• Title/Summary/Keyword: improvement method

Search Result 14,261, Processing Time 0.039 seconds

Capacity Improvement of BS-CDMA System by Spectrum Overlapping Method between Adjacent Channels

  • Kim, Yun-Young;Lee, Dong-Hun;An, Byeong-Rok;Chung, Ki-Ho;Ryu, Heung-Gyoon
    • Journal of electromagnetic engineering and science
    • /
    • v.1 no.2
    • /
    • pp.120-125
    • /
    • 2001
  • The capacity improvement in the DS-CDMA system can be obtained by allowing spectrum-overlap between adjacent channels. In this paper, an analysis for capacity improvement is newly considered according to the various chip waveforms in the partial spectrum-overlapped DS-CDMA system. Optimum-overlapping ratio is numerically found to obtain maximum capacity improvement for each chip waveform. Assuming the bandwidth containing 95% of the total power, i.e., 95% power bandwidth, rectangular chip waveform has the largest capacity improvement in the considered chip waveforms and then the amount of improvement is 136.5% at overlapping ratio 1.5 for BER = $10^{-3}$TEX> . Furthermore, as the required BER becomes lower, the capacity improvement gets smaller for a1l of chip waveforms. For the unequal power channels, it is shown that the larger capacity improvement is achieved as the power of desired channel becomes larger than that of adjacent channels. And the capacity improvement can be obtained even though the desired channel power is lower than the adjacent channel power.

  • PDF

Design and Fabrication of Predistorter for PCS Using Feedforward Method (Feedforward 방식을 이용한 PCS용 Predistorter의 설계 및 제작)

  • 최현주;박명석;박천석
    • Proceedings of the IEEK Conference
    • /
    • 2000.11a
    • /
    • pp.349-352
    • /
    • 2000
  • In this paper, predistorter for PCS has been designed and fabricated. In predistorter system IMD signal generator was very important element. In this LPA IMD signal generator was fabricated using main signal cancellation and error signal cancellation of feedforward method and two amplifier that had same IMD characteristics. This LPA showed IMD characteristics of 52㏈c operation in 48㏈m(60W) and made 12㏈ IMD characteristic improvement when it was excited by two tone. In this LPA, to make more IMD characteristic improvement the IMD characteristic resemblance between main amplifier and predistortion amplifier is very important.

  • PDF

Case Study on Technology and Regulation Improvement of Subway Maintenance Monitoring (지하철 유지관리 계측의 기술 및 제도 개선방안 연구)

  • 우종태;김홍석
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2000.03b
    • /
    • pp.303-308
    • /
    • 2000
  • By means of analyzing of monitoring technology and monitoring regulation based on maintenance monitoring system installed in subway tunnel section, it needs monitoring system, development of operating program, monitoring analyzing system and development of analysis method, establishment of maintenance monitoring standard specification, and performance of responsible monitoring supervision for applying to subway monitoring maintenance effectively in future. It requires specialized monitoring and legislation of monitoring subcontract, improvement of monitoring work contract method, establishment the standard payment of monitoring, and effective calibration and correction of monitoring system in the plan of improving monitoring regulation.

  • PDF

Arthroscopic Treatment of Coronoid Impingement in Stiff Elbow

  • Lee Yong Geol
    • The Academic Congress of Korean Shoulder and Elbow Society
    • /
    • 1999.03a
    • /
    • pp.38-40
    • /
    • 1999
  • $\cdot$ Arthroscopic management is the effective method with acceptable results for coronoid impingement of stiff elbow contributing to the functional improvement and pain relief. $\cdot$ The functional improvement and pain relief seem to be affected by the severity of a degenerative change of the elbow joint. $\cdot$ Excision of coronoid process is required in a marked limitation of further flexion in addition to deeping of the coronoid fossa and anterior capsular release. $\cdot$ Excision of olecranon tip or posterior capsular release are effective method in severe flexion contracture.

