency from the gain-lever effect, plus improved linearity from injection locking. Using an injection ratio of R=11 dB, a 23.4-dB improvement in amplitude response and an 18-dB improvement in spurious-free dynamic range have been achieved.