• Journal of Electrical Engineering and Technology
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• 제12권5호
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• pp.1883-1890
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• 2017

Transformers are one of the most precious elements of the electric power system. Stability and reliability of the electric power network mainly depend on the working of the transformer. Leakage reactance of the transformer is one of the important factors and accurate calculation of the leakage reactance is necessary for the transformer designers and electric distributors. Leakage reactance of the transformer depends on the geometry of the transformer. There are many different methods for the calculations of the leakage reactance however mostly are usable when the axial heights of the high voltage and low voltage windings are equal. When the axial heights of high voltage and low voltage windings are asymmetric most of the analytical methods are not reliable. In this study, a new analytical method is introduced for the calculation of the leakage reactance. Fourteen different transformers are investigated in this study and four of them are presented in this paper. The results of the new analytical method are compared with the experimental results. Other analytical and numerical methods are also compared with this new method. Results show that this method is more reliable and accurate as compared to the other analytical methods. The maximum relative error between short-circuit test and proposed method for these fourteen transformers was less than 2.8%.

• Journal of electromagnetic engineering and science
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• 제1권2호
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• pp.176-181
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• 2001

This paper presents the farced resonant characteristics of an electrically small cavity partially filled with dielectric material. The method of moments with Galerkins procedure is used to determine the farced resonant characteristics of the small cavity. In order to obtain the equations of the external reactance gives rise to the farced resonance at a given frequency, the cavity with external reactance can be treated as two-port network which has the admittance parameters. Numerical results show that the forced resonance, series or parallel resonance, can be obtained by the controlling the external reactance. To verify the availability of the theoretical analysis, experiments are carried out for the bakelite as the material by measuring the length of external reactance at operating frequencies.

• 한국보건간호학회지
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• 제35권2호
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• pp.283-296
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• 2021

Purpose: The aim of this study was to investigate the influence of threat perception and psychological reactance to graphic health warnings on cigarette packages on intention to quit smoking among smoking adolescents. Methods: The participants were 185 smoking adolescents attending two industrial specialized high schools, who had witnessed graphic health warnings on cigarette packages within the previous 30 days. Collected data were analyzed using descriptive statistics, the t-test, one-way analysis of variance, Pearson's correlation coefficients, and hierarchical multiple regression analysis using SPSS/WIN Ver. 25.0. Results: The results showed that participant threat perception (𝛽=.14, p=.037) after witnessing a cigarette warning message had a positive influence on intention to quit smoking. On the other hand, psychological reactance (𝛽=-.23, p=.001) showed a negative influence on intention to quit smoking. Conclusion: When designing and developing a message for smoking adolescents, customized messages are required to reflect teenagers' characteristics and raise threat perception and lower psychological reactance. In addition, we propose a future study be conducted to determine the influences of various psychological determinants, including self-efficacy and skills, on threat perception and psychological reactance to graphic health warnings on cigarette packages among smoking adolescents.

• 대한전자공학회논문지
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• 제11권6호
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• pp.44-49
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• 1974

종래부터 사용되어 오고 있는 Reactance 변조방식에 가변 Reactance 소자로 VVC Diode를 다단으로 사용한 위상변조방식과 수정발진자와 λ/4 결합회로를 통하여 VVC Diode를 사용한 수정주파수변조 방식을 간단히 소개하고 실용적인 관점에서 FM 변조기로서의 제반특성을 두가지 변조방식에서 상호비교하였다. 특히 VVC Diode를 사용한 Reactance 변조방식에 있어서 변조감도를 높이기 위하여 다단변조를 하였을 때의 발생하는 고조파련에 관하여 상세히 고찰하여 본 결과 중심주파수의 안정도가 -40℃까지의 넓은 온도 범위에 걸쳐서 요구될 때는 다단위상변조방식을 택하여 변조도가 깊지 않는데서 체배하여서 소요의 편이를 얻는 것이 좋다는 것을 확인하여서 이를 차륜용무전기에 실용화하였다. 한편 VVC Dicde를 사용한 수정각파수변조기는 -20℃까지의 중심주파수 안정도를 요하나 변조감도가 높고 소형으로 유리하다는 점에서 휴대용무전기에 실용화하여서 좋은 결과를 얻었다.

