• Title/Summary/Keyword: FM band

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Assessing the Benefits of Incorporating Rainfall Forecasts into Monthly Flow Forecast System of Tampa Bay Water, Florida (하천 유량 예측 시스템 개선을 위한 강우 예측 자료의 적용성 평가: 플로리다 템파 지역 사례를 중심으로)

  • Hwang, Sye-Woon;Martinez, Chris;Asefa, Tirusew
    • Journal of The Korean Society of Agricultural Engineers
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    • v.54 no.4
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    • pp.127-135
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    • 2012
  • This paper introduced the flow forecast modeling system that a water management agency in west central Florida, Tampa Bay Water has been operated to forecast monthly rainfall and streamflow in the Tampa Bay region, Florida. We evaluated current 1-year monthly rainfall forecasts and flow forecasts and actual observations to investigate the benefits of incorporating rainfall forecasts into monthly flow forecast. Results for rainfall forecasts showed that the observed annual cycle of monthly rainfall was accurately reproduced by the $50^{th}$ percentile of forecasts. While observed monthly rainfall was within the $25^{th}$ and $75^{th}$ percentile of forecasts for most months, several outliers were found during the dry months especially in the dry year of 2007. The flow forecast results for the three streamflow stations (HRD, MB, and BS) indicated that while the 90 % confidence interval mostly covers the observed monthly streamflow, the $50^{th}$ percentile forecast generally overestimated observed streamflow. Especially for HRD station, observed streamflow was reproduced within $5^{th}$ and $25^{th}$ percentile of forecasts while monthly rainfall observations closely followed the $50^{th}$ percentile of rainfall forecasts. This was due to the historical variability at the station was significantly high and it resulted in a wide range of forecasts. Additionally, it was found that the forecasts for each station tend to converge after several months as the influence of the initial condition diminished. The forecast period to converge to simulation bounds was estimated by comparing the forecast results for 2006 and 2007. We found that initial conditions have influence on forecasts during the first 4-6 months, indicating that FMS forecasts should be updated at least every 4-6 months. That is, knowledge of initial condition (i.e., monthly flow observation in the last-recent month) provided no foreknowledge of the flows after 4-6 months of simulation. Based on the experimental flow forecasts using the observed rainfall data, we found that the 90 % confidence interval band for flow predictions was significantly reduced for all stations. This result evidently shows that accurate short-term rainfall forecasts could reduce the range of streamflow forecasts and improve forecast skill compared to employing the stochastic rainfall forecasts. We expect that the framework employed in this study using available observations could be used to investigate the applicability of existing hydrological and water management modeling system for use of stateof-the-art climate forecasts.

The Change of Functional Fitness and Bone Mineral Density on a Long-Term Combined Exercise Intervention in Breast Cancer Survivors. (유방암 생존자의 장기간 복합 운동중재에 따른 기능적 체력과 골밀도의 변화)

  • Kim, Yang-Sook;Kim, Mi-Sook
    • Journal of Life Science
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    • v.18 no.7
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    • pp.968-973
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    • 2008
  • The study was to provide basic data and to examine the effect of combined exercise for 12 months on functional fitness and bone mineral density (BMD) in breast cancer survivors. The subjects of this study were 40 to 60-year-old married women (N=24) who finished their treatments chemotherapy and radiation therapy. They were divided into two groups that exercise group and exercise with alendronate group. Eighteen (T-score=$-2.2{\pm}0.8$) of the 24 women who were diagnosed osteopenia (N=15) and osteoporosis (N=3), participated in combined exercise (EG). The other six (T-score=$-4.6{\pm}0.9$) women who were diagnosed as osteoporosis (EDG), participated in the combined exercise program with osteoporosis drug (Alendronate 70 mg/w). The result of the analysis was as follows: Twelve months after, the participants (N=24) had a significant increase of the items such as sit and reach ups, grip strength (R and L) and sit ups test of functional fitness in the periods. In body composition, FM (fat mass) had significant decrease in periods. In the comparison of BMD, EG (N=18) had no change, while EDG (N=6) had significant improvement in L1, T12 and T-score after 12months. Consequently, complex exercise program (Hatha yoga, elastic band, gym ball) had positive effect on functional fitness and bone mineral density. We suggest that complex exercise program can be applied as recovery program after breast cancer surgery. Further research needs various and repetitive studies from more different targets or methods in the exercise program for its improvement.

