• 제목/요약/키워드: Rate performance

검색결과 16,536건 처리시간 0.046초

Transmission Performance of Half-Symbol-Rate-Carrier Offset QPSK Modulation in Band-limited Channels

  • Yeo, Hyeop-Goo
    • Journal of information and communication convergence engineering
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    • 제7권2호
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    • pp.152-156
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    • 2009
  • This paper examines the BER performance of the recently proposed half-symbol-rate-carrier (HSRC) offset quadrature phase-shift-keying (OQPSK) receiver for high-speed data communication. A modified demodulation technique using a bit-time period signal integration, the bit-error-rate (BER) performance of the HSRC-OQPSK signal improves more than 4dB compared to that of a demodulation technique using a symbol-time period integration. This paper also examines the BER performance of modified demodulation with various band-limited channels modeled using low-pass filters, and the three different data-rate systems are simulated and compared with the performance of the system using the conventional demodulation technique.

평면식 건조기의 적정작업조건 설정에 관한 연구 (Study on The Qptimization of Operating Conditions of batch-type Grain Dryer)

  • 박경규;정창주
    • 한국농공학회지
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    • 제16권4호
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    • pp.3600-3610
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    • 1974
  • Experimental work of batch-type dryer was conducted to develop its optimurm operating conditions by analyzing the major factors which affect the drying performance. A laboratory batch-type dryer was constructed and tested for various levels of heated-air rates, and depths of grain deposit. Tong-il rice variety having the initial moisture content of approximaely 23 per cent in wet basis was used for the experiment. The criteria selected for establishing the optimum operating condition were the drying performance rate, the thermal efficiency, and the operational cost of the dryer. The results of the study are summarized as follows: 1. The performance rate of dryer for a specific operating condition was defined as total amount of material dried per hour when the moisture content of grains in the upperlayer reaches to 16 per cent in wet basis. The optimum operating conditions as viewed in the rate of drying performance could be justified by functional realtionship between the depth of grain deposit and air flow rate. In other words, there was a definite depth of grain deposit for a given air-rate which make the dryer performance maximum. The optimum grain depth for the batch-type dryer with 3.3㎡ loading area and with the attached axial fan was about 35cm. 2. The thermal efficiency for the dryer was evaluated by the ratio of the latent heat required to evaporate the grain moisture to the heat input required to raise the ambient air-temperature to 40 degree centigrade. The optimum operating condition as viewed in term of thermal efficiency analyzed was that grater depth and lower air flow-rate may be desirable. This condition is contracted with the optimum condition as viewed by the dryer performance rate. 3. The annual operating cost of batch-type dryer was analyzed for different annual hour of use and for different operation condition. The optimum condition as viewed in terms of operating cost was almost identical to one as viewed in terms of dryer performance rate. Therefore, the most economical use of batch-type dryer for the same annual operating hours can be obtained when the dryer operated in the condition of maximum dryer performance rate. Increasing the annual operating hour may be desirable to cut down the dryer operation cost, since the annual hour of dryer use is much sensitive to the operating cost than any peractical conditions of dryer operation. 4. The most desirable operational condition as justified by combining all the criteria, dryer performance rate, thermal efficiency and annual operating cost, could be concluded to operate the dryer in the condition of maximum performance rate. The condition in general is identical to the lowest operation cost for a given annual operating hour.

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다이어프램형 밸브의 유량특성과 동적성능에 관한 연구 (A Study on Flow Rate Characteristic and Dynamic Performance on Diaphragm Solenoid Valve)

  • 정찬세;양순용
    • 드라이브 ㆍ 컨트롤
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    • 제10권3호
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    • pp.27-33
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    • 2013
  • Solenoid valve has used in various industrial field extensively. A solenoid valve has different size, shape and method of operation accordantly to industrial field. Many researchers study on kinds of solenoid valve such as flow rate, dynamic, magnetic field, valve shape and operating method. But the flow rate characteristic and dynamic response time performance on the diaphragm valve are not studied. This paper describes the flow rate characteristic and dynamic response time performance on the diaphragm valve. At first, the diaphragm valve is simulated in AMESim simulation tool. AMESim model found that an effect of valve performance depends on parameter. The parameter is the diaphragm orifice area. And the performance test bench confirms the effect in this parameter. Finally, it finds out the flow rate characteristic and dynamic response time performance on the diaphragm valve.