• 한국의류산업학회지
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• 제17권5호
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• pp.770-780
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• 2015

This study intended to explore fundamental causes affecting consumers' response actions from psychological factors in the situation of sellout occurring during shopping in online fashion stores. In addition, this study devised a virtual online shop in order to measure consumers' cognitive and emotional psychological responses they experienced when goods were sold out. The subjects involved women in 20s~30s, major customers of online shopping, and the subjects were randomly allocated to one of eight questionnaire forms (2(stockout size: high vs low)${\times}2$(product assortment similarity: similar vs. dissimilar)${\times}2$(restocking cue: included vs excluded)). The number of final data used for the analysis was 336 and through SPSS 21.0 program, two-way ANOVA and bootstrap were utilized. The analysis result was that consumers' psychological responses (emotions, psychological reactance) of online shops differed by means of varying stockout situations. The stockout size had positive effect on psychological reactance and negative emotions. On the other hand, there was no difference in positive emotions (arousal) according to stockout size. In stockout situation of online fashion store, the moderating effect of product assortment similarity and restocking cues were verified. According to the analysis result, interaction effects between stockout size and restocking cues, product stockout size and product assortment for psychological reactance were significant. Lastly, the mediation effect of psychological reactance and emotion between stockout size and behavioral response was tested. As a result, the moderated mediation effects of psychological reactance for substitute were significant when product assortment was dissimilar and restocking cue was exclude.

• 한국산학기술학회논문지
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• 제14권6호
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• pp.2707-2716
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• 2013

본 연구는 다양한 형태의 조직들에서 IT 거버넌스와 관련된 통제에 대해 조직원들의 개인기기 사용 확산에 따른 반발 심리의 분석에 초점을 둔다. 이를 위해 IT 거버넌스 통제와 관련된 선행 연구, 조직원의 반발 심리에 대한 척도 및 기대이론을 바탕으로 연구 모형을 구성하였다. Hong의 심리적 반발 척도, 기대이론의 보상 정도, 조직에서의 직급이나 조직 규모에 따라 조직원들의 IT 통제에 대한 반발요인과 태도의 통계적 유의성을 검증할 수 있었다. 이를 통해 IT 거버넌스를 통한 경영목표 달성을 위한 통제와 조직원 반발요인에 대한 체계적 분석을 통한 분석 틀을 제시하고 실무적으로도 조직의 IT 거버넌스 통제에 대한 시사점을 얻을 수 있다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.184-184
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• 2012

We proposed a new measurement method of cutoff probe using the reactance spectrum of the plasma in cutoff probe system instead of transmission spectrum. The high accurate reactance spectrum of the plasma which is expected in previous circuit simulation of cutoff probe [1] was measured by using the automatic port extension method of the network analyzer. The measured reactance spectrum is good agreement with E/M wave simulation result (CST Microwave Studio). From the analysis of the measured reactance spectrum based on the circuit modeling, not only the electron density but also electron-neutral collision frequency can be simply obtained. The obtained results of electron density and e-n collision frequency were presented and discussed in wide range of experimental conditions, together with comparison result with previous methods (a previous cutoff probe using transmission spectrum and a single langmuir probe).

• ETRI Journal
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• 제41권6호
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• pp.715-730
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• 2019

We propose a switched beam-forming antenna that satisfies not only ultra-wideband characteristics but also beam-forming in the WLAN frequency band using an ultra-wideband antenna and passive parasitic elements applying a broadband optimal reactance load algorithm. We design a power and phase estimation function and an error correction function by re-analyzing and normalizing all the components of the parasitic array using control system engineering. The proposed antenna is compared with an antenna with a pin diode and reactance load value, respectively. The pin diode is located between the passive parasitic elements and ground plane. An antenna beam can be formed in eight directions according to the pin diode ON (reflector)/OFF (director) state. The antenna with a reactance load value achieves a better VSWR and gain than the antenna with a pin diode. We confirm that a beam is formed in eight directions owing to the RF switch operation, and the measured peak gain is 7 dBi at 2.45 GHz and 10 dBi at 5.8 GHz.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.405-408
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• 2000

We designed and fabricated VCO using inductive reactance variation at 2GHz. A varactor diode is one of the main devices in VCO, which varies capacitance depending on reverse voltage. In this paper, a varactor diode is not used as a variable capacitive reactance device but as an inductive device. The circuit design and simulation have been carried out using HP-MDS. The fabricated VCO is measured using the HP 8532B spectrum analyzer and the HP 4352B VCO/PLL analyzer. The experimental result shows the phase noise -110dBc/Hz at a 100kHz offset frequency, the control voltage sensitivity of 23MHz/V and a -3.5dBm output power with a D.C. current consumption of 5.9mA. The simulation and measurements show exact agreement except with regard to the oscillation frequency. The measured oscillation frequency is lower than the simulation result because there is some parasitic inductance in the PCB layout.

• 대한전기학회논문지
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• 제39권12호
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• pp.1317-1320
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• 1990

The inductive reactance losses of a superconducting current generator built at Case Western Reserve University has been analyzed. The calculations of the field in the spot make it possible to estimate the spot inductance as well as the filament inductance on the foil. It is shown that magnetic energy lost in switching the current is mainly due to the amplitude of the fluctuation in voltage associated with the inductive reactance losses of a superconducting current generator.