• Title/Summary/Keyword: Design stabilization

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Strength and Deformation Characteristics on Stabilized Pavement Geomaterials (II) : Numerical Analysis (안정처리된 도로하부 지반재료의 강도 및 변형특성 (II) : 수치해석)

  • Park, Seong-Wan;Ji, Jong-Keun
    • International Journal of Highway Engineering
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    • v.11 no.2
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    • pp.205-216
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    • 2009
  • As a subsequent study, this paper presents a comparative evaluation of structural responses in asphalt pavements with stabilized foundations. The approach based on a finite element analysis which incorporates non-linear behaviors of pavement geomaterials is used to estimate each performance indicator under standard single axle loading condition. In addition, results from laboratory tests are used to provide physical and mechanical properties of stabilized geomaterials for analyzing various pavement structures. Changes in pavement responses with varying layer thickness and stabilizer contents were investigated. It is found that the effect of layer thickness and stabilizer content is a critical factor in structural response of stabilized pavements. Moreover, a design criterion is proposed for selecting minimum contents of stabilizer of coarse-grained geomaterials based on a result of unconfined compressive strength and proper layer thickness of foundations.

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Special quality research by pulse transformer stabilization by high tension output module of medical ultra series laser II (산부인과용 $CO_2$ 연속형 레이저의 고압출력 모듈에 따른 펄스트랜스 안정화 특성연구(II))

  • Kim, Whi-Young
    • Journal of the Korea Computer Industry Society
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    • v.8 no.1
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    • pp.49-56
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    • 2007
  • Various kind of laser had been used on addition to endoscope for obstetrics and gynecology, gas laser such as CO2 laser had been used mainly much in laparoscope surgical operation mainly Thermal effect of beam displays other result different component parts of cellular tissue and different close of a marketplace of laser beam and priority solidification of temperature increase consists in cellular tissue, and cutting or carbonization process happens and evaporation by breakdown of cellular tissue happens more than $300^{\circ}$. <중략> Ostabilization of pulse transformer by high tension output module of CO2analog laser for obstetrics and gynecology that accomplish marks of honor kind switching and accuracy is required, and stabilize with laser output applying Turn-off in existent hard switching forward converter, on city happened switching damage, damage increase of output diode station recovery special quality, parasitism shock, design and result that manufacture, brought result that improve than existing product. Will be bought to get into superior result if supplement as systematic late.

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On discrete nonlinear self-tuning control

  • Mohler, R.-R.;Rajkumar, V.;Zakrzewski, R.-R.
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10b
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    • pp.1659-1663
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    • 1991
  • A new control design methodology is presented here which is based on a nonlinear time-series reference model. It is indicated by highly nonlinear simulations that such designs successfully stabilize troublesome aircraft maneuvers undergoing large changes in angle of attack as well as large electric power transients due to line faults. In both applications, the nonlinear controller was significantly better than the corresponding linear adaptive controller. For the electric power network, a flexible a.c. transmission system (FACTS) with series capacitor power feedback control is studied. A bilinear auto-regressive moving average (BARMA) reference model is identified from system data and the feedback control manipulated according to a desired reference state. The control is optimized according to a predictive one-step quadratic performance index (J). A similar algorithm is derived for control of rapid changes in aircraft angle of attack over a normally unstable flight regime. In the latter case, however, a generalization of a bilinear time-series model reference includes quadratic and cubic terms in angle of attack. These applications are typical of the numerous plants for which nonlinear adaptive control has the potential to provide significant performance improvements. For aircraft control, significant maneuverability gains can provide safer transportation under large windshear disturbances as well as tactical advantages. For FACTS, there is the potential for significant increase in admissible electric power transmission over available transmission lines along with energy conservation. Electric power systems are inherently nonlinear for significant transient variations from synchronism such as may result for large fault disturbances. In such cases, traditional linear controllers may not stabilize the swing (in rotor angle) without inefficient energy wasting strategies to shed loads, etc. Fortunately, the advent of power electronics (e.g., high-speed thyristors) admits the possibility of adaptive control by means of FACTS. Line admittance manipulation seems to be an effective means to achieve stabilization and high efficiency for such FACTS. This results in parametric (or multiplicative) control of a highly nonlinear plant.