Seabed Classification Using the K-L (Karhunen-Lo$\grave{e}$ve) Transform of Chirp Acoustic Profiling Data: An Effective Approach to Geoacoustic Modeling (광역주파수 음향반사자료의 K-L 변환을 이용한 해저면 분류: 지질음향 모델링을 위한 유용한 방법)

  • Chang, Jae-Kyeong;Kim, Han-Joon;Jou, Hyeong-Tae;Suk, Bong-Chool;Park, Gun-Tae;Yoo, Hai-Soo;Yang, Sung-Jin
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.3 no.3
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    • pp.158-164
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    • 1998
  • We introduce a statistical scheme to classify seabed from acoustic profiling data acquired using Chirp sonar system. The classification is based on grouping of signal traces by similarity index, which is computed using the K-L (Karhunen-Lo$\grave{e}$ve) transform of the Chirp profiling data. The similarity index represents the degree of coherence of bottom-reflected signals in consecutive traces, hence indicating the acoustic roughness of the seabed. The results of this study show that similarity index is a function of homogeneity, grain size of sediments and bottom hardness. The similarity index ranges from 0 to 1 for various types of seabed material. It increases in accordance with the homogeneity and softness of bottom sediments, whereas it is inversely proportional to the grain size of sediments. As a real data example, we classified the seabed off Cheju Island, Korea based on the similarity index and compared the result with side-scan sonar data and sediment samples. The comparison shows that the classification of seabed by the similarity index is in good agreement with the real sedimentary facies and can delineate acoustic response of the seabed in more detail. Therefore, this study presents an effective method for geoacoustic modeling to classify the seafloor directly from acoustic data.

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Design of Digitalized SECAM Video Encoder with Modified Anti-cloche filter and SECAM Video Decoder with BPF and Error-free Square Root (개선된 Anti-cloche Filter와 BPF 그리고 오차가 없는 제곱근기를 사용한 SECAM Encoder와 Decoder의 설계)

  • Ha, Joo-Young;Kim, Joo-Hyun;Kang, Bong-Soon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.3
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    • pp.511-516
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    • 2006
  • In this raper, we propose the Sequentiel Couleur Avec Memoire or Sequential Color with Memory (SECAM) video encoder system using modified anti-cloche filters and the SECAM video decoder system using a band pass filter (BPF) and an error-free square root. The SECAM encoder requires an anti-cloche filter recommended by International Telecommunication Union-Recommendation (ITU-R) Broadcasting service Television (BT) 470. However, the design of the anti-cloche filter is difficult because the frequency response of the anti-cloche filter is very sharp around rejection-frequency area. So, we convert the filter into a hish pass filter (HPF) by shifting the rejection frequency of 4.286MHz to 0Hz frequency. The design of HPF becomes very easy, compared to that of the anti-cloche filter. The proposed decoder also uses an error-free square root, two differentiators and trigonometric functions to extract color-component information of Db and Dr accurately from frequency modulation (FM) signals in SECAM systems. Also, the BPF in decoder it used for removing color noise in chrominance and dividing CVBS into chrominance and luminance. The proposed systems are experimentally demonstrated with Altera FPGA APEX20KE EP20K1000EBC652-3 device and TV sets.

PRODUCT10N OF KSR-III AIRGLOW PHOTOMETERS TO MEASURE MUV AIRGLOWS OF THE UPPER ATMOSPHERE ABOVE THE KOREAN PENINSULAR (한반도 상공의 고층대기 중간 자외선 대기광 측정을 위한 KSR-III 대기광도계 제작)

  • Oh, T.H.;Park, K.C.;Kim, Y.H.;Yi, Y.;Kim, J.
    • Journal of Astronomy and Space Sciences
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    • v.19 no.4
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    • pp.305-318
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    • 2002
  • We have constructed two flight models of airglow photometer system (AGP) to be onboard Korea Sounding Rocket-III (KSR-III) for detection of MUV dayglow above the Korean peninsular. The AGP system is designed to detect dayglow emissions of OI 2972${\AA}$, $N_2$ VK(0,6) 2780${\AA}$, $N_2$ 2PG 3150${\AA}$ and background 3070${\AA}$ toward the horizon at altitudes between 100 km and 300 km. The AGP system consists of a photometer body, a baffle an electronic control unit and a battery unit. The MUV dayglow emissions enter through a narrow band interference filter and focusing lens of the photometer, which contains an ultraviolet sensitive photomultiplier tube. The photometer is equipped with an in-flight calibration light source on a circular plane that will rotate at the rocket's apogee. A bane tube is installed at the entry of the photometer in order to block strong scattering lights from the lower atmosphere. We have carried out laboratory measurements of sensitivity and in-flight calibration light source for the AGP flight models. Although absolute sensitivities of the AGP flight models could not be determined in the country, relative sensitivities among channels are well measured so that observation data during rocket flight in the future can be analyzed with confidence.