  • PDF

Review of measurement of impact sound improvement for light-weight floor (경량 바닥구조의 바닥충격음 저감량 실험실 측정방법 고찰)

  • Jang, Gil-Soo;Jung, Kwang-Yong;Kim, Sun-Woo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2002.11b
    • /
    • pp.950-955
    • /
    • 2002
  • ISO 140-11 specifies a method for measuring the acoustic properties of floor coverings from the view-point of reducing impact sound transmission. This test method is limited to the specification of procedures for the physical measurement of sound originating from an artificial impact source under laboratory conditions. In this study, ISO 140-11 was reviewed to applicable to domestic floor coverings installed on lightweight floors.

  • PDF

Image Enhancement Method by Saturation and Contrast Improvement

  • Park, Gyu-Hee;Cho, Hwa-Hyun;Yun, Jong-Ho;Choi, Myung-Ryul
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2007.08b
    • /
    • pp.1139-1142
    • /
    • 2007
  • In this paper, an image enhancement method by saturation and contrast improvement is proposed. Histogram equalization with color difference makes higher contrast. By generating saturation amplification ratio with color difference, the saturation improves effectively. The experimental results show that the proposed algorithm has higher contrast and more natural - look than the conventional methods.

  • PDF

Suggestion for method to improve power consumption of the ZigBee RF4CE platform

  • Woo, Eun-Ju;Moon, Yu-Sung;Kim, Jung-Won
    • Journal of IKEEE
    • /
    • v.22 no.2
    • /
    • pp.476-479
    • /
    • 2018
  • This paper proposes a method for reducing the amount of current consumption by the transceiver based remote control and the ZigBee RF4CE network layer step. We have studied how to improve power efficiency at short transition time through duty rate management. Also, comparing the measured current consumption before and after the improvement, we confirmed the correlation between the data transmission speed improvement and the current reduction.

A Study on the Improvement of Sculptured surface Sopography in Milling Operation by Using Tertiary Motion Attachment (밀링작업에서 보조장치를 이용한 자유곡면의 표면거칠기 향상에 관한 연구)

  • 홍민성
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.5 no.3
    • /
    • pp.66-72
    • /
    • 1996
  • The applicability of a new method, termed the whirling motion concept, for the improvement of the surface finish in milling three-dimensional sculptured surfaces has been investigated. A method for implementing this concept o conventional NC machines that utilize a suitably configured attachment has been proposed. The tool path equation for the ball-end milling process, based on the surface-shaping system, has been obtained. Both results of the computer simulation and the experiment verified the proposed approach.

  • PDF

Review of measurement of impact sound improvement for light-weight floor (경량바닥구조의 바닥충격음 저감량 실험실 측정방법 고찰)

  • Jang, Gil-Soo;Kim, Sun-Woo;Jung, Kwang-Yong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2002.11a
    • /
    • pp.392.2-392
    • /
    • 2002
  • ISO 140-11 specifies a method for measuring the acoustic properties of floor coverings from the view-point of reducing impact sound transmission. This test method is limited to the specification of procedures for the Physical measurement of sound originating from an artificial impact source under laboratory conditions. In this study, ISO 140-11 was reviewed to applicable to domestic floor coverings installed on lightweight floors.

  • PDF

Project Risk Management & Observational Method for soft ground improvement (연약지반을 대상으로 한 프로젝트 리스크와 현장계측의 과제와 대책)

  • Imanishi, Hajime
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2006.10a
    • /
    • pp.509-514
    • /
    • 2006
  • Considering the risk management, there are many examples and various studies for the corporation risk. However, I have never seen the project risk management that applied a construction site for practical approach. Therefore, I have developed a chart (I-Chart) for the project risk management, and also built a model (I-Chart scenario analysis) that I could use. I applied this model to container yard reclaimed land in harbor construction with approaching of geotechnical engineering.

  • PDF