• 제목/요약/키워드: max-min control

검색결과 231건 처리시간 0.03초

Statistic Microwave Path Loss Modeling in Urban Line-of-Sight Area Using Fuzzy Linear Regression

  • Phaiboon, Supachai;Phokharatkul, Pisit;Somkurnpanit, Suripon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.1249-1253
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    • 2005
  • This paper presents a method to model the path loss characteristics in microwave urban line-of-sight (LOS) propagation. We propose new upper- and lower-bound models for the LOS path loss using fuzzy linear regression (FLR). The spread of upper- and lower-bound of FLR depends on max and min value of a sample path loss data while the conventional upper- and lower-bound models, the spread of the bound intervals are fixed and do not depend on the sample path loss data. Comparison of our models to conventional upper- and lower-bound models indicate that improvements in accuracy over the conventional models are achieved.

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Development of an EMG-based Powered Wheelchair Controller for Users with High-level Spinal Cord Injury

  • Han, Jeong-Su;Dimitar H. Stefanov;Lee, Hae-Beom;Kim, Dae-Jin;Song, Won-Kyung;Z. Zenn Bien;Park, Kwang-Hyun;Kim, Jong-sung
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.84.5-84
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    • 2001
  • The objective of this paper is to develop a powered wheelchair controller based on EMG for users with high-level spinal cord injury. EMG is very naturally measured when the user Indicating a certain direction, and the force information which will be used for the speed of wheelchair is easily extracted from EMG. Furthermore, the emergency situation based on EMG will be checked relatively ease. We classified the pre-defined motions such as rest case, forward movement, left movement, and right movement by Fuzzy Min-Max Neural Networks (FMMNN). This classification results shows the feasibility of EMG as an input interface for powered wheelchair. To make the system low cost and small size, we developed EMG AMP and its controller ...

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퍼지 로직을 이용한 ATM 망의 ABR 트래픽 제어 (ABR Traffic Control Using Fuzzy Logic in ATM Networks)

  • 오석용;박동조
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 추계학술대회 학술발표 논문집
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    • pp.105-110
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    • 1998
  • 본 논문에서는 퍼지 로직을 이용하여 ATM 망의 ABR(Available Bit Rate) 트래픽 제어를 위한 효과적이고, 안정적인 피드백 제어 알고리즘을 제안한다. 기존 알고리즘들의 단점을 보완하면서, 망 내의 상황이 변하더라도 자가 학습 기능(self-learning capability)을 이용하여 파라미터 값들을 상황에 맞게 변화시키는 퍼지 로직을 이용한 새로운 제어알고리즘을 제안한다. 제안된 알고리즘은 Projection algorithm을 이용하여, 과거의 데이터로부터 다음 순간의 ABR 버퍼의 크기를 예측하며 퍼지 제어기의 출력 함수 파라미터들은 성능함수를 최소화하도록 학습된다. 제안된 알고리즘은 안정성(stability)이 보장되며, Upstream bottleneck 환경등의 특수하고, 제한된 상태에서도, 요구되는 QoS와 max-min fairness가 만족되고, 링트 효율을 극대화 할 수 있음을 시뮬레이션을 통하여 입증한다.

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Alternating Direction Method를 이용한 최적조류계산의 분산처리 (An Efficient Implementation of Optimal Power Flow using the Alternating Direction Method)

  • 김호웅;박만근;김발호
    • 대한전기학회논문지:전력기술부문A
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    • 제48권11호
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    • pp.1424-1428
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    • 1999
  • This paper presents a mathematical decomposition coordination method to implementing the distributed optimal power flow (OPF), wherein a regional decomposition technique is adopted to parallelize the OPT. The proposed approach is based on the Alternating Direction Method (ADM), a variant of the conventional Augmented Lagrangian approach, and makes it possible the independent regional AC-OPF for each control area while the global optimum for the entire system is assured. This paper is an extension of our previous work based on the auxiliary problem principle (APP). The proposed approach in this paper is a completely new one, however, in that ADM is based on the Proximal Point Algorithm which has long been recognized as one of the attractive methods for convex programming and min-max-convex-concave programming. The proposed method was demonstrated with IEEE 50-Bus system.

