• 대한기계학회논문집
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• 제19권1호
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• pp.271-276
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• 1995

This paper presents a systematic method for the dynamic analysis of flexible mechanical systems containing closed kinematic loops. Kinematics between pairs of contiguous flexible bodies is described with the joint coordinates and the deformation modal coordinates. The cut-joint constraint equations associated with the closed kinematic loops are derived, simply using the geometric conditions. The equations of motions are initially written in terms of the joint and modal coordinates using the velocity transformation technique. Lagrange multipliers associated with the cut-joint constraints for closed-loop systems are then eliminated systematically using the generalized coordinate partitioning method, resulting to a minimal set of equations of motion.

• 제어로봇시스템학회논문지
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• 제19권7호
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• pp.583-586
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• 2013

We consider discrete-time LTI (Linear Time-Invariant) systems with constant input delays. The input delay is modeled by a first-order PdE (Partial difference Equation) and a backstepping transformation is employed to design a predictor feedback controller. The backstepping approach results in the construction of an explicit Lyapunov function, with which we prove the exponential stability of the closed-loop system formed by the predictor feedback. The numerical example demonstrates the design of the predictor feedback controller, and illustrates the validity of the exponential stability.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 B
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• pp.696-698
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• 1997

The marine diesel engine have been widely applied with a mechanical hydraulic governor to control the ship speed for long time. But it was recently very difficult for the mechanical hydraulic governor to control the speed of engine under the condition of low speed and low load because of jiggling by rough fluctuation of rotating torque and hunting by dead time of diesel engine. In order to analyze the speed control system the transfer function was converted from z to w transformation. The author proposed velocity control system with feedback loop by PID controller in order to stabilize for unstable area. The influence of dead time was discussed by Nichols chart and unit step response curve. It was confirmed through computer simulation that the performance improvement of a mechanical hydraulic governor can be obtained by PID controller.

• 수산해양기술연구
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• 제25권3호
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• pp.137-142
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• 1989

본 논문에서는 연속시간계의 설계 문제에 있어, 연속계의 설계방법 그대로서는 설계 불가능한 하나의 문제, 즉, 복소좌반 평면상의 어떤 지정한 폐영역내의 극배치 문제를 쌍선형변환법을 이용해서 해결하는 하나의 설계방법을 제안했다. 실제적인 시스템 설계의 경우, 폐루우프 계의 특성근을 정확히 지정된 위치에 배치하여야만 할 경우는 드물고, 대개의 경우, 어떤 희망하는 영역내에 배치하면 충분하다. 특히 구체적으로 극을 지정하는 지침에 결핍되어 있을 경우나, 폐루우푸 계의 특성인 속응성, 진동특성, 안정도 등을 고려할 경우, 그 극을 지정 위치에 배치하기보다도 어떤 지정한 영역내에 배치하는 쪽이 유효하다고 할 수 있으므로, 다변수제어계의 설계 문제에 있어, 그 가치가 크다고 할 수 있다

• Corrosion Science and Technology
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• 제19권3호
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• pp.146-155
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• 2020

To elucidate the effect of heat inputs on phase transformation and resistance to intergranular corrosion of F316 austenitic stainless steel (ASS), thermodynamic calculations of each phase and time-temperature-transformation diagram were conducted using JMaPro simulation software, oxalic acid etch test, double-loop electrochemical potentiokinetic reactivation test (DL-EPR), field emission scanning electron microscopy with energy dispersive spectroscopy, and transmission electron microscopy analyses of Cr carbide (Cr₂₃C₆), austenite phase and ferrite phase. F316 ASS containing a relatively low C content of 0.043 wt% showed a slightly sensitized microstructure (acceptably dual structure) due to a small amount of Cr carbide precipitated at heat affected zone irrespective of heat inputs. Based on results of DL-EPR test, although heat input was increased, the ratio of I_r to I_a was only increased very slightly due to a slight sensitization. Therefore, heat inputs have little influences on resistance to intergranular corrosion of F316 austenitic stainless steel containing 0.043 wt% C.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 V
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• pp.2827-2830
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• 2003

Tele manipulator is distingushed from industrial robot by iterating same specified work. Manipulator operator is included in control loop for controlling the telemanipulator because he decide directly during the work and order controllabily reducing the modelling error of telemanipulator which depend on the PID controller. But position-force control method of bidirectional control impose unsafety of vibiration and Analytic Hierachy Method can stabilize for reducing nonlinear modelling error by expert operator because of transformation empirical control rule to linear model.

