• Title/Summary/Keyword: Two stage approach

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Feature Variance and Adaptive classifier for Efficient Face Recognition (효과적인 얼굴 인식을 위한 특징 분포 및 적응적 인식기)

  • Dawadi, Pankaj Raj;Nam, Mi Young;Rhee, Phill Kyu
    • Proceedings of the Korea Information Processing Society Conference
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    • 2007.11a
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    • pp.34-37
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    • 2007
  • Face recognition is still a challenging problem in pattern recognition field which is affected by different factors such as facial expression, illumination, pose etc. The facial feature such as eyes, nose, and mouth constitute a complete face. Mouth feature of face is under the undesirable effect of facial expression as many factors contribute the low performance. We proposed a new approach for face recognition under facial expression applying two cascaded classifiers to improve recognition rate. All facial expression images are treated by general purpose classifier at first stage. All rejected images (applying threshold) are used for adaptation using GA for improvement in recognition rate. We apply Gabor Wavelet as a general classifier and Gabor wavelet with Genetic Algorithm for adaptation under expression variance to solve this issue. We have designed, implemented and demonstrated our proposed approach addressing this issue. FERET face image dataset have been chosen for training and testing and we have achieved a very good success.

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Keypoint-based Deep Learning Approach for Building Footprint Extraction Using Aerial Images

  • Jeong, Doyoung;Kim, Yongil
    • Korean Journal of Remote Sensing
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    • v.37 no.1
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    • pp.111-122
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    • 2021
  • Building footprint extraction is an active topic in the domain of remote sensing, since buildings are a fundamental unit of urban areas. Deep convolutional neural networks successfully perform footprint extraction from optical satellite images. However, semantic segmentation produces coarse results in the output, such as blurred and rounded boundaries, which are caused by the use of convolutional layers with large receptive fields and pooling layers. The objective of this study is to generate visually enhanced building objects by directly extracting the vertices of individual buildings by combining instance segmentation and keypoint detection. The target keypoints in building extraction are defined as points of interest based on the local image gradient direction, that is, the vertices of a building polygon. The proposed framework follows a two-stage, top-down approach that is divided into object detection and keypoint estimation. Keypoints between instances are distinguished by merging the rough segmentation masks and the local features of regions of interest. A building polygon is created by grouping the predicted keypoints through a simple geometric method. Our model achieved an F1-score of 0.650 with an mIoU of 62.6 for building footprint extraction using the OpenCitesAI dataset. The results demonstrated that the proposed framework using keypoint estimation exhibited better segmentation performance when compared with Mask R-CNN in terms of both qualitative and quantitative results.

Extracorporeal Pedicles for Free Flap Reconstruction in Diabetic Lower Extremity Wounds

  • Alejandro R. Gimenez;Daniel Lazo;Salomao Chade;Alex Fioravanti;Olimpio Colicchio;Daniel Alvarez;Ernani Junior;Sarth Raj;Amjed Abu-Ghname;Marco Maricevich
    • Archives of Plastic Surgery
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    • v.49 no.6
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    • pp.782-784
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    • 2022
  • Diabetic foot ulcers are a severe complication of diabetes, and their management requires a multidisciplinary approach for optimal management. When treating these ulcers, limb salvage remains the ultimate goal. In this article, we present the "hanging" free flap for the reconstruction of chronic lower extremity diabetic ulcers. This two-staged approach involves standard free flap harvest and inset; however, following inset the "hanging" pedicle is covered within a skin graft instead of making extraneous incisions within the undisturbed soft tissues or tunnels that can compress the vessels. After incorporation, a second-stage surgery is performed in 4 to 6 weeks which entails pedicle division, flap inset revision, and end-to-end reconstruction of the recipient vessel. Besides decreasing the number of incisions on diabetic patients, our novel technique utilizing the "hanging" pedicle simplifies flap monitoring and inset and allows reconstruction of recipient vessels to reestablish distal blood flow.

Improvement of Face Recognition Rate by Normalization of Facial Expression (표정 정규화를 통한 얼굴 인식율 개선)

  • Kim, Jin-Ok
    • The KIPS Transactions:PartB
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    • v.15B no.5
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    • pp.477-486
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    • 2008
  • Facial expression, which changes face geometry, usually has an adverse effect on the performance of a face recognition system. To improve the face recognition rate, we propose a normalization method of facial expression to diminish the difference of facial expression between probe and gallery faces. Two approaches are used to facial expression modeling and normalization from single still images using a generic facial muscle model without the need of large image databases. The first approach estimates the geometry parameters of linear muscle models to obtain a biologically inspired model of the facial expression which may be changed intuitively afterwards. The second approach uses RBF(Radial Basis Function) based interpolation and warping to normalize the facial muscle model as unexpressed face according to the given expression. As a preprocessing stage for face recognition, these approach could achieve significantly higher recognition rates than in the un-normalized case based on the eigenface approach, local binary patterns and a grey-scale correlation measure.

Optimization of Dose Distribution for LINAC-based Radiosurgery with Multiple Isