• 제목/요약/키워드: Loss combination

검색결과 673건 처리시간 0.024초

Nano-scale Inter-lamellar Structure of Metal Powder Composites for High Performance Power Inductor and Motor Applications

  • Kim, Hakkwan;An, Sung Yong
    • Journal of Magnetics
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    • 제20권2호
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    • pp.138-147
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    • 2015
  • The unique nano-scale inter-lamellar microstructure and unparalleled heat treatment process give our developed metal powder composite its outstanding magnetic property for power inductor & motor applications. Compared to the conventional polycrystalline Fe or amorphous Fe-Cr-Si-B alloys, our unique designed inter-lamellar microstructure strongly decreases the intra-particle eddy current loss at high frequencies by blocking the mutual eddy currents. The combination of optimum permeability, magnetic flux and extremely low core loss makes this powder composite suitable for high frequency applications well above 10 MHz. Moreover, it can be also possible to SMC core for high speed motor applications in order to increase the motor efficiency by decreasing the core loss.

합성곱 신경망 기반 밝기-색상 정보를 이용한 얼굴 위변조 검출 방법 (Face Anti-Spoofing Based on Combination of Luminance and Chrominance with Convolutional Neural Networks)

  • 김은석;김원준
    • 방송공학회논문지
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    • 제24권6호
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    • pp.1113-1121
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    • 2019
  • 본 논문에서는 얼굴의 밝기와 색상 정보를 함께 이용한 합성곱 신경망 기반의 얼굴 위변조 검출 방법을 제안한다. 제안하는 방법은 적층된 합성곱 신경망과 보조 신경망을 이용하여 실제 얼굴과 위변조된 얼굴의 밝기 특징과 색상 특징을 독립적으로 추출한다. 기존의 방법과는 달리, 본 논문에서는 추출된 특징을 단순 결합(Concatenation)하는 것이 아니라 주의 모듈(Attention Module)을 이용하여 적응적(Adaptively)으로 조합할 수 있도록 하였다. 또한, 효과적인 분류기 학습을 위하여 대비 손실함수(Contrast Loss Function)를 새롭게 제안하였는데, 대비 손실함수는 동일 클래스 내의 특징 간의 차이는 최소화 시키고 서로 다른 클래스의 특징 간의 차이는 최대화 시킴으로써 특징의 분별력을 높인다. 다양한 실험을 통해 본 논문에서 제안하는 방법이 기존 얼굴 위변조 검출 방법 대비 개선된 성능을 보임을 확인하고 그 결과를 분석한다.

흉부 볼륨 CT영상에서 Weighted Integration Loss을 이용한 폐암 분할 알고리즘 연구 (A Study on Lung Cancer Segmentation Algorithm using Weighted Integration Loss on Volumetric Chest CT Image)

  • 정진교;김영재;김광기
    • 한국멀티미디어학회논문지
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    • 제23권5호
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    • pp.625-632
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    • 2020
  • In the diagnosis of lung cancer, the tumor size is measured by the longest diameter of the tumor in the entire slice of the CT. In order to accurately estimate the size of the tumor, it is better to measure the volume, but there are some limitations in calculating the volume in the clinic. In this study, we propose an algorithm to segment lung cancer by applying a custom loss function that combines focal loss and dice loss to a U-Net model that shows high performance in segmentation problems in chest CT images. The combination of values of the various parameters in custom loss function was compared to the results of the model learned. The purposed loss function showed F1 score of 88.77%, precision of 87.31%, recall of 90.30% and average precision of 0.827 at α=0.25, γ=4, β=0.7. The performance of the proposed custom loss function showed good performance in lung cancer segmentation.

저가형 GPS와 INS를 이용한 복합항법 시스템 개발 (Integrated Navigation System with Low-cost GPS and INS)

  • 김민호;송현민;김정래
    • 항공우주시스템공학회지
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    • 제4권3호
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    • pp.17-23
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    • 2010
  • GPS sensors provide accurate position and velocity of moving vehicles. However, GPS is weak at intermittent signal loss and large position error. Combination with INS improves the GPS position accuracy during the GPS signal loss. In this paper, a fusion filter using GPS and INS is developed and its perfomance is analyzed with RC car and RC airplane experiments.

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흡음재가 부착된 직방형 소음기의 전달 손실 예측 (Prediction of transmission loss of parallelepiped plenum chambers with liner)

  • 김회전;이정권;박철민
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.383-386
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    • 2003
  • This paper deals with transmission loss of 3-dimensional rectangular plenum lined chamber. There are three kinds of rectangular plenum lined chamber: throughflow type, flow-reversal type, and end-in/side-out type. The combination of above three types of rectangular plenum lined chamber is used for the commercial HVAC system and automobile exhaust system. However, the ambiguity and complexity of sound absorbing material property and 3-dimensional property have impeded research. In this paper, the transmission loss of three kinds of rectangular plenum lined chamber is derived and calculated. The effect of increase of sound absorbing material is also considered. Analytical solution is calculated by using the locally-reacting property of sound absorbing material.

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누설자속에 의한 대용량 변압기의 권선지지구조 및 외함의 와전류손실 계산에 관한 연구 (The Loss Calculation of Eddy Current of the Tank and Winding Supports in Transformers by the Leakage Flux)

  • 허우행;이동엽;김규탁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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    • pp.948-950
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    • 2005
  • This paper compared the test data with the loss when a conductor is exposed to the magnetic fieldof reactors after generating external magnetic field in specimen by means of an air core reactor model and the calculation of loss came from a tying the combination of FEM and integral method. It was applied to the loss measurement of transformers due to leakage flux.