30% 농도의 산소 공급이 기억력, 혈중 산소 농도, 심박률에 미치는 영향 (The Effect of 30% Oxygen on the Memory Performance, Hyperoxia and Heart Rate)

  • 정순철;탁계래;이봉수
    • 산업공학
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    • 제18권2호
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    • pp.178-183
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    • 2005
  • In this study, changes in memory performance, blood oxygen saturation and heart rate according to 30% concentration oxygen supply were observed. Ten healthy male and female college students (male:$25.8{\pm}0.8$ years, female: $24.2{\pm}1.9$ years) participated in the study. The experiment was performed as Rest (1min.), Control task (1min.), Word presentation (1min.), Reaction time task (1min.), Distractor (2min.), and Word recall (1min.) and the physiological signals such as blood oxygen saturation and heart rate were measured throughout the stages. Subjects who received 30% oxygen recalled more words than those who received 21% oxygen, which shows 30% oxygen supply has influenced positively on memory cognitive performance. When 30% concentration oxygen is supplied, the blood oxygen saturation in the task phases was increased and the heart rate decreased when comparing to 21%. It means that 30% oxygen can stimulate brain activation by increasing actual blood oxygen concentration in the process of cognitive performance, and the heart rate decreases because enough oxygen is supplied to process the cognitive performance.

Outcome and Antecedent of Organizational Effectiveness: Moderation Effect of Strategy

  • KIM, Boine
    • 동아시아경상학회지
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    • 제10권2호
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    • pp.1-17
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    • 2022
  • Purpose - This exploratory study analyzes the performance of the business from the HRM point of view. Analyzed the influence of HRM and organization effectiveness on business performance. Also moderating effect of the strategy is analyzed. Research design, data, and methodology - Two outcome variables are measured, non-financial performance and financial performance. Two organizational effectiveness variables are measured, job satisfaction and organizational commitment. And two HRM areas are measured, HRM practice and organizational culture. Finally, two strategies are measured as moderators, market strategy and product/service strategy. This study analyzed employees of 554 from the 7th HCCP. This study used SEM and MCFA. Result - The results of turnover intention, growth rate, and profit rate verified the influence of HRM and organizational effectiveness. Overall results showed a contrary effect of education & training system implement and participation on job satisfaction and organizational commitment. Among organizational culture, innovation and relation positively affect job satisfaction and organizational commitment. However, antecedents influencing turnover intention, growth rate, and profit rate bear no resemblance. And the MCFA result shows that strategy's group differentiation analysis is meaningful in turnover intention not in financial performance. Conclusion - Based on this study result, management suggestions for turnover intention, growth rate, profit rate, and organizational effectiveness are made. Especially, due to the company's strategy.

Cross-layer Design of Rate and Quality Adaptation Schemes for Wireless Video Streaming

  • Lee, Sun-Hun;Chung, Kwang-Sue
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제4권3호
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    • pp.324-340
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    • 2010
  • Video streaming service over wireless networks is a challenging task because of the changes in the wireless channel conditions that can occur due to interference, fading, and station mobility. To provide an efficient wireless video streaming service, the rate adaptation scheme should improve wireless node performance and channel utilization. Moreover, the quality adaptation scheme should be considered at the streaming application. To meet these requirements, we propose a new cross-layer design for video streaming over wireless networks. This design includes the rate and quality adaptation schemes. The rate adaptation scheme selects the optimal transmission mode and resolves the performance anomaly problem. Based on performance improvement by the proposed rate adaptation scheme, our quality adaptation scheme improves the quality of video streaming. Through performance evaluations, we prove that our cross-layer design improves the wireless channel utilization and the quality of video streaming.

분산 시스템의 결함시 재분배 알고리즘의 선정기준을 위한 특성 분석 (Analysis of Criteria for Selecting Load Redistribution Algorithm for Fault-Tolerant Distributed System)

  • 최병갑
    • 한국시뮬레이션학회논문지
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    • 제3권1호
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    • pp.89-98
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    • 1994
  • In this paper, a criteria for selecting an appropriate load redistribution algorithm is devised so that a fault-tolerance distributed system can operte at its optimal efficience. To present the guideline for selecting redistributing algorithms, simulation models of fault-tolerant system including redistribution algorithms are developed using SLAM II. The job arrival rate, service rate, failure and repair rate of nodes, and communication delay time due to load migration are used as parameters of simulation. The result of simulation shows that the job arrival rate and the failure rate of nodes are not deciding factors in affecting the relative efficiency of algorithms. Algorithm B shows relatively a consistent performance under various environments, although its performance is between those of other algorithms. If the communication delay time is longer than average job processing time, the performance of algorithm B is better than others. If the repair rate is relatively small or communication delay time is longer than service time, algorithm A leads to good performance. But in opposite environments, algorithm C is superior to other algorithms.

