• Title/Summary/Keyword: Poor stability

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Fillers for Solid-State Polymer Electrolytes: Highlight

  • Jung, Srun;Kim, Dae-Won;Lee, Sang-Deuk;Cheong, Minserk Cheong;Nguyen, Dinh Quan;Cho, Byung-Won;Kim, Hoon-Sik
    • Bulletin of the Korean Chemical Society
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    • v.30 no.10
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    • pp.2355-2361
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    • 2009
  • The current solid polymer electrolytes suffer from poor conductivity, low mechanical and electrochemical stability toward the lithium electrodes. To improve the performance of solid polymer electrolytes, the addition of nanoparticle fillers to the polymer electrolyte is being extensively investigated. In this paper, a brief review on the state of art of solid fillers for lithium battery electrolytes is presented.

Combination-mode BLE Device Profile for Connection & Non-connection Methods

  • Jiang, Guangqiu;Joe, Inwhee
    • Proceedings of the Korea Information Processing Society Conference
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    • 2016.04a
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    • pp.897-899
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    • 2016
  • In recent years, BLE technology has received extensive attention and has been applied to all aspects of life. The existing BLE device has two methods, one is the connection method, and the other is a non-connection method. The representative profile of the connection method is the proximity file. The most typical example of Non-connection method BLE device is a beacon. However, they are both independent and have their own shortcomings. Connection method device can provide service for only one user, others can't use. Security performance of Non-connection method BLE device is poor and the device can't be controlled by the user. In this paper, a combination-mode BLE device profile design scheme is presented, which combines with the previous two methods, and solves the defaults. And We define a dual purpose advertising package that can be used in a normal environment as well as in a disaster environment. Finally, a unidirectional Control idea is proposed. Through performance evaluation, we found that the device has strong stability and low power consumption.

Robust Real-Time Wireless Control Platform Compensating for Packet Loss (패킷 손실에 강인한 원격 실시간 무선제어 플랫폼)

  • Choi, Rock-Hyun;Lee, Sang-Cheol;Yoo, Joon-Hyuk
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.8
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    • pp.768-773
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    • 2012
  • Packet loss compensation techniques are increasingly important to stable remote control over wireless communication in WNCS (Wireless Networked Control Systems). Its time varying channels, limited bandwidth, interference, and poor signal not only leads to packet loss or latency, but also can negatively affect performance and system stability. This paper presents a compensation technique exploiting an EWMA (Exponentially Weighed Moving Average)-based value estimator to clarify the influence of packet loss on the overall WNCS behavior. As an example of actuator to be remotely controlled, a rotary-type inverted pendulum has been considered, and modeled. Performance evaluation results through Matlab/Simulink and Truetime co-simulation confirm the superiority of the proposed value estimation method over previous approaches.

ORTHOPEDIC AND SURGICO-ORTHODONTIC TREATMENT IN THE LONG FACE (Long Face(open-bite) 환자의 수술 교정 치료)

  • Baik, Hyoung Seon
    • The korean journal of orthodontics
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    • v.19 no.3
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    • pp.147-160
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    • 1989
  • Long face patients are characterized by excessive anterior facial height, lip incompetence at rest, anterior open bite, and gummy smile. A major problem is an inferior rotation of the posterior maxilla and upper molars. Long face patients have been the most difficult for orthodontist to treat successfully. In growing patients, the methods for impeding excessive vertical growth have been used high pull head gear, functional appliance, and combined type of two. One significant improvement comes from using a full arch splint to deliver force to the maxilla more vertically. In adult patients, orthodontic camouflage treatment is biomechanically difficult and doesn't work when the problem is primarilly vertical. Surgical maxillary impaction provides a means for successfully treating most of problems. Also, superior reposition of the chin via a mandibular inferior border osteotomy is effective in decrease of lower anterior facial height and correction of the poor chin-lip balance. Post-surgical stability and the physiologic response are good. The coordinated orthodontic and surgical treatment is necessary for solution the difficult skeletal deformity.

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Ridge augmentation in implant dentistry

  • Kim, Young-Kyun;Ku, Jeong-Kui
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.46 no.3
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    • pp.211-217
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    • 2020
  • In patients with insufficient bone height and width, the successful placement of dental implants is difficult with regards to maintaining an ideal pathway and avoiding important anatomical structures. Vertical and/or horizontal ridge augmentation may be necessary using various bone substitute materials and bone graft procedures. However, effective one-wall reconstruction has been challenging due to its poor blood supply and insufficient graft stability. In this paper, the authors summarize current evidence-based literature based on the author's clinical experience. Regarding bone substitutes, it is advantageous for clinicians to select the types of bone substitutes including autogenous bone. The most important consideration is to minimize complications through principle-based ridge augmentation surgery. Ridge augmentation should be decided with complete consent of the patients due to the possible disadvantages of surgery, complications, and unpredictable prognosis.