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마하-젠더 광 변조기와 EDFA로 구성된 아날로그 광통신 링크에서 변조기 바이어스 조정을 이용한 랜덤 지터의 감소 (Jitter Reduction by Modulator-Bias Control in Analog Fiber-Optic Links Employing a Mach-Zehnder Modulator Followed by an Erbium-Doped Fiber Amplifier)

  • 이민영;윤영민;신종덕
    • 전기전자학회논문지
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    • 제13권4호
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    • pp.103-109
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    • 2009
  • 본 논문에서는 마하-젠더 광 변조기와 EDFA(Erbium-Doped Fiber Amplifier)로 구성된 아날로그 광통신 링크에서 광 변조기에 인가되는 바이어스 전압의 조정을 통해 광통신 링크 출력의 랜덤 지터를 효과적으로 감소시키는 방법에 관하여 연구하였다. 광 변조기의 바이어스를 $0.5\;V_{\pi}$로부터 약 $0.089\;V_{\pi}$로 이동시켰을 때, 10 GHz RF 신호의 이득은 최대 10.65 dB가 증가하였고, 랜덤 지터는 EDFA의 입력 광 파워가 -0.11 dBm일 때 최대 46.5% 감소하였다.

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베라파밀과 퀠세틴의 토끼에서의 약물동태학적 상호작용 (Pharmacokinetic Interaction between Verapamil and Quercetin in Rabbits)

  • 최준식;범진필
    • Journal of Pharmaceutical Investigation
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    • 제34권1호
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    • pp.15-21
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    • 2004
  • The pharmacokinetics of orally administered verapamil (10 mg/kg) was studied in six rabbits after 20 min pretreatment with quercetin ad coadministration of quercetin (2.0 mg/kg, 1 mg/g and 20 mg/kg, respectively). Pretreatment with quercetin significantly (p < 0.01, p < 0.05) increased the plasma concentration of verapamil. However, coadministration of quercetin showed no significantly effect on the pharmacokinetic parameters of verapamil. The elimination rate constant $(K_{el})$ of verapamil pretreated with quercetin (1 mg/kg and 20 mg/kg) was significantly (p < 0.05) reduced compared with control. The area under the plasma concentration-time curve (AUC) and the peak concentration $(C_{max})$ of verapamil pretreated with quercetin (2.0 mg/kg, 10 mg/kg and 20 mg/kg) were increased significantly (p < 0.01, p < 0.05) compared with control. Pretreatment with quercetin (2.0 mg/kg, 10 mg/kg and 20 mg/kg) significantly (p < 0.01, p < 0.05) increased the relative bioavailability of verapamil to 159 - 219%. These results suggest that quercetin alters disposition of verapamil by inhibition of P-glycoprotein efflux pump and its first-pass metabolism. The dosage of verapamil should be adjusted when it is administered chronically with quercetin in a clinical situation.

고등어육 단백질 가열겔 물성에 대한 알카리 전해수세수 효과 (Effects of Electrolytic Alkali Water Washing on Mackerel (Scomber japonicus) Muscle Protein Heat Gel Rheology)

  • 이남걸
    • 한국환경과학회지
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    • 제21권2호
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    • pp.233-240
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    • 2012
  • In this study, the alkiline water washing condition of mackerel(Scomber japonicus) dark meat was investigated to improve processing conditions of red muscle fish meat paste heating gel. Chemical alkaline water(CWM) and electrolytic alkiline water(EWM, pH 12) were used for washing the mackerel raw meat. Washed meats were minced with 2.5% salt and heated at $90^{\circ}C$/15 min to testing texture profile analysis. Moisture of CWM and EWM was increased with both washing times(p<0.05). Crude lipids and protiens were decreased with washing times. Lightness of chemical alkaline water washed mackerel heated paste gel(CWHPG) was higher than electrolytic alkaline water washed mackerel heated paste gel(EWHPG). Redness and yellowness were more decreased than control meats. Jelly strength of CWHPG and EWHPG was not increased more than 2 times wased meat and was increased with protein decrease. Texture profile analysis, max force1 of CWHPG and EWHPG was higher hardeness than the control meat except gel strains. From these results, it could be suggested that electric alkialine water washing is also effective in advance the red meat paste heating gel process of kamaboko industry.

