• 제목/요약/키워드: Rapid Convergence

검색결과 998건 처리시간 0.033초

결정함수 가변스텝 LMS 알고리즘 (Deterministic Function Variable Step Size LMS Algorithm)

  • 우홍체
    • 융합신호처리학회논문지
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    • 제12권2호
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    • pp.128-132
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    • 2011
  • LMS(Least mean square) 적응 알고리즘은 radar, sonar, 음성처리, 이동통신 분야 등에서 중요한 역할을 하고 있다. 이동통신 분야에서는 LMS 적응 알고리즘의 빠른 수렴속도가 더욱 중요하다. 하지만 LMS 알고리즘은 수렴속도가 느리고 일정치 않은 수렴을 하는 문제점을 가지고 있다. 이러한 문제점을 해결하기 위하여 다양한 가변 스텝 LMS 적응 알고리즘들이 최근에 많이 연구되어왔다. 연구된 많은 LMS 알고리즘들은 빠른 수렴속도를 얻기 위하여 복잡한 가변스텝방식을 사용하는데 이는 많은 계산량을 필요로 한다. 따라서 LMS 알고리즘의 최대 장점인 단순성과 강인성을 약화시킨다. 제안하는 결정함수 가변스텝 LMS 알고리즘은 스텝 값을 간단한 결정함수에 따라 결정하므로 단순성을 최대한 강화하면서 빠른 수렴속도를 얻도록 한다.

Control strategies of energy storage limiting intermittent output of solar power generation: Planning and evaluation for participation in electricity market

  • Sewan Heo;Jinsoo Han;Wan-Ki Park
    • ETRI Journal
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    • 제45권4호
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    • pp.636-649
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    • 2023
  • Renewable energy generation cannot be consistently predicted or controlled. Therefore, it is currently not widely used in the electricity market, which requires dependable production. In this study, reliability- and variance-based controls of energy storage strategies are proposed to utilize renewable energy as a steady contributor to the electricity market. For reliability-based control, photovoltaic (PV) generation is assumed to be registered in the power generation plan. PV generation yields a reliable output using energy storage units to compensate for PV prediction errors. We also propose a runtime state-ofcharge management method for sustainable operations. With variance-based controls, changes in rapid power generation are limited through ramp rate control. This study introduces new reliability and variance indices as indicators for evaluating these strategies. The reliability index quantifies the degree to which the actual generation realizes the plan, and the variance index quantifies the degree of power change. The two strategies are verified based on simulations and experiments. The reliability index improved by 3.1 times on average over 21 days at a real power plant.

EER-ASSL: Combining Rollback Learning and Deep Learning for Rapid Adaptive Object Detection

  • Ahmed, Minhaz Uddin;Kim, Yeong Hyeon;Rhee, Phill Kyu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권12호
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    • pp.4776-4794
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    • 2020
  • We propose a rapid adaptive learning framework for streaming object detection, called EER-ASSL. The method combines the expected error reduction (EER) dependent rollback learning and the active semi-supervised learning (ASSL) for a rapid adaptive CNN detector. Most CNN object detectors are built on the assumption of static data distribution. However, images are often noisy and biased, and the data distribution is imbalanced in a real world environment. The proposed method consists of collaborative sampling and EER-ASSL. The EER-ASSL utilizes the active learning (AL) and rollback based semi-supervised learning (SSL). The AL allows us to select more informative and representative samples measuring uncertainty and diversity. The SSL divides the selected streaming image samples into the bins and each bin repeatedly transfers the discriminative knowledge of the EER and CNN models to the next bin until convergence and incorporation with the EER rollback learning algorithm is achieved. The EER models provide a rapid short-term myopic adaptation and the CNN models an incremental long-term performance improvement. EER-ASSL can overcome noisy and biased labels in varying data distribution. Extensive experiments shows that EER-ASSL obtained 70.9 mAP compared to state-of-the-art technology such as Faster RCNN, SSD300, and YOLOv2.