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비압축성 재생형 기계에 대한 개선된 운동량 교환 이론 (II) - 손실 모델 및 성능 예측 - (Improved Momentum Exchange Theory for Incompressible Regenerative Turbomachines (II) - Loss Model and Performance Prediction -)

  • 박무룡;정명균;유일수
    • 대한기계학회논문집B
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    • 제28권10호
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    • pp.1247-1254
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    • 2004
  • In momentum exchange theory the loss models for the circulatory flow is critically important. But because of lack of loss model on the circulatory flow, analysis model on regenerative turbomachines is not available in the open literature. In the present study circulatory loss is evaluated by combining bend's losses. Through the comparison with the previous experimental data on linear pressure gradient, a combination factor is suggested in terms of the aspect ratio of a channel. Applying this factor to two kinds of regenerative blowers the predicted results are found to be in good agreement with the experimental data of the overall performance and the head distribution along the rotational direction. Especially, the comparison with the head distribution demonstrates the accuracy of hydraulic model and loss model suggested in the present study. And the comparison with the overall performance confirms the validness of physical models as well as loss models suggested in the present study.

경구용 생약 복합 조성물과 경피용 육모 조성물의 복합 사용에 따른 육모 상승 효과 (Synergistic Effects of the Combination of Oral Herbal Composition and Topical Hair Tonic on Hair Growth in C57BL6 Mice)

  • 전희영;김승훈;신현정;서대방;이상준
    • 한국식품과학회지
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    • 제44권2호
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    • pp.257-262
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    • 2012
  • 본 연구에서는 경구용과 경피용 육모 조성물의 병용 사용에 따른 육모 상승효과를 평가하기 위하여 C57BL/6 model을 이용하여 검은콩을 포함한 경구용 생약 복합 조성물과 탈모 방지 의약외품의 주요 효능 조성물로 구성된 경피용 육모 조성물의 복합사용에 따른 육모 상승 효과를 평가하였다. 그 결과 경구용 생약복합물을 섭취하거나 경피용 외용제외 도포하였을 때 성장기 모낭을 유도하여 모발의 성장을 촉진시키는 효과가 유사하게 나타나는 것을 확인하였고, 이 두 가지 방법을 병용하였을 때 그 효과가 더욱 상승하는 것을 관찰 할 수 있었다. 이러한 상승 효과는 외용제에서 나타나지 않은 경구제의 혈액 지표 개선 효과가 두 방법을 복합 사용할 경우 더해지기 때문인 것으로 추정된다. 경구제와 외용제의 병용에 따른 상승 효과를 확신하고 그 작용기전을 규명하기 위해서는 $5{\alpha}$-reductase를 비롯하여 탈모의 원인이 되는 다른 지표들의 변화를 평가하고, 이러한 효과가 인체를 대상으로 하였을 때도 나타나는지 확인하는 연구가 후속되어야 할 것이다. 또한 본 연구에서 사용된 조성물의 특이적인 효과가 아님을 확인하기 위하여 다양한 물질을 이용한 평가가 검증 연구가 필요할 것이다. 그러나 본 연구는 그간 막연하게 사용하였던 경구제와 외용제의 복합적인 사용이 기전적으로 구분되어 상승 효과를 가지는 것을 실험적으로 확인하였다는 것에 의의가 있으며 본 연구 결과를 바탕으로 탈모 치료법의 적절한 병용을 통하여 보다 나은 탈모 치료 효과를 기대할 수 있을 것이다.

Protective Effect of Brazilin on Cisplatin Nephrotoxicity

  • Kong, Jae-Myeong;Seo, Kyung-Won;Choung, Se-Young
    • Biomolecules & Therapeutics
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    • 제2권2호
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    • pp.103-107
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    • 1994
  • Cisplatin is one of the most effective antitumor agents currently available for cancer therapy. However, its clinical use has been limited by its severe side effects, especially nephrotoxicity. Therefore, brazilin, which has a radical scavenging effect, was given intraperitoneally to evaluate the effect on cisplatin nephrotoxicity in rats. Remarkable protective effects against nephrotoxicity of cisplatin were observed when brazilin was administered to rats simultaneously with cisplatin. Hepatotoxicity induced by combination treatment of cisplatin and brazilin was evaluated by measuring serum glutamic pyruvate transaminase and serum glutamic oxalate transaminase. Combination treatment did not affect the levels of sGPT and SGOT, and any combination treatment did not induce metallothionein in kidney. Brazilin which has radical scavenging effect directly reduced nephrotoxicity of wisplatin in vivo. Thus, it seems that nephrotoxicity of cisplatin was caused by free radicals. The present results Indicate that brazilin, when it is given with cisplatin, may provide protection against cisplatin nephrotoxicity in rats.

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Optimizing the Combination of Smoking and Boiling on Quality of Korean Traditional Boiled Loin (M. longissimus dorsi)

  • Choi, Yun-Sang;Kim, Hyun-Wook;Hwang, Ko-Eun;Song, Dong-Heon;Kim, Yong-Jae;Jung, Tae-Jun;Kim, Young-Boong;Kim, Cheon-Jei
    • 한국축산식품학회지
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    • 제35권2호
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    • pp.149-155
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    • 2015
  • The combined effects of smoking and boiling on the proximate composition, technological quality traits, shear force, and sensory characteristics of the Korean traditional boiled loin were studied. Cooking loss, processing loss, and shear force were lower in the smoked/ boiled samples than those in the control (without smoking treatment) (p<0.05). The results showed that the boiled loin samples between the control and treatment did not differ significantly in protein, fat, or ash contents, or pH values (p>0.05). The treated samples had higher score for overall acceptability than the control (p<0.05). Thus, these results show that the Korean traditional boiled loin treated with smoking for 60 min before boiling had improved physicochemical properties and sensory characteristics.