Earticle

Structural controllability is an important concept of linear systems, and problems relating to this concept have recently become the subject of a great deal of research. In this paper, two different structures of control are proposed that are based on the servo control system. An analysis is conducted on the structural controllability of two control systems, the differences of which relate to the structural controllability criterion in the frequency domain over F(z). Due to the fact that the system is not structurally controllable, the first servo control system is not completely manageable no matter what values the parameters take; therefore, the reasons for this are investigated. Conversely, the second system becomes structurally controllable by changing the structure of the control system. Thus, it is made fully stable by the feedback compensation even if it has an unstable mode. Accordingly, this research on the structural controllability of a system not only provides a deeper understanding of the system’s nature, but is also important for explaining why a system is not structurally controllable and how changing its structure can resolve this.

The control of Ga doping in ZnO nanowires (NWs) by physical vapor deposition has been implemented and characterized. Various Ga-doped ZnO NWs were grown using the vapor-liquid-solid (VLS) method, with Au catalyst on c-plane sapphire substrate by hot-walled pulsed laser deposition (HW-PLD), one of the physical vapor deposition methods. The structural, optical and electrical properties of Ga-doped ZnO NWs have been systematically analyzed, by changing Ga concentration in ZnO NWs. We observed stacking faults and different crystalline directions caused by increasing Ga concentration in ZnO NWs, using SEM and HR-TEM. A $D^0X$ peak in the PL spectra of Ga doped ZnO NWs that is sharper than that of pure ZnO NWs has been clearly observed, which indicated the substitution of Ga for Zn. The electrical properties of controlled Ga-doped ZnO NWs have been measured, and show that the conductance of ZnO NWs increased up to 3 wt% Ga doping. However, the conductance of 5 wt% Ga doped ZnO NWs decreased, because the mean free path was decreased, according to the increase of carrier concentration. This control of the structural, optical and electrical properties of ZnO NWs by doping, could provide the possibility of the fabrication of various nanowire based electronic devices, such as nano-FETs, nano-inverters, nano-logic circuits and customized nano-sensors.

본 연구의 목적은 서비스를 제공받는 과정에서 서비스실패를 경험한 고객을 대상으로 공정성 차원(분배, 절차, 상호작용 및 정보공정성), 회복만족, 신뢰 및 전환의도 간의 상호 관련성을 검증하고자 하는 것이다. 또한 공정성 차원과 회복만족 간의 관계에서 통제성의 조절효과를 검증하고자 하는 것이다. 자료 수집은 서비스실패에 따른 회복 경험이 있는 고객을 대상으로 하여 직접대면을 통해 설문지 수집하여 463부를 최종 분석에 이용하였고, 표본추출방법은 편의표본 추출방법을 이용하였다. 그리고 척도정제를 위해 신뢰도, 탐색적 요인분석과 확인적 요인분석을 실시하였으며, 가설검증은 AMOS를 이용하였다. 경로분석에 의한 본 연구의 결과, 공정성 차원(분배, 절차, 상호작용 및 정보공정성)은 모두 회복만족에 정의 영향을, 회복만족은 신뢰에 정의 영향을, 그리고 회복만족과 신뢰는 전환의도에 부의 영향을 미치는 것으로 나타났다. 그리고 공정성 차원과 회복만족 간의 관계에서 분배공정성에서만 통제성의 조절효과를 가지는 것으로 나타났다. 마지막으로 본 연구는 이런 조사결과를 바탕으로 이론적 및 실무적 시사점을, 그리고 한계점에 따른 미래 연구방향을 제시하고 있다.

The objectives of this study are to analyze the interrelationship among justice dimensions, recovery satisfaction, trust and switching intention, and to investigate the moderating effect of controllability between justice dimensions (distributional, procedural, interactional, and informational justice) and recovery satisfaction based on the customers who have experienced service failures and recovery. After eliminating unusable questionnaires due to significant omissions, a total of 463 questionnaires were usable. And convenience sampling is used. To purify the scale, reliability test, exploratory and confirmatory factor analysis were conducted using data, and hypothesis testing was performed using AMOS. The results show that all justice dimensions(distributional, procedural, interactional, and informational justice) have a positive influence on recovery satisfaction. Recovery satisfaction has a positive effect on trust, and recovery satisfaction and trust have a negative influence on switching intention. Also controllability has only moderating effect in relationship between distributional justice and recovery satisfaction. Finally, this study suggests the implications of these findings, both theoretically and practically, and also offers directions for future research.