PID 이득 동조를 위한 퍼지 스케줄링 (Fuzzy Scheduling for the PID Gain Tuning)

  • 신위재
    • 한국지능시스템학회논문지
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    • 제15권1호
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    • pp.120-125
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    • 2005
  • 본 논문에서는 PID 제어기의 이득 동조를 위한 퍼지 제어기를 제안한다. 제안한 제어기는 PID 제어기의 크리스퍼 출력 오차를 그대로 사용하지 않는 전단 퍼지화기에서 추론단계는 갖지만 Rule Table은 갖지 않는 특징이 있으며, 출력 소속 함수에 두 변수의 관계와 범위를 이용 도식화된 영역에서 비퍼지화 시킨 비선형 출력값을 PID 계수에 부가하는 새로운 Fuzzy PID 제어기를 제안한다. 여기서 Kp, Kd 계수의 최대, 최소 범위를 설정하여 퍼지추론에 의해 새로운 Kp, Kd 계수론 구한다. Ki 계수는 Ziegler-Nichols 동조 규칙을 사용하여 구하였고, 제안한 제어기는 유압서보모터 제어시스템에 의해 실험하였으며 실험결과 양호한 제어특성을 통해 원하는 결과를 얻을 수 있었다.

$BaTiO_3$계 세라믹 박막의 열처리에 따른 미세구조변화 (Varition Microstructure for Heat treatment of Thin Films $BaTiO_3$ System)

  • 박춘배;송민종;김태완;강도열
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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    • pp.293-295
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    • 1994
  • Barium Titanate ($BaTiO_3$) is one of the few titanateds which is cubic at room temperature. It has the perovskite structure, high dielectric constant (${\varepsilon}_r=300$) and a small temperature coefficient of resistance due to it's Low transition temperature ($Tc=120^{\circ}c$). PTCR (Positive Temperature Coefficient of Resistivity) thermistor in thin film $BaTiO_3$ system was prepared by using radio frequency (13.56MHz) and BC magnetron sputter equipment. Polycrystalline, and surface structure characteristics of the specimens were measured by X-ray diffraction (D-Max3, Rigaku, Japan), SEM(Scanning Electron Microscopy: M. JSM84 01, Japan), respectively. Temperature at below $600^{\circ}C$, $1000^{\circ}C$ to $700^{\circ}C$, and above $1100^{\circ}C$ for spotted $BaTiO_3$ thin films showed the amorphous, degree of crystal growth, and polycrystalline, respectively.

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The Usefulness of Extradural Anterior Clinoidectomy for Low-Lying Posterior Communicating Artery Aneurysms : A Cadaveric Study

  • Hyoung Soo Byoun;Kyu-Sun Choi;Min Kyun Na;Sae Min Kwon;Yong Seok Nam
    • Journal of Korean Neurosurgical Society
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    • 제67권4호
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    • pp.411-417
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    • 2024
  • Objective : To confirm the usefulness of the extradural anterior clinoidectomy during the clipping of a low riding posterior communicating artery (PCoA) aneurysm through cadaver dissection. Methods : Anatomic measurements of 12 adult cadaveric heads (24 sides total) were performed to compare the microsurgical exposure of the PCoA and internal carotid artery (ICA) before and after clinoidectomy. A standard pterional craniotomy and transsylvian approach were performed in all cadavers. The distance from the ICA bifurcation to the origin of PCoA (D1), pre-anterior clinoidectomy distance from the ICA bifurcation to tentorium (D2), post-anterior clinoidectomy distance from the ICA bifurcation to tentorium (D3), pre-anterior clinoidectomy distance from the tentorium to the origin of PCoA (D4) and post-anterior clinoidectomy distance from the tentorium to the origin of PCoA (D5) and the distance of the ICA obtained after anterior clinoidectomy (D6) were measured. We measured the precise thickness of the blade for the Yasargil clip with a digital precision ruler to confirm the usefulness of the extradural anterior clinoidectomy. Results : Twenty-four sites were dissected from 12 cadavers. The age of the cadavers was 79.83±6.25 years. The number of males was the same as the females. The space from the proximal origin of the PCoA to the preclinoid-tentorium (D4) was 1.45±1.08 mm (max, 4.01; min, 0.56). After the clinoidectomy, the space from the proximal origin of the PCoA to the postclinoid-tentorium (D5) was 3.612±1.15 mm (max, 6.14; min, 1.83). The length (D6) of the exposed proximal ICA after the extradural clinoididectomy was 2.17±1.04 mm on the lateral side and 2.16±0.89 mm on the medial side. The thickness of the Yasargil clip blade used during the clipping surgery was 1.35 mm measured with a digital precision ruler. Conclusion : The proximal length obtained by performing an external anterior clinoidectomy is about 2 mm, sufficient for proximal control during PCoA aneurysm surgery, considering the thickness of the aneurysm clips. In a subarachnoid hemorrhage, performing an extradural anterior clinoidectomy could prevent a devastating situation during PCoA aneurysm clipping.