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Preliminary Surgical Result of Cervical Spine Reconstruction with a Dynamic Plate and Titanium Mesh Cage

  • Chung, Dae-Yeong;Cho, Dae-Chul;Lee, Sun-Ho;Sung, Joo-Kyung
    • Journal of Korean Neurosurgical Society
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    • v.41 no.2
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    • pp.111-117
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    • 2007
  • Objective : The objective of this study was to validate the effects of a titanium mesh cage and dynamic plating in anterior cervical stabilization after corpectomy. Methods : A retrospective study was performed on 31 consecutive patients, who underwent anterior cervical reconstruction with a titanium mesh cage and dynamic plating, from March 2004 to February 2006. Twenty-four patients had 1-level and 7 had 2-level corpectomies. Ten patients underwent surgery with a cage of 10-mm diameter and 21 with 13-mm diameter. Neurological status and outcomes were assessed according to Odom's criteria. Sagittal angle, coronal angle, settling ratio, sagittal displacement, and cervical lordosis were used to evaluate the radiological outcomes. Results : In overall, 26 [83.9%] of 31 showed excellent or good outcomes. Thirteen percent [4 cases] of the patients developed surgical complications, such as hoarseness, transient dysphagia, or nerve root palsy. Seven [22.6%] patients had reconstruction failure:5 [20.8%] in the 1-level corpectomy group and 2 [28.5%] in the 2-level corpectomy group. Revisions were required in 2 patients with plate pullout due to significant instability. However, none of 5 patients who demonstrated cage displacement or screw pullout, underwent a revision. Radiographs revealed bony consolidation in 96.3% of the patients, including 6 patients with implantation failure during the follow-up period. Conclusion : Based on our preliminary results, the titanium mesh cage and dynamic plating was effective for cervical reconstruction after corpectomy. The anterior cervical reconstruction performed with dynamic plates is considered to reduce stress shielding and greater graft compression that is afforded by the unique plate design.

Case Study on Global Slope Failure Case of Segmental Retaining Wall (블록식보강토옹벽의 전면 사면붕괴 사례연구)

  • Han, Jung-Geun;Cho, Sam-Deok;Jeong, Sang-Seom;Lee, Kwang-Wo;Hong, Ki-Kwon
    • Journal of the Korean Geosynthetics Society
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    • v.4 no.2
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    • pp.47-56
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    • 2005
  • Recently, geosynthetic reinforced earth walls are gradually replacing conventional concrete retaining walls for reasons of economy, expediency of construction, and aesthetics. A number of reinforced soil walls having more than 10m heights have been constructed to make more effective development in the country. However, mistakes in design and construction of reinforced earth walls have resulted in many troubles such as failure of reinforced earth walls, horizontal deformationor breakdown of facings, and so forth during or after construction. In this paper, a case study on global sliding failure of a geogrid-reinforced tiered wall is carried out to investigate the causes of the failure and suggest the proper countermeasures. From the subsurface investigation and field instrumentation, It is found that the cause of the global sliding failure was occurred by decreasing of bearing capacity of foundation ground induced by infiltration of rainwater.

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Stabilizing Inverted Pendulum System Using Fuzzy Controller Based on State Variables Combination (상태변수 조합 퍼지 제어기를 이용한 도립진자 시스템의 안정화)

  • Lee, Yun-Hyung;Kim, Jong-Phil;Jin, Gang-Gyoo;So, Myung-Ok
    • Journal of Advanced Marine Engineering and Technology
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    • v.36 no.8
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    • pp.1104-1110
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    • 2012
  • The inverted pendulum system is a common, interesting control problem that involves many basic elements of control theory. In the early, controls of stabilization for the inverted pendulum system were used classical methods like PD, PID controller. In recently, however, control methods based on modern and intelligent control theory are widely applied. The fuzzy logic controller which is often used in nonlinear control is a little too hard to design due to increasing fuzzy rules rapidly if the given system like inverted pendulum has many state variables. Also, in case the state variables are divided into two parts, two fuzzy controllers are needed in the control system. In this paper, the authors propose FCSC(Fuzzy Controller based on State variables Combination) that reorganized into two new signals depending on the physical meaning of the four state variables of the inverted pendulum system. The proposed method is applied to the inverted pendulum system and simulations are accomplished to illustrate the control performance.

