• 제목/요약/키워드: Short Baseline

검색결과 274건 처리시간 0.025초

Aspect-Based Sentiment Analysis with Position Embedding Interactive Attention Network

  • Xiang, Yan;Zhang, Jiqun;Zhang, Zhoubin;Yu, Zhengtao;Xian, Yantuan
    • Journal of Information Processing Systems
    • /
    • 제18권5호
    • /
    • pp.614-627
    • /
    • 2022
  • Aspect-based sentiment analysis is to discover the sentiment polarity towards an aspect from user-generated natural language. So far, most of the methods only use the implicit position information of the aspect in the context, instead of directly utilizing the position relationship between the aspect and the sentiment terms. In fact, neighboring words of the aspect terms should be given more attention than other words in the context. This paper studies the influence of different position embedding methods on the sentimental polarities of given aspects, and proposes a position embedding interactive attention network based on a long short-term memory network. Firstly, it uses the position information of the context simultaneously in the input layer and the attention layer. Secondly, it mines the importance of different context words for the aspect with the interactive attention mechanism. Finally, it generates a valid representation of the aspect and the context for sentiment classification. The model which has been posed was evaluated on the datasets of the Semantic Evaluation 2014. Compared with other baseline models, the accuracy of our model increases by about 2% on the restaurant dataset and 1% on the laptop dataset.

폐암 환자의 정위체부방사선치료 시 기준선 변화에 따른 3D-CBCT(Cone Beam Computed-Tomography)와 Gated-CBCT의 영상 품질 및 유용성 평가 (Image quality and usefulness evaluaton of 3D-CBCT and Gated-CBCT according to baseline changes for SBRT of Lung Cancer)

  • 한국희;신충훈;이충환;유순미;박자람;김진수;윤인하
    • 대한방사선치료학회지
    • /
    • 제35권
    • /
    • pp.41-51
    • /
    • 2023
  • 목 적: 본 연구는 폐암 환자의 정위체부방사선치료 시(Stereotactic Body Radiation Therapy, SBRT) 기준선(Baseline) 변화에 따른 3D-CBCT(Cone Beam Computed-Tomography)와 Gated-CBCT의 영상 품질(Image quality)을 비교 분석하여 호흡에 따른 움직임의 보정에 유용한 CBCT 촬영 방법을 찾고자 한다. 대상 및 방법: QUASARTM(Modus Medical Devices Inc, Canada) 팬텀에 지름이 3 cm인 고체 종양 물질(Solid Tumor)을 삽입하여 팬텀의 속도를 주기 3 sec, 최대 진폭 20 mm 로 4DCT(4-Dimentional Computed-Tomography)를 촬영하였다. 전산화 치료계획시스템 EclipseTM을 이용하여 고체 종양 물질에 육안적 종양용적(Gross Target Volume, GTV)을 윤곽 묘사하였다. Truebeam STxTM을 이용해 4DCT 촬영 시와 동일하게 설정한 후, 기준선 변화가 1 mm, 3 mm, 5 mm인 호흡 패턴을 팬텀에 입력하여 3D-CBCT(Spotlight, Full)와 Gated-CBCT(Spotlight, Full) 영상을 5회 반복하여 획득하였다. 획득된 영상을 4DCT 영상을 기준으로 신호대잡음비(Signal-to-Noise Ratio, SNR), 대조대잡음비(Contrast-to-Noise Ratio, CNR), 종양 체적 길이(Tumor Volume Length) 및 모션 블러링 비(Motion Blurring Ratio, MBR)를 측정하여 비교하였다. 결 과: Spotlight Gated-CBCT 영상이 기준선 변화에 따른 신호대잡음비가 평균 13.30±0.10%, 대조대잡음비가 평균 7.78±0.16%, 종양 체적 길이가 평균 3.55 ± 0.17%, 모션 블러링 비가 평균 1.18 ± 0.06%로 Spotlight 3D-CBCT보다 우수한 값을 보였다. 또한, Full Gated-CBCT 영상이 기준선 변화에 따른 신호대잡음비가 평균 12.80 ± 0.11%, 대조대잡음비가 평균 7.60 ± 0.11%, 종양 체적 길이가 평균 3.54 ± 0.16%, 모션 블러링 비가 평균 1.18 ± 0.05%로 Full 3D-CBCT보다 우수한 값을 보였다. 결 론: 3D-CBCT 촬영 영상과 비교하여 Gated-CBCT 촬영 영상이 기준선 변화에 따른 영상 품질이 우수한 값을 보였으며, 호흡으로 인한 모션 블러링 인공물(Motion Blurring Artifacts)의 영향이 적은 것을 확인했다. 따라서 단기간에 고선량을 전달하는 폐암의 정위체부방사선치료 시 불규칙한 호흡으로 인한 기준선 변화가 발생하는 경우 Gated-CBCT를 이용해 영상유도(Image Guide)를 하는 것이 유용하다고 판단된다.