인플루엔자 바이러스에 대한 신속 항원 검출 검사 검출한계의 융합적 분석 (Fusion Analytical Sensitivity of Rapid Influenza Antigen Limit of Detection Tests for Human Influenza virus)

  • 송창섭;성현호;김정현;김대은;박창은;윤중수
    • 한국융합학회논문지
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    • 제9권3호
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    • pp.165-171
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    • 2018
  • 본 논문은 국내 인플루엔자 신속항원검사키트의 민감도의 검출한계를 분석하기위하여 국내 시판중인 인플루엔자 신속항원검사키트 5종을 대상으로 인플루엔자 바이러스 A형과 B형 배양액을 연속 희석하여 양성 검출 한계를 분석하였다. 분석 결과 A형의 육안측정결과는 웰스바이오 제품은 1:8192까지, II제품은 1:4096까지, I과 III제품은 1:512까지, IV제품은 1:128에서만 양성이 확인되었고, B형 육안측정결과는 웰스바이오 제품이 1:8192까지, II제품은 1:4096까지, I, III, IV제품의 경우 1:1024까지 양성이 확인되었다. 같은 검체의 기기 판독의 경우 A형, B형 모두 웰스바이오 제품이 1:8192까지, II제품이 1:4096까지, I제품은 1:2048까지 양성으로 확인되었다. 인플루엔자 신속항원검사의 민감도는 환자의 검체 채취부위 및 감염기간, 검체의 양 등에 따라 많은 차이가 있으므로, 검체의 채취시기 및 방법 등을 정확하게 준수해야할 것이며, 신속항원검사 키트의 민감도를 높이기 위한 다각적인 연구가 필요할 것으로 사료된다.

E-빔 증착된 Sn 전구체의 황화 열처리 온도 및 시간에 따른 SnSx 박막 성장 효과 (Effect of the Sulfurization Temperature and Annealing Time of E-Beam Evaporated Sn Precursors on the Growth of SnSx Thin Films)

  • 황팅지엔;김제하
    • 한국전기전자재료학회논문지
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    • 제30권11호
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    • pp.734-739
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    • 2017
  • We prepared $SnS_x$ thin films on both soda-lime glass (SLG) and molybdenum(Mo)/SLG substrates by a two-step process using a Sn precursor followed by sulfur reaction in rapid thermal annealing (RTA) at different sulfurization temperatures ($Ts=200^{\circ}C$, $230^{\circ}C$, $250^{\circ}C$, and $300^{\circ}C$) and annealing times ($t_s=10min$ and 30 min). The single SnS phase was dominant for $200^{\circ}C{\leq}T_s$<$250^{\circ}C$, while an additional phase of $SnS_2$ was appeared at $T_s{\geq}250^{\circ}C$ alongside SnS. The SnS grains in all the samples showed strong growth along the preferred [040] direction. The band-gap energy ($E_g$) of the films was estimated to be 1.24 eV.

Kompsat-3A 영상에서 팔당댐 유역의 하천과 저류지의 분할에 관한 연구 (A Study on the Stream and Reservoir Segmentation in Paldang Dam Basin in Kompsat-3A Image)

  • 유호진;최현
    • 한국산업융합학회 논문집
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    • 제23권2_2호
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    • pp.173-180
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    • 2020
  • In Korea, due to the rapid increase in population due to industrialization, rivers were developed and managed with a focus on the completion and dimension of rivers. Due to the rapid increase in river use, there are so many river facilities indiscriminately that the administrative and management tasks are complicated and diversified in computerizing facilities and hydrologic data. Many methods have been proposed to solve this problem, but many problems exist. Among them, water has the same spectral characteristics, so it is difficult to subdivide into rivers, reservoirs, and dams. Therefore, this study subdivided the water system using supervised classification and GIS in order to efficiently manage the water resources by classifying the water system with the same spectral characteristics. In order to analyze the accuracy of the results, the accuracy of the objects classified using land cover map provided by environmental spatial information service was evaluated, and the result was an average of 91.75%, with 97.50% of rivers, 87.76% of reservoirs, and 90.00% of others.

