• Title/Summary/Keyword: Admission Method

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Power Control Based Call Admission Control Method of the CDMA PCS System

  • 이강원;국광호;최정락
    • Korean Management Science Review
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    • v.16 no.1
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    • pp.39-50
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    • 1999
  • This paper proposes a new call admission control method to enhance the reverse link capacity of a cell with heavy traffic in the CDMA PCS system under the uneven traffic load between cells. Since the capacity of a cell in the CDMA system is restricted by the total interference caused by terminals in the own cell and the adjacent cells, we can enhance the capacity of a cell by reducing the interference from other cells if possible. Our power control method allows that the signal powers received in base stations with heavy traffic be larger than those received in base stations with light traffic in order to make the interference due to other cells in the cells with heavy traffic relatively small. In the previous study, it was assumed that the signal power received by each base station in the CDMA PCS system is same when the call admission control algorithm is implemented. We could show that the reverse link capacity of a cell in the CDMA PCS system can be increased about 20% under our call admission control method.

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Performance Analysis of HP Steam Turbines. of LNG Carriers (LNG 운반선용 증기터빈 고압단의 성능해석)

  • Park, Jong-Hwoo;Chung, Kyung-Nam;Kim, Yang-Ik;Cho, Seoung-Hee
    • 유체기계공업학회:학술대회논문집
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    • 2006.08a
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    • pp.275-278
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    • 2006
  • A steam turbine is one of propulsion systems of a LNG carrier, which consists of high pressure (HP) and low pressure (LP) turbines. In order to obtain high power, each one has the form of a multi-stage turbine. Especially, the first stage of a HP turbine is Curtis stage and uses partial admission considering the turbine efficiency. The performance of a HP turbine can be predicted by a mean-line analysis method, because the relatively large value of hub-tip ratio makes the three-dimensional losses small. In this study, a performance analysis method is developed for a multi-stage HP turbine using Chen's loss model developed for the transonic steam turbines. To consider the feature of partial admission, different partial admission models are reviewed, This analysis method can be used in partial load conditions as well as full load condition. The calculation results are also compared with the CFD results about some simple cases to check the accuracy of the program. Performance of two HP turbine models are calculated, and the calculation results are compared with the designed data. The comparison shows the qualitative performance analysis result.

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Maximum Delay-Aware Admission Control for Machine-to-Machine Communications in LTE-Advanced Systems (LTE-Advanced 시스템에서 M2M 통신의 최대 지연시간을 고려한 호 수락 방법)

  • Jun, Kyungkoo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37B no.12
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    • pp.1113-1118
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    • 2012
  • Smart grid and intelligent transportation system draw significant interest since they are considered as one of the green technologies. These systems require a large number of sensors, actuators, and controllers. Also, machine-to-machine (M2M) communications is important because of the automatic control. The LTE-Advanced networks is preparing a set of functions that facilitate the M2M communications, and particularly the development of an efficient call admission control mechanism is critical. A method that groups MTC devices according to QoS constraints and determines the admission depending on the QoS satisfaction is limitedly applied only if the data transmission period and the maximum delay are identical. This paper proposed a call admission control that is free from such limitation and also optimizes the admission process under the certain condition of the transmission period and maximum delay. The theorems regarding the proposed method are presented with the proofs. The simulations confirms its validity and shows it is better in call admission probability than existing works.

Numerical Prediction of Unsteady Flows through Whole Nozzle-Rotor Cascade Channels with Partial Admission

  • Sasao, Yasuhiro;Monma, Kazuhiro;Tanuma, Tadashi;Yamamoto, Satoru
    • International Journal of Fluid Machinery and Systems
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    • v.2 no.3
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    • pp.248-253
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    • 2009
  • This paper presents a numerical study for unsteady flows in a high-pressure steam turbine with a partial admission stage. Compressible Navier-Stokes equations are solved by the high-order high-resolution finite-difference method based on the fourth-order compact MUSCL TVD scheme, Roe's approximate Riemann solver, and the LU-SGS scheme. The SST-model is also solved for evaluating the eddy-viscosity. The unsteady two-dimensional flows through whole nozzle-rotor cascade channels considering a partial admission are numerically investigated. 108 nozzle passages with two blockages and 60 rotor passages are simultaneously calculated. The influence of the flange in the nozzle box to the lift of rotors is predicted. Also the efficiency of the partial admission stage changing the number of blockages and the number of nozzles is parametrically predicted.