  • PDF

Cone-beam CT를 이용한 골격성 III급 부정교합자의 하악골 후퇴술 후 상기도 변화에 관한 연구 (Three dimensional cone-beam CT study of upper airway change after mandibular setback surgery for skeletal Class III malocclusion patients)

  • 김나리;김용일;박수병;황대석
    • 대한치과교정학회지
    • /
    • 제40권3호
    • /
    • pp.145-155
    • /
    • 2010
  • 악교정 수술은 안면골격형태 뿐만 아니라 상기도 공간에도 영향을 준다. 본 연구는 골격성 III급 부정교합자 중 하악골 후퇴술을 시행 받은 환자를 대상으로 상기도 공간의 부피변화를 관찰하기 위하여 시행되었다. 기존의 연구들이 측모두부방사선사진을 중심으로 시행하였으나 본 연구에서는 3차원 cone-beam computed tomography (CBCT)를 이용하여 영상을 재구성한 뒤 분석하였다. 연구 대상은 하악골 후퇴술을 시행 받은 20명(남성 12, 여성 8)이었으며, 수술 전 평균 1.8주(Baseline), 술 후 평균 2.3개월(T1) 그리고 술 후 평균 1년(T2) 시기에 CBCT를 촬영하였다. 상기도공간은 기준평면에 따라 비인두, 구인두, 하인두로 나누어 계측하고 Baseline, T1, T2를 각각 비교하였다. 결과로 수술 후 2.3개월(T1)시기에 상기도 공간은 상당히 감소하였으며 (p < 0.001), 술 후 1년 후(T2)에도 감소된 양은 증가하지 않았다. 구인두는 상기도 공간 중 가장 많은 감소폭을 보였다. 이러한 결과로 하악골후퇴술은 상기도 공간을 장 단기간동안 감소하는 것으로 나타났다.

기선 거리에 따른 이동체의 N-RTK 위치정확도 평가 (Evaluation of N-RTK Positioning Accuracy for Moving Platform)

  • 김민서;배태석
    • 한국측량학회지
    • /
    • 제38권3호
    • /
    • pp.259-267
    • /
    • 2020
  • 실시간 정밀 위치결정을 위해서 N-RTK (Network Real-Time Kinematic) 기술이 많이 사용되고 있다. 하지만 기존의 N-RTK 시스템은 사용자 수 제한으로 인해 지속해서 늘어나는 무인 이동체의 위치결정을 하는 데 한계가 있다. 따라서 사용자 수 제한 없이 보정 신호를 생성하는 시스템이 있다면 어느 정도의 간격으로 있어야 전국어디에서든 위치결정을 할 수 있을지에 대한 연구가 필요할 것으로 판단하여 기선 거리에 따른 N-RTK 시스템의 정확도를 분석하였다. 다양한 장비를 사용하는 사용자들이 있을 것으로 예상하여 서로 다른 성능의 수신기로 로버 위치를 추정하였으며, 자료처리는 오픈소스 소프트웨어인 RTKLIB을 활용하였다. 실험 결과, 로버와 가장 가까운 기준국에서는 수신기의 종류와 관계없이 높은 비율로 고정해가 산출되었으며, 추정 좌표의 정확도 역시 비슷한 수준으로 결정되었다. 로버에서 약 40km 떨어져 있는 기준국 보정 신호를 활용하는 경우, 고정해 산출 비율은 평균 약 50% 정도 감소하였으나 수직 RMSE (Root Mean Squared Error)는 약 2.5-4.7cm로 단기선 결과(1.0-1.5cm)와 크게 다르지 않았다. 고가형 수신기는 장기선에서도 이상값(outlier) 크게 나타나지 않았으며, 향후 과학기술용 정밀 자료 처리 소프트웨어를 활용한 고정해 산출과 좌표 추정 정확도에 대한 분석을 수행할 예정이다.

