• Title/Summary/Keyword: weighted average method

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Rainfall Variations of Temporal Characteristics of Korea Using Rainfall Indicators (강수지표를 이용한 우리나라 강수량의 시간적인 특성 변화)

  • Hong, Seong-Hyun;Kim, Young-Gyu;Lee, Won-Hyun;Chung, Eun-Sung
    • Journal of Korea Water Resources Association
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    • v.45 no.4
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    • pp.393-407
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    • 2012
  • This study suggests the results of temporal and spatial variations for rainfall data in the Korean Peninsula. We got the index of the rainfall amount, frequency and extreme indices from 65 weather stations. The results could be easily understood by drawing the graph, and the Mann-Kendall trend analysis was also used to determine the tendency (up & downward/no trend) of rainfall and temperature where the trend could not be clear. Moreover, by using the FARD, frequency probability rainfalls could be calculated for 100 and 200 years and then compared each other value through the moment method, maximum likelihood method and probability weighted moments. The Average Rainfall Index (ARI) which is meant comprehensive rainfalls risk for the flood could be obtained from calculating an arithmetic mean of the RI for Amount (RIA), RI for Extreme (RIE), and RI for Frequency (RIF) and as well as the characteristics of rainfalls have been mainly classified into Amount, Extremes, and Frequency. As a result, these each Average Rainfall Indices could be increased respectively into 22.3%, 26.2%, and 5.1% for a recent decade. Since this study showed the recent climate change trend in detail, it will be useful data for the research of climate change adaptation.

An Adaptive Proximity Route Selection Method in DHT-Based Peer-to-Peer Systems (DHT 기반 피어-투-피어 시스템을 위한 적응적 근접경로 선택기법)

  • Song Ji-Young;Han Sae-Young;Park Sung-Yong
    • The KIPS Transactions:PartA
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    • v.13A no.1 s.98
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    • pp.11-18
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    • 2006
  • In the Internet of various networks, it is difficult to reduce real routing time by just minimizing their hop count. We propose an adaptive proximity route selection method in DHT-based peer-to-peer systems, in which nodes select the nぉe with smallest lookup latency among their routing table entries as a next routing node. Using Q-Routing algorithm and exponential recency-weighted average, each node estimates the total latency and establishes a lookup table. Moreover, without additional overhead, nodes exchange their lookup tables to update their routing tables. Several simulations measuring the lookup latencies and hop-to-hop latency show that our method outperforms the original Chord method as well as CFS' server selection method.

Experimental Study on Bearing Capacity of Ground Treated by Sand Compaction Piles (모래다짐말뚝(SCP) 시공지반의 지지력에 관한 실험적 연구)

  • 김병일;김영욱;이상익;최용성
    • Journal of the Korean Geotechnical Society
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    • v.20 no.4
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    • pp.39-47
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    • 2004
  • The SCP(sand compaction pile) method which is a vertical reinforcing technique for soft ground using a sand compaction pile has received increasing popularity in Korea. Currently, there are different methods to evaluate the bearing capacity of the reinforced ground by the SCP method. However, a method that can consider the effect of the replacement ratio on the bearing capacity is not yet available. This study investigated the effect of the replacement ratio on the bearing capacity of the reinforced ground by the SCP method. The study involved laboratory experiments which were conducted on a centrifuge facility. Test conditions included various ranges of replacement ratios (20, 30, and 40%), centrifuged consolidation, and loading. From the results of the study, a method which can evaluate the bearing capacity of the reinforced ground was proposed and verified using the weighted average of the replacement ratio.

Cluster Based Fuzzy Model Tree Using Node Information (상호 노드 정보를 이용한 클러스터 기반 퍼지 모델트리)

  • Park, Jin-Il;Lee, Dae-Jong;Kim, Yong-Sam;Cho, Young-Im;Chun, Myung-Geun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.18 no.1
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    • pp.41-47
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    • 2008
  • Cluster based fuzzy model tree has certain drawbacks to decrease performance of testinB data when over-fitting of training data exists. To reduce the sensitivity of performance due to over-fitting problem, we proposed a modified cluster based fuzzy model tree with node information. To construct model tree, cluster centers are calculated by fuzzy clustering method using all input and output attributes in advance. And then, linear models are constructed at internal nodes with fuzzy membership values between centers and input attributes. In the prediction step, membership values are calculated by using fuzzy distance between input attributes and all centers that passing the nodes from root to leaf nodes. Finally, data prediction is performed by the weighted average method with the linear models and fuzzy membership values. To show the effectiveness of the proposed method, we have applied our method to various dataset. Under various experiments, our proposed method shows better performance than conventional cluster based fuzzy model tree.

Implementing a Depth Map Generation Algorithm by Convolutional Neural Network (깊이맵 생성 알고리즘의 합성곱 신경망 구현)

  • Lee, Seungsoo;Kim, Hong Jin;Kim, Manbae
    • Journal of Broadcast Engineering
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    • v.23 no.1
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    • pp.3-10
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    • 2018
  • Depth map has been utilized in a varity of fields. Recently research on generating depth map by artificial neural network (ANN) has gained much interest. This paper validates the feasibility of implementing the ready-made depth map generation by convolutional neural network (CNN). First, for a given image, a depth map is generated by the weighted average of a saliency map as well as a motion history image. Then CNN network is trained by test images and depth maps. The objective and subjective experiments are performed on the CNN and showed that the CNN can replace the ready-made depth generation method.