Scalable Quasi-Dynamic-Provisioning-Based Admission Control Mechanism in Differentiated Service Networks

  • Rhee, Woo-Seop;Lee, Jun-Hwa;Yu, Jae-Hoon;Kim, Sang-Ha
    • ETRI Journal
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    • v.26 no.1
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    • pp.27-37
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    • 2004
  • The architecture in a differentiated services (DiffServ) network is based on a simple model that applies a per-class service in the core node of the network. However, because the network behavior is simple, the network structure and provisioning is complicated. If a service provider wants dynamic provisioning or a better bandwidth guarantee, the differentiated services network must use a signaling protocol with QoS parameters or an admission control method. Unfortunately, these methods increase the complexity. To overcome the problems with complexity, we investigated scalable dynamic provisioning for admission control in DiffServ networks. We propose a new scalable $qDPM^2$ mechanism based on a centralized bandwidth broker and distributed measurement-based admission control and movable boundary bandwidth management to support heterogeneous QoS requirements in DiffServ networks.

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Aerodynamic Shape Design of a Partial Admission Turbine Using CFD (CFD를 이용한 부분흡입형 터빈 공력형상 설계)

  • Lee, Eun-Seok
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.11 s.254
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    • pp.1131-1138
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    • 2006
  • Aerodynamic shape design of a partial admission turbine using CFD has been performed. Two step approaches are adopted in this study. Firstly, two-dimensional blade shape is optimized using CFD and genetic algorithm. Initially, the turbine cascade shape is represented by four design parameters. By controlling the design parameters as variables, the non-gradient search is analyzed for obtaining the maximum efficiency. The final two-dimensional blade proved to have a more blade power than the initial blade. Secondly, the three-dimensional CFD analysis including the nozzle, rotor and stator has been conducted. To avoid a heavy computational load due to an unsteady calculation, the frozen rotor method is implemented in steady calculation. The frozen rotor method can detect a variation of the flow-field dependent upon the blade's circumferential position relative to the nozzle. It gives a better idea of wake loss mechanism starting from the lip of the nozzle than the mixing plane concept. Finally, the combination of two and three dimensional design method of the partial admission turbine in this study has proven to be a robust tool in development phase.

Abnormal Vibration of Turbine Control Valve due to Resonance (공진에 의한 터빈 Control Valve 이상 진동)

  • Koo, Jae-Raeyang;Kim, Sung-Hwi;Koo, Woo-Sik;Lee, Woo-Kwang;Kim, Yeon-Hwan;Hwang, Jae-Hyeon
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.2100-2104
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    • 2004
  • Amount of Electricity which product generator decide control valve at Turbine. Operating method of Control valve have two mode. First operating method is Partial Arc Admission, and second operating method is Full Arc Admission. Failure of Control Valve have on serious damage electricity lineage. In this Paper, We have investigated resonance that Control Valve spring casing.

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The Effects of an Admission-Education Program on Knowledge, Self-Efficacy, Self-Care and Glucose Control in Type 2 Diabetes Patients (당뇨입원교육프로그램이 제2형 당뇨병 환자의 지식, 자기효능감, 자가관리 및 당 조절에 미치는 효과)

  • Lee, Young-Ran;Kang, Mi-Ae;Kim, Pa-Geon
    • The Journal of Korean Academic Society of Nursing Education
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    • v.14 no.1
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    • pp.12-19
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    • 2008
  • Purpose: This study was performed to explore the effects of an admission-education program on knowledge, self-efficacy, self-care and glucose control in type 2 diabetes patients. Method: A single group pre-post test design was used. Twenty-one patients participated in this program during 6 days which consisted of education and practice about exercise, diet, self-care and prevention of complications. Variables at baseline, 3 months, and 6 months were measured. Results: Knowledge level, self-care level and self-efficacy were significantly increased over time after the admission-education program. The $HbA_1C$ level and glucose level in urine were significantly decreased over time after the admission-education program. Conclusion: The admission-education program can increase levels of knowledge, self-care, self-efficacy and decrease glucose levels. Therefore, this admissioneducation program was shown to have a positive effect on the management of diabetes.

