구개수구개인두성형술 이후의 음성변화

손영익,김선일,윤영선,추광철,정원호 대한후두음성언어의학회 1998 대한후두음성언어의학회지 Vol.9 No.1

Uvulopalatopharyngoplasty(UPPP) is one of the most popular surgical procedure for the treatment of obstructive sleep apnea syndrome(OSAS) occurring at the level of oropharynx. However, voice changes after UPPP have been a challenging issue for the professional voice users, because even minor changes in voice quality or articulation may be critical to professional singers, teachers, and so on. Several acoustic changes after UPPP have been proposed. However, based on the authors understanding, there is no report about voice changes after UPPP in Korean. We measured the first, second and third formant frequencies of /a/, /i/, /u/ phonations in 20 adult male patients who had undergone UPPP surgery, and the nasalances of Rabbit, Baby, and Mama passages. These parameters were measured preoperatively, at 1 month and 3 months after the operation. Any subjective voice changes were asked to be reported at the posto-perative visits. The third formant(F3) of /u/ phonation was significantly reduced at postoperative 1 month measurement. The nasalance of Mama passage was singnificantly increased at postoperative 3 months measurement. No one complained of subjective changes in voice quality, timbre, articulation or speech. Even though there are no complaints about postoperative voice changes subjectively, significant changes in the formant characteristics of certain vowel and changes in the nasality after UPPP require the clinicians to be mort cautious and careful in deciding UPPP for the professional voice users.

A New Approach to Design of a Dynamic Output Feedback Stabilizing Control Law for LTI Systems

손영익,심형보,조남훈,김갑일 대한기계학회 2005 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.19 No.2

We present a new state-space approach to construct a dynamic output feedback controller which stabilizes a class of linear time invariant systems. All the states of the given system are not measurable and only the output is used to design the stabilizing control law. In the design scheme, however, we first assume that the given system can be stabilized by a feedback law composed of the output and its derivatives of a certain order. Beginning with this assumption, we systematically construct a dynamic system which removes the need of the derivatives. The main advantage of the proposed controller is regarding the controller order, which may be smaller than that of conventional output feedback controller. Using a simple numerical example, it is shown that the order of the proposed controller is indeed smaller than that of reduced-order observer based output feedback controller.

e<SUB>ss</SUB>=0: 내부 모델 원리 제어기

손영익,양선직 전력전자학회 2021 전력전자학회지 Vol.26 No.1

변위 정보를 이용한 대형 우주 구조물의 강인 제어기에 관한 연구

손영익 동아대학교 정보기술연구소 2003 情報技術硏究所論文誌 Vol.10 No.2

A robust controller for large space structures(LSS) is studied from passivity point of view. We first show that the robust proportional-derivative (PD) control law for LSS has been designed under the passive property of the system. While velocity sensors are commonly used for PD control law to stabilize large space structures, if the structure can be controlled without velocity measurements, it is desirable against the failure of velocity sensors and for the cost reduction of the sensing system. In a recent result a dynamic output feedback control law has been provided using only displacement measurements. This paper provides an alternative stability analysis tool for the displacement feedback robust control law. The closed-loop system can be viewed as a feedback interconnection of a passive large space structure(LSS) and a strictly passive system. Consequently, the transfer function of the proposed control system has the form of sG(s) where the function G(s) is a transfer function of a strictly passive system.

수지상세포를 이용한 편평세포암종 예방백신

손영익,고예정,정승원,이치규 대한이비인후과학회 2004 대한이비인후과학회지 두경부외과학 Vol.47 No.12

Background and Objectives:Dendritic cells (DC) can effectively mediate the prevention and regression of a variety of solid malignancies when they are properly primed with tumor antigens. However, little has been determined about the efficacy of DCbased vaccine for the prevention of squamous cell carcinoma (SCC). Subjects and Method:Bone marrow derived DC of C3H mouse were pulsed with ultraviolet B-irradiated apoptotic SCCVII cells, which are known as a poorly immunogenic SCC cell line. After vaccinations with those DC, a tumorigenic dosage of healthy SCCVII cells were challenged into the flank of animals and the tumor growth was assessed in a blinded and coded fashion. Results:DC pulsed with apoptotic SCCVII cells effectively prevented the formation of solid tumor in 81% of vaccinated animals and mediated significant retardation of tumor growth (p=0.0029) in 19% of vaccinated animals when compared to control groups. SCCVII cell-specific T-cell response (IFN-γ production) was observed in the immunized mice. Conclusion:Adoptive transfer of DC primed with apoptotic SCCVII cells can serve as an effective preventive vaccine in the poorly immunogenic SCC animal model.