• 전자통신동향분석
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• 제9권4호
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• pp.9-21
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• 1994

Wide variety of the architectural complexity of parallel computer often makes it difficult to develop efficient programs for them. One of approaches to improve this difficulty is to program in familiar sequential languages such as Fortran or C and to parallelize sequential programs into equivalent parallel programs automatically. This paper presents an organization of parallelizing compiler which transforms sequential programs into equivalent parallel programs. The parallelizer consists mainly of syntax analysis, control and data flow analysis, program transformation, and parallel code generation. In particular, the program restructuring in this parallelizer maximizes loop parallelism.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2004년도 봄 학술발표논문집 Vol.31 No.1 (B)
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• pp.850-852
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• 2004

고급 언어 (high-level language)로 프로그램을 쓰고 그것이 맞다고 증명 했을때, 프로그램과 증명을 동시에 "컴파일"해주는 방법을 찾으려고 한다. 이러한 방법은 "증명 보내기"(Proof Carrying Code)라는 제안을 실용화할 때 요긴하게 사용할 수 있는 기술이다. 지면관계상 "반복문에서 명령어 끄집어내기"(Loop Invariant Code Motion)라는 최적화 과정에 맞게 Hoare 증명을 변환하는 방법에 대해서만 알아보겠다.

• International Journal of Advanced Culture Technology
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• 제9권4호
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• pp.282-287
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• 2021

A multicore system must be able to take full advantage of the program's instruction and data parallelism. This study introduces the data replication technique as a support technique to maximize the program's instruction and data parallelism. Instruction level parallelism can be limited by data dependency. In this case, if data is replicated to each processor core and used, instruction level parallelism can be used to the maximum. The technique proposed in this study can maximize the performance improvement effect when applied to scientific applications such as matrix multiplication operation.

• Asian Pacific Journal of Cancer Prevention
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• 제17권6호
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• pp.2853-2856
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• 2016

Background: Many studies have pointed to strategies to cope with patient anxiety in colposcopy. Evidence shows that patients experienced considerable distress with the large loop excision of transformation zone (LLETZ) procedure and suitable interventions should be introduced to reduce anxiety. This study aimed to investigate the effects of music therapy in patients undergoing LLETZ. Materials and Methods: A randomized controlled trial was conducted with patients undergoing LLETZ performed under local anesthesia in an out patient setting at Ramathibodi Hospital, Bangkok, Thailand, from February 2015 to January 2016. After informed consent and demographic data were obtained, we assessed the anxiety level using State Anxiety Inventory pre and post procedures. Music group patients listened to classical songs through headphones, while the control group received the standard care. Pain score was evaluated with a visual analog scale (VAS). Statistical analysis was conducted using Pearson Chi-square, Fisher's Exact test and T-Test and p-values less than 0.05 were considered statistically significant. Results: A total of 73 patients were enrolled and randomized, resulting in 36 women in the music group and 37 women in the non-music control group. The preoperative mean anxiety score was higher in the music group (46.8 VS 45.8 points). The postoperative mean anxiety scores in the music and the non-music groups were 38.7 and 41.3 points, respectively. VAS was lower in music group (2.55 VS 3.33). The percent change of anxiety was greater in the music group, although there was no significant difference between two groups. Conclusions: Music therapy did not significantly reduce anxiety in patients undergoing the LLETZ procedure. However, different interventions should be developed to ease the patients' apprehension during this procedure.