Clinical study on circulating blood and extinguishing blood stasis method in acute ischemic stroke patients (급성(急性) 뇌경색환자(腦硬塞患者)에서 활혈화어(活血化瘀) 치법(治法)의 응용(應用))

  • Kim Dong-Woung
    • Journal of Society of Preventive Korean Medicine
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    • v.3 no.1
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    • pp.147-155
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    • 1999
  • In order to investigate the effect of circulating blood and extinguishing blood stasis method on acute ischemic stroke treatment, we compared muscle weakness in two groups. Dansamhwanotang was administered to experimental group and the Sopungtang was administered to comparison group. In prospective and consecutive study, 24 patients(male 14, female 10) were admitted to hospital within 6hours(median $4.21{\pm}2.45)$ after stroke attack. All of them were diagnosed computed tomography as acute cerebral infarction. We divided that patients into two groups. The experimental group was 13, took median $4.17{\pm}1.72hrs$ to admission after stroke attack and the comparison group 11, median $4.31{\pm}2.72hrs$ to admission after stroke attack. There was no statistical difference in time consumed from stroke onset to admission(P>0.05). Muscle weakness was measured on admission and 7 days later on AMA(American Medical Association) method. In the experimental group, muscle weakness on admission was $2.23{\pm}0.51$ and $2.79{\pm}0.72$ in upper and lower extremity, respectively. In comparison group, muscle weakness on admission was $2.17{\pm}0.43$ and $2.67{\pm}0.82$ in upper and lower extremity, respectively. There was no difference in muscle weakness(P〈0.05). In 7 days after, muscle weakness was $2.31{\pm}0.35$ in upper extremity and $3.15{\pm}0.12$ in lower extremity in experimental group, and $2.27{\pm}0.74$ in upper extremity and $3.45{\pm}0.48$, lower extremity in comparison group. There was no meaningful improvement statistically in upper extremity(p<0.05) but significant evolution in lower extremity(p<0.05). The muscle weakness comparison between admission time and 7 days later was as follows. Experimental group had improvement at the degree of $0.24{\pm}0.92$, $0.42{\pm}0.82$ in upper and lower extremity, respectively and comparison group, $0.12{\pm}0.82$, $0.27{\pm}0.97$ in same part(p<0.05). So, Dansamhwanotang administered group had more good muscle weakness improvement than Sopungtang administered group(P>0.05). From the above result, I suppose that circulating blood and extinguishing blood stasis method helps recover hemiparesis caused by acute ischemic cerabral disease, in acute stage at least.

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Design of the Call Admission Control System of the ATM Networks Using the Fuzzy Neural Networks (퍼지 신경망을 이용한 ATM망의 호 수락 제어 시스템의 설계)

  • Yoo, Jae-Taek;Kim, Choon-Seop;Kim, Yong-Woo;Kim, Young-Han;Lee, Kwang-Hyung
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.8
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    • pp.2070-2079
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    • 1997
  • In this paper, we proposed the FNCAC (fuzzy neural call admission control) scheme of the ATM networks which used the benefits of fuzzy logic controller and the learning abilities of the neural network to solve the call admission control problems. The new call in ATM networks is connected if QoS(quality of service) of the current calls is not affected due to the connection of a new call. The neural network CAC(call admission control) system is predictable system because the neural network is able to learn by the input/output pattern. We applied the fuzzy inference on the learning rate and momentum constant for improving the learning speed of the fuzzy neural network. The excellence of the proposed algorithm was verified using measurement of learning numbers in the traditional neural network method and fuzzy neural network method by simulation. We found that the learning speed of the FNCAC based on the fuzzy learning rules is 5 times faster than that of the CAC method based on the traditional neural network theory.

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