출력의 미분항을 사용하지 않는 적응 관측기 설계 방법

손영익,심형보,백주훈,조남훈 대한전기학회 2004 전기학회논문지 D Vol.53 No.6(D)

By using an adaptive algorithm, together with an additional dynamic system, this paper proposes a new approach to design of a state observer for a class of uncertain systems. We enlarge the class of linear systems from the canonical form of [1] by proposing an adaptive observer that allows unknown parameters to affect those unmeasured states. The result is based on a recent result which presents a design algorithm for an additional system to replace output derivative measurements with the additional dynamics. A numerical example illustrates the design procedure of the state observer.

A Stability Condition on Nominal System Recovery of PMSM Against Mixed Uncertainties Using a Full-Order Load Torque Observer

손영익,장수영 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.5

Since the feedforward compensation using a load torque observer for permanent magnet synchronous motor (PMSM) has been widely used so that an outer feedback loop controller can be designed independently by considering only the nominal plant model, this paper presents an explicit theoretical analysis on the robust performance based on the singular perturbation theory. Unlike the previous result on a reduced-order load torque observer, a stability condition as well as a new coordinate transformation for the boundary-layer system is found out to obtain the desired quasi-steady-state model that equals to the nominal PMSM equation. When the observer gains satisfy the stability condition for the boundary-layer system, as the observer poles are placed sufficiently left of the complex plane, the disturbance observer-based compensation can recover the nominal system characteristics without accounting for model uncertainties that include external disturbances as well as some model parameter uncertainties. Computer simulations verify the disturbance estimation performance against variations of parameters and the disturbance

1차 시스템에 대한 PI 제어기와 PI 관측기 기반 제어기의 전달함수 비교 분석

손영익,장수영,정재국 제어로봇시스템학회 2017 제어로봇시스템학회지 Vol.23 No.4

변위 정보와 SPR 필터를 이용한 대형 우주 구조물의 강인 제어기에 관한 연구

손영익,심형보,조남훈 대한전기학회 2003 전기학회논문지 D Vol.52 No.9(D)

- A robust controller for large space structures(LSS) is studied from passivity point of view. While velocity sensors are commonly used for proportional-derivative (PD) control law to stabilize large space structures, if the structure can be controlled without velocity measurements, it is desirable against the failure of velocity sensors and for the cost reduction of the sensing system. In a recent result a dynamic output feedback control law has been provided using only displacement measurements. This paper presents a passivity-based controller design method and provides an alternative stability analysis tool for the previous displacement feedback robust control law. The closed-loop system can be viewed as a feedback interconnection of a passivated large space structure (LSS) and a strictly positive real (SPR) system.

갑상선과 후두에 발생한 다발성 원발암 1례

손영익,권중근,추광철 대한기관식도과학회 1997 大韓氣管食道科學會誌 Vol.3 No.1

Multiple primary tumors in the head and neck are not uncommon, however those in the thyroid and the larynx are known to be very rare. In most cases of multiple primary tumors involving the thyroid and the larynx, lesions are observed usually simultaneously and thyroid tumors are found incidentally during the laryngeal tumor surgery. In rare cases, thyroid tumors are found metachronously after radiation therapy of laryngeal cancer. The authors recently experienced a case of multiple primary tumor involving the thyroid and the larynx, in which thyroid papillary carcinoma was the index tumor and the laryngeal squamous carcinoma was the meatachronous second tumor. Both tumors showed aggressive local extension and regional nodal meatastasis with tumor collision in the same node. The patient died of recurrent or of residual squamous carcinoma shortly after main surgical treatment index thyroid cancer.