단기 호르몬 병합 치료가 폐경 후 우울증 환자의 인지 기능에 미치는 영향 (The Effect of Hormone Replacement Therapy for Cognitive Function of Postmenopausal Depression)

  • 이상훈;고영훈;조숙행;정인과;김승현;이문수
    • 생물정신의학
    • /
    • 제12권2호
    • /
    • pp.173-180
    • /
    • 2005
  • Purpose:We investigated the effect of menopausal duration on cognitive function using adjunctive hormone replacement therapy(HRT) in postmenopausal women with depression. Method:Twelve postmenopausal women with depressive disorder were enrolled. Six patients having menopausal duration of less than 3 years was assigned to the short duration group and six patients of more than 3 years to the long duration group. Each patient was treated with conjugated equine estrogen(1.25mg) plus medroxyprogesterone(5mg) for 8 weeks. Cognitive performance was measured by the Verbal Memory Test, Visual Memory Test, Trail Making Test, Digit Symbol Test, and Attention Shift Test. The Beck Depression Inventory was used for evaluation of depressed mood. The reproductive hormone levels were also measured. Results:The long duration group showed the lower performance only in Trail Making Test B compared with the short duration group at baseline. After 8 weeks, the long duration group performed significantly better in the Trail Making Test B compared with the short duration group. The differences in change of depressive mood and gonadal hormone level between two groups were not significant. Conclusion:Menopausal duration before HRT may influence the effect of estrogen on cognition in some cognitive domains. This might be related with estrogen receptor hypersensitivity which induced by the longer estrogen deficiency.

  • PDF

A short education session increases the accuracy of estimated food records in young Korean women during a controlled-feeding study

  • Kim, Seunghee;Lee, Bora;Park, Clara Yongjoo
    • Nutrition Research and Practice
    • /
    • 제15권5호
    • /
    • pp.613-627
    • /
    • 2021
  • BACKGROUND/OBJECTIVES: Despite the widespread use of dietary assessment tools, the validity of food records has not been evaluated in Koreans. We assessed the accuracy of estimated food records and the effect of a short education session in young Korean women. SUBJECTS/METHODS: Thirty women (aged 18-23 yrs) each completed 3 food records during a controlled-feeding study. One educational session was provided on day 2 of the study. Food records were analyzed for the accuracy of food items and portion size estimation according to food group (grains; meat, fish, eggs, and beans; vegetables; fruit; dairy; and oils and sugars) and type of dish (rice, kimchi, soup, side dishes, spreads, beverages, and snacks). Reported food items were categorized as exact, close, or far matches, exclusions, or intrusions. Portion sizes were evaluated as accurate, similar, or inaccurate estimates, or missing. The means of days 2 and 3 were used to assess post-education results. Paired t-tests were performed to assess the effects of the education session. RESULTS: The mean percentages of exact matches, close matches, far matches, and exclusions on day 1 were 80.9%, 10.9%, 2.0%, and 6.2%, respectively, and mean intrusions observed were 0.1. The education session slightly increased the accuracy of recorded food items. The percentages of accurate, similar, and inaccurate estimates, and missing portion sizes were 11.7%, 19.8%, 12.2%, and 56.3%, respectively, at baseline. The percentage of missing portion size estimates decreased to 14.0% after the education session, resulting in an increase in the percentages of all other estimates. An increase was observed in the accuracy of reported portion sizes of vegetables, rice, and kimchi. CONCLUSIONS: In young Korean women, estimated food records are highly accurate for food items but not for portion size estimates without prior education. A short education session can improve the accuracy of portion size estimation.