A Study on the SVC System Stabilization Using a Neural Network (신경회로망을 이용한 SVC 계통의 안정화에 관한 연구)

  • 정형환;허동렬;김상효
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.14 no.3
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    • pp.49-58
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    • 2000
  • This paper deals with a systematic approach to neural network controller design for static VAR compensator (SVC) using a learning algorithm of error back propagation that accepts error and change of error as inputs, the momentum learning technique is used for reduction of learning time, to improve system stability. A SVC, one of the Flexible AC Transmission System(FACTS), constructed by a fixed capacitor(FC) and a thyristor controlled reactor(TCR), is designed and implemented to improve the damping of a synchronous generator, as well as controlling the system voltage.TO verify the robustness of the proposed method, we considered the dynamic response of generator rotor angle deviation, angular velocity deviation and generator terminal voltage by applying a power fluctuation and rotor angle fluctuation in initial point when heavy load and normal load. Thus, we prove the usefulness of proposed method to improve the stability of single machine-infinite bus with SVC system.

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Molecular Characterization of Chicken Toll-like Receptor 7

  • Chai, Han-Ha;Suk, Jae Eun;Lim, Dajeong;Lee, Kyung-Tai;Choe, Changyong;Cho, Yong-Min
    • Reproductive and Developmental Biology
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    • v.39 no.4
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    • pp.105-115
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    • 2015
  • Toll-like receptor 7 (TLR7) is critical for the triggering of innate immune response by recognizing the conserved molecular patterns of single-stranded RNA (ssRNA) viruses and mediated antigenic adaptive immunity. To understand how TLR7 distinguish pathogen-derived molecular patterns from the host self, it is essential to be able to identify TLR7 receptor interaction interfaces, such as active sites or R848-agonist binding sites. The functional interfaces of TLR7 can serve as targets for structure-based drug design in studying the TLR7 receptor's structure-function relationship. In contrast to mammalian TLR7, chicken TLR7 (chTLR7) is unknown for its important biological function. Therefore, it has been targeted to mediate contrasting evolutionary patterns of positive selection into non-synonymous SNPs across eleven species using TLR7 conservation patterns (evolutionary conserved and class-specific trace residues), where protein sequence differences to the TLR7 receptors of interest record mutation that have passed positive section across the species. In this study, we characterized the Lys609 residue on chTLR7-ECD homodimer interfaces to reflect the current tendency of evolving positive selection to be transfer into a stabilization direction of the R848-agonist/chTLR7-ECDs complex under the phylogenetically variable position across species and we suggest a potential indicator for contrasting evolutionary patterns of both the species TLR-ECDs.

Stabilization Controller Design of a Container Crane for High Productivity in Cargo Handling Using a RCGA (실수코딩유전알고리즘을 이용한 하역생산성 향상용 컨테이너 크레인의 안정화 제어기 설계)

  • Lee, Soo-Young;Ahn, Jong-Kap;Choi, Jae-Jun;Son, Jeong-Ki;Lee, Yun-Hyung;So, Myung-Ok
    • Journal of Navigation and Port Research
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    • v.31 no.6
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    • pp.515-521
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    • 2007
  • To increase the stevedore efficiency and service level at container terminal, it is essential to reduce working time of container crane which has a bottle neck in the logistic flow of container. The working speed and safety are required to be improved by controlling the movement of the trolley as quick as possible without big overshoot and any residual swing motion of container in the vicinity of target position. This paper presents optimal state feedback control using RCGAs in the case of existing constrained conditions

An Integrative Care Model of Clinical Pathway Approach for Acute Pain after Back Surgery: A Protocol for Clinical Trial (요추 수술 후 급성기 통증 환자에 대한 통합의학 표준임상경로 임상시험 프로토콜)

  • Kim, Byung-Jun;Shin, Byung-Cheul;Hwang, Man-suk;Shin, Kyung-Min;Heo, In;Lim, Kyeong-Tae;Park, In-Hwa;Son, Dong-Wuk;Hwang, Eui-Hyoung
    • Journal of Korean Medicine Rehabilitation
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    • v.27 no.4
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    • pp.111-119
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    • 2017
  • Objectives Clinical pathway (CP), is management plans that display goals for patients and have led to improve outcomes for many diseases. In Korea, Interest in Korean medicine's stabilization (Clinical pathway, Clinical Practice Guideline) is increasing, But the number of studies is scare. Method and Analysis This trials composes nonequivalent control group pretest-posttest design to conduct clincal pathway trial for the acute pain after back surgery. The subjects were 10 control patients with back surgery, and 10 experimental patients with application of integrative CP. Each group patient will observed 6 weeks. We check validation of CP. Also we compared the patient's status using the pain, function, Quality of life index between the two groups. Discussion This trial is the first CP for the acute pain after back surgery using integrative medicine concepts. Aim of this trial is to find the effectiveness and validity of clincal pathway for acute pain after back surgery.