Effects of Music Therapy on Agitation in Dementia: Systematic Review and Meta-analysis (음악요법이 치매의 초조행동에 미치는 효과: 체계적 문헌고찰 및 메타분석)

  • Kong, Eun-Hi;Park, Myonghwa
    • Korean Journal of Adult Nursing
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    • v.27 no.1
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    • pp.106-116
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    • 2015
  • Purpose: The purpose of this review was to assess the quality and to evaluate the effectiveness of music interventions in reducing agitation in older adults with dementia. Methods: Randomized controlled studies and randomized crossover studies were identified by searching MEDLINE, EMBASE, CINAHL, PsycINFO, AGELINE, Cochrane Central Register of Controlled Trials, Korea Med, Kmbase, RISS, National Assembly Digital Library, KISS, and RICH. Two reviewers independently retrieved articles, extracted data, and assessed the quality of studies. Results: In total, 10 studies were selected from 1095 unique citations. All included studies were conducted in long term care settings. Overall, risk of bias for included studies was low to moderate. The weighted average effect size across studies was -0.39 (95%CI [-0.69, -0.10], p=.009, $I^2=63%$). Music therapy was effective to reduce agitation of the older adults with dementia. Conclusion: Music intervention can be an effective non-pharmacological intervention for the reduction of agitation in dementia. Future studies need to use rigorous research method and to provide description of research methods in greater detail. In addition, future studies are required to explore the effects of music therapy according to severity of agitation and dementia.

Estimation of Design Flood Runoff in Ungaged Forest Watershed to Reduce Flood Damage within the National Park (국립공원내 홍수피해 저감을 위한 미계측 산림지역의 설계홍수량 추정)

  • Kim, Sang-Min;Im, Sang-Jun;Lee, Sang-Ho;Kim, Hyung-Ho;Ma, Ho-Seop;Jeong, Won-Ok
    • Journal of The Korean Society of Agricultural Engineers
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    • v.51 no.5
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    • pp.107-113
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    • 2009
  • The purpose of this study is to estimate the design flood runoff for ungaged forest watershed to reduce the flood damage in national park. Daewonsa watershed in Jirisan National Park was selected as study watershed, of which characteristic factors were obtained from GIS data. Flood runoff was simulated using SCS unit hydrograph module in HEC-HMS model. SCS Curve Number (CN) was calculated from forest type area weighted average method. Huff's time distribution of second-quartile storm of the Sancheong weather station, which is nearest from study watershed, was used for design flood runoff estimation. Critical storm duration for the study watershed was 3 hrs. Based on the critical duration, the peak runoff for each sub-watershed were simulated. It is recommended to monitor the long-term flow data for major stream stations in National Park for a better reliable peak runoff simulation results.

Noise Reduction Technique by Three-Points Ensemble Averaging in Uroflowmetry (삼점 신호 평균기법에 의한 요속신호의 잡음 축소 기법)

  • Choi, Seong-Su;Lee, In-Kwang;Lee, Sang-Bong;Park, Jun-Oh;Lee, Su-Ok;Cha, Eun-Jong;Kim, Kyung-Ah
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.8
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    • pp.1638-1643
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    • 2009
  • Uroflowmetry is a convenient clinical test to screen the benign prostatic hyperplasia(BPH) common in the aged men. A load cell is located beneath the urine container to measure the weight of urine. However, it is sensitive to the impact applied on the bottom of the container by the urine stream, which could be a noise source lowering the reliability of the system. With this aim, our study proposed a noise reduction technique by computing ensemble average of the weighted signals that were acquired from three-load cells forming a regular triangle beneath the urine container. Simulated urination experiment was performed with three different collection methods, all of which demonstrated significant noise reduction by ensemble averaging. Furthermore, the best results can be obtained without any special urine collection devices. Thus, our novel method can be usefully applied to uroflowmetry for enhancing measurement in terms of accuracy and reliability.

A Market-Based Replacement Cost Approach to Technology Valuation (기술가치평가를 위한 시장대체원가 접근법)

  • Kang, Pilsung;Geum, Youngjung;Park, Hyun-Woo;Kim, Sang-Gook;Sung, Tae-Eung;Lee, Hakyeon
    • Journal of Korean Institute of Industrial Engineers
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    • v.41 no.2
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    • pp.150-161
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    • 2015
  • This paper proposes a new approach to technology valuation, the market-replacement cost approach which integrates the cost-based approach and market-based approach. The proposed approach estimates the market-replacement cost of a target technology using R&D costs of similar R&D projects previously conducted. Similar R&D projects are extracted from project database based on document similarity between project proposals and technology description of the target technology. R&D costs of similar R&D projects are adjusted by mirroring the rate of technological obsolescence and inflation. Market-replacement cost of the technology is then derived by calculating the weighted average of adjusted costs and similarity values of similar R&D projects. A case of "Prevention method and system for the diffusion of mobile malicious code" is presented to illustrate the proposed approach.

A Study on the Geometric Correction of a CCD Camera Scanner Using the Exterior Orientation Parameters (외부표정요소를 이용한 CCD 카메라 스캐너의 기하학적 왜곡 보정기법 연구)

  • 안기원;문명상
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.11 no.2
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    • pp.69-77
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    • 1993
  • Investigation is given to the detailed procedure of a computer assisted automatic correction for scanning errors of the digital images of close-range photographs scanned by the CCD camera scanner. After determination of the exterior orientation parameters, photo coordinates of the all pixels were calculated using collinearity equation. For the generation of geometric corrected image from the photo coordinates of the all pixels, inverse-weighted-distance average method was used. And the accuracy of the resulting new image was checked comparing its image coordinates with there corresponding ground coordinates for the check points.

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