무인항공기를 활용한 정사영상제작에서 지상기준점 위치간격과 비행촬영기법에 따른 정사영상정확도 향상에 관한 연구 (A Study on the Improvement of Orthophoto Accuracy According to the Flight Photographing Technique and GCP Location Distance in Orthophoto Generation Using UAV)

  • 윤부열;윤원섭
    • 한국산업융합학회 논문집
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    • 제21권6호
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    • pp.345-354
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    • 2018
  • It is conservative to say that lots of research is performed as measures to use UAV for application to the rapid spatial information and its application is faced with settlement stage to some extent. In addition, Korea Land and Geospatial Informatix Corporation autonomously produces work regulation which is applied to every kind of orders and National Geographic Information Institute (2018) has notified public surveying work instructions about unmanned aerial device for the rapid spatial information construction. The results acquired by UAV are comprised of contents about accuracy improvements for the orthophoto when reviewing pertinent regulations. The results acquired by UAV are comprised of contents about accuracy improvements for the orthophoto when reviewing pertinent regulations. As a result, it is known that error amount has been sharply increased from 400m separation distance, and this study proposes that cross flight is able to reduce irregular error occurrence as measures to acquire stable results.

Analysis of external environmental factors affecting patient transport time

  • LEE, Hyeryeong;PARK, Sang Woong;YUN, Eunjeong;KIM, Dakyeong;CHOI, Hea Kyung
    • 식품보건융합연구
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    • 제8권6호
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    • pp.11-17
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    • 2022
  • Emergency transport is directly related to the life of the patient, and rapid transport to the hospital is crucial. However, external environmental factors such as traffic or weather, interfere with hospital transport. In this study, we investigated the external environment affecting hospital transport time. We examined the transfer time and patient treatment time of emergency patients in an area of northern Gyeonggi-do from 2018 to 2020. Diagnosis after arrival at the hospital was used, and on-site treatment time was measured from paramedic arrival time at the scene to departure. Furthermore, we examined whether there was a correlation between the time paramedics left the scene and hospital arrival time through the reason for the delay as recorded in the emergency log. Traffic jams had the greatest impact on patient transport, while transport delays occurred due to heavy rain, but not snow. Among injured patients, electrical accidents were the most problematic in terms of on-site treatment time. This was because a lot of first aid is needed in electrical accidents. It must be necessary to mobilize two ambulances in an emergency through the expansion of infrastructure, prepare a plan for rapid transport in heavy rain, and implement strong laws against transport obstruction.

Proposed ICT-based New Normal Smart Care System Model to Close Health Gap for Older the Elderly

  • YOO, Chae-Hyun;SHIN, Seung-Jung
    • International journal of advanced smart convergence
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    • 제10권2호
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    • pp.37-44
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    • 2021
  • At the time of entering the super-aged society, the health problem of the elderly is becoming more prominent due to the rapid digital era caused by COVID-19, but the gap between welfare budgets and welfare benefits according to regional characteristics is still not narrowed and there is a significant difference in emergency medical access. In response, this study proposes an ICT-based New Normal Smart Care System (NNSCS) to bridge the gap I n health and medical problems. This is an integrated system model that links the elderly themselves to health care, self-diagnosis, disease prediction and prevention, and emergency medical services. The purpose is to apply location-based technology and motion recognition technology under smartphones and smartwatches (wearable) environments to detect health care and risks, predict and diagnose diseases using health and medical big data, and minimize treatment latency. Through the New Normal Smart Care System (NNSCS), which links health care, prevention, and rapid emergency treatment with easy and simple access to health care for the elderly, it aims to minimize health gaps and solve health problems for the elderly.