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HMO(Health Maintenance Orgarnization)의 내부조직구조와 의료비용절감과의 관계 (The Relationship between HMO's Organizational Structures and Cost Reduction)

  • 김정화
    • 보건행정학회지
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    • 제3권1호
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    • pp.102-123
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    • 1993
  • This study investigates effcts of HMO internal structural arrangements on performance, specially cost reduction measured by hospitalization rate. This study formulates formalization, centralization measured by decision-making participation, differentiation, and coordination as structural factors, considering coordination as an intermediate factor between the rest of structural factors and hospitalization rate. The commonly used HMO types is assumed not effective in explaining performance differences. For the empirical test, I use bootstrap regression analyses with 48 HMOs. The results of the analyses show that HMO types fail to explain differences in hospitalization rate. However, dicision-making participation and differention effectively reduce hospiatalization rate, while frmalization increases hospitalization rate and coordination has nonessential effect on hospitalization rate. And, formalization and decision-making participation positively contribute to achieve coordination in HMO. These findings suggest that the theoretical framework derived from rational-citingency theory of formal organization better explains performance differences of HMOs than HMO types.

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30% 산소 공급에 의한 언어 인지 능력, 혈중 산소 농도, 심박동율의 변화 (Changes in Verbal Cognitive Performance, Blood Oxygen Saturation and Heart Rate due to 30% Oxygen Administration)

  • 정순철;손진훈;탁계래;이정한
    • 한국정밀공학회지
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    • 제22권4호
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    • pp.173-180
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    • 2005
  • In this study, changes in verbal cognitive performance, blood oxygen saturation and heart rate due to 30% concentration oxygen supply were observed. Five male (24.6±0.9) and five female (22.2±1.9) college students were asked to perform 28 verbal cognitive tasks of the same difficulty during two types of oxygen (concentration 21%, 30%) administration. The experimental sequence consisted of Rest1 (1 min.), Control (1 min.), Task (4 min.), and Rest2 (4 min.) and the physiological signals such as blood oxygen saturation and heart rate were measured throughout the stages. The experimental result showed that the performance increased significantly at 30%'s concentration of oxygen rather than 21%'s, which shows oxygen supply has positive influence on verbal cognitive performance. When 30% concentration oxygen is supplied, the oxygen saturation in the blood significantly increased comparing to 21%. The heart rate showed no significant difference. Significant correlations were found between changes in oxygen saturation and cognitive performance. It is suggested that 30% oxygen can stimulate brain activation by increasing actual blood oxygen concentration in the process of cognitive performance.

Roles of Capital Adequacy and Liquidity to Improve Banking Performance

  • MARGONO, Hery;WARDANI, Mursida Kusuma;SAFITRI, Julia
    • The Journal of Asian Finance, Economics and Business
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    • 제7권11호
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    • pp.75-81
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    • 2020
  • This study aims to empirically test the effect of liquidity and adequacy on bank performance through interest rate risk and credit risk. Capital adequacy and liquidity are variables that can affect the ups and downs of opinion, where the bank's performance in this study is the dependent variable. Good credit distribution can minimize the occurrence of defaults. This study uses banking companies in Indonesia that are listed on the Indonesian stock exchange, with a total number of 43 banking companies, this study however, uses only 30 companies ranging from years 2014 to 2019, primarily due to the availability of the limited data. The data analysis techniques used in this study is PLS-SEM with the WarpPLS application. The research results show that capital adequacy and liquidity has a positive effect on bank performance, interest rate risk and credit risk can mediate capital adequacy on bank performance, interest rate risk can mediate liquidity on bank performance, and interest rate risk has a positive effect on bank performance. However, credit risk can't mediate liquidity on bank performance and credit risk does not have a positive effect on bank performance. This is in line with the commercial loan theory, shiftability theory and the doctrine of anticipated income, which explains how best to give credit, both in longer and the shorter term.