Bilateral Control Algorithm for Heavy-Duty Power Manipulators (고하중 매니퓰레이터의 양방향 제어 알고리즘)

  • Ahn, Sung-Ho;Park, Byung-Suk;Kim, Sung-Hyun;Lee, Jong-Youl;Yoon, Ji-Sup
    • Proceedings of the KIEE Conference
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    • 2001.07d
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    • pp.2414-2416
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    • 2001
  • When a heavy-duty power manipulator with high reduction ratio joints is used as telemanipulator in teleoperated systems, its control inputs are frequently saturated resulting in deteriorated stability and poor position tracking performance. This paper proposes a bilateral control algorithm for 3-DOF heavy-duty power manipulators, which compensates for saturation. The proposed bilateral control algorithm provides precise position control performance regardless of saturation.

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Catalytic Effects of Barium Carbonate on the Anodic Performance of Solid Oxide Fuel Cells

  • Yoon, Sung-Eun;Ahn, Jae-Yeong;Park, Jong-Sung
    • Journal of the Korean Ceramic Society
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    • v.52 no.5
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    • pp.350-355
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    • 2015
  • To develop ceramic composite anodes of solid oxide fuel cells without metal catalysts, a small amount of barium carbonate was added to an $(La_{0.8}Sr_{0.2})(Cr_{0.5}Mn_{0.5})O_3(LSCM)$ - YSZ ceramic composite anode and its catalytic effects on the electrode performance were investigated. A barium precursor solution with citric acid was used to synthesize the barium carbonate during ignition, while a barium precursor solution without citric acid was used to create hydrated barium hydroxide. The addition of barium carbonate to the ceramic composite anode caused stable fuel cell performance at 1073 K; this performance was higher than that of a fuel cell with $CeO_2$ catalyst; however, the addition of hydrated barium hydroxide to the ceramic composite anode caused poor stability of the fuel cell performance.

Blastability Quality System (BQS) for using it, in bedrock excavation

  • Christaras, B.;Chatziangelou, M.
    • Structural Engineering and Mechanics
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    • v.51 no.5
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    • pp.823-845
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    • 2014
  • Success in the excavation of foundations is commonly known as being very important in asserting stability. Furthermore, when the subjected formation is rocky and the use of explores is required, the demands of successful blasting are multiplied. The quick and correct estimation of excavation's characteristics may help the design of building structures, increasing their safety. The present paper proposes a new classification system which connects blastability and rock mass quality. This new system primarily concerns poor and friable rock mass, heavily broken with mixture of angular and rounded rock pieces. However, it should concern medium and good quality rock mass. The Blastability Quality System (BQS) can be an easy and widely - used tool as it is a quick calculator for blastability index (BI) and rock mass quality. Taking into account the research calculations and the parameters of BQS, what has been at question in this paper is the effect of BI magnitude on a geological structure.

A Study on the selection of digital filter for an artificial intelligent relay (지능형 보호계전기를 위한 최적 디지탈필터의 선정에 관한 연구)

  • Park, Chul-Won;Kim, Soo-Kyung;Kim, Chul-Whan;Shin, Myong-Chul
    • Proceedings of the KIEE Conference
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    • 1996.07b
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    • pp.664-667
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    • 1996
  • The role of protective relaying system is important in the power system stability and reliability. Conventional relaying schemes have had many problems that adaptiveness for delicate variance of objective power systems is poor, and so on. In these days, in order to overcome the weaknesses, the studies to application of artificial intelligent scheme are required. In this paper, as the preceding research for development of intelligent protective relays, we tried to select the most suitable digital filter using comparison of frequency response and performance of wanted frequency component extraction etc.

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Electrical Characteristics of Organic Light Emitting Diodes (OLED) using the cathode change (다양한 혼합 전극을 사용한 Organic Light Emitting Diodes(OLEDs)의 전기적 특성)

  • Lee, Hyun-Koo;Kim, Jun-Ho;Kim, Young-Kwan
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.475-476
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    • 2005
  • Efficient electron injection is essential to achieve bright and efficient organic light-emitting diodes (OLEDs). In spite of high work function of Al, it is a common cathode because of its stability. In this paper, to overcome the poor electron injection in OLEDs with Al cathode, OLEDs with various composite cathodes were fabricated and investigated using a conventional OLEDs structure of indium tin oxide ITO/NPB(40 nm)/$Alq_3$(50 nm)/Al. composite cathodes were composed of alkaline materials such as Ca and Li, Al deposition or codeposited with AI. We showed best performance at the device with composite cathode (LiF/Al).

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