The Dome Technique for Managing Massive Anterosuperior Medial Acetabular Bone Loss in Revision Total Hip Arthroplasty: Short-Term Outcomes

  • Tyler J. Humphrey;Colin M. Baker;Paul M. Courtney;Wayne G. Paprosky;Hany S. Bedair;Neil P. Sheth;Christopher M. Melnic
    • Hip & pelvis
    • /
    • 제35권2호
    • /
    • pp.122-132
    • /
    • 2023
  • Purpose: The dome technique is a technique used in performance of revision total hip arthroplasty (THA) involving intraoperative joining of two porous metal acetabular augments to fill a massive anterosuperior medial acetabular bone defect. While excellent outcomes were achieved using this surgical technique in a series of three cases, short-term results have not been reported. We hypothesized that excellent short-term clinical and patient reported outcomes could be achieved with use of the dome technique. Materials and Methods: A multicenter case series was conducted for evaluation of patients who underwent revision THA using the dome technique for management of Paprosky 3B anterosuperior medial acetabular bone loss from 2013-2019 with a minimum clinical follow-up period of two years. Twelve cases in 12 patients were identified. Baseline demographics, intraoperative variables, surgical outcomes, and patient reported outcomes were acquired. Results: The implant survivorship was 91% with component failure requiring re-revision in only one patient at a mean follow-up period of 36.2 months (range, 24-72 months). Three patients (25.0%) experienced complications, including re-revision for component failure, inter-prosthetic dual-mobility dissociation, and periprosthetic joint infection. Of seven patients who completed the HOOS, JR (hip disability and osteoarthritis outcome score, joint replacement) survey, five patients showed improvement. Conclusion: Excellent outcomes can be achieved using the dome technique for management of massive anterosuperior medial acetabular defects in revision THA with survivorship of 91% at a mean follow-up period of three years. Conduct of future studies will be required in order to evaluate mid- to long-term outcomes for this technique.

GPS의 변위 검출 능력에 대한 실험 (A test on deformation detection ability of GPS)

  • 박필호;박종욱;조정호;전경수;조성호
    • 한국측량학회지
    • /
    • 제17권2호
    • /
    • pp.161-166
    • /
    • 1999
  • 3축 방향의 이동이 가능한 GPS 시험대의 실제 이동량을 GPS가 어느 정도 정확하게 검출해 내는가를 분석하여 GPS의 변위검출 능력을 실험적으로 검증하였다. 그 결과 약 16km의 단기선에 대해 GPS의 변위 검출능력은 수평성분에서 약 2 mm, 수직성분에서 약 8 mm에 이른다는 것을 알 수 있었다. 이 결과를 토대로 구조물의 변위 측정에 대한 GPS의 활용 가능성에 대해 고찰하였다.

  • PDF

LAND COVER CLASSIFICATION BY USING SAR COHERENCE IMAGES

  • Yoon, Bo-Yeol;Kim, Youn-Soo
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
    • /
    • pp.76-79
    • /
    • 2008
  • This study presents the use of multi-temporal JERS-1 SAR images to the land cover classification. So far, land cover classified by high resolution aerial photo and field survey and so on. The study site was located in Non-san area. This study developed on multi-temporal land cover status monitoring and coherence information mapping can be processing by L band SAR image. From July, 1997 to October, 1998 JERS SAR images (9 scenes) coherence values are analyzed and then classified land cover. This technique which forms the basis of what is called SAR Interferometry or InSAR for short has also been employed in spaceborne systems. In such systems the separation of the antennas, called the baseline is obtained by utilizing a single antenna in a repeat pass

  • PDF

EXTRACTION OF LAND COVER INFORMATION BY USING SAR COHERENCE IMAGES

  • Yoon, Bo-Yeol;Kim, Youn-Soo
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
    • /
    • pp.475-478
    • /
    • 2007
  • This study presents the use of multi-temporal JERS-1 SAR images to extract the land cover information and possibility. So far, land cover information extracted by high resolution aerial photo and field survey. The study site was located in Non-san area. This study developed on multi-temporal land cover status monitoring and coherence information mapping can be processing by L band SAR image. From July, 1997 to October, 1998 JERS SAR images (9 scenes) coherence values are analyzed and then extracted land cover information factors, so on. This technique which forms the basis of what is called SAR Interferometry or InSAR for short has also been employed in spaceborne systems. In such systems the separation of the antennas, called the baseline is obtained by utilizing a single antenna in a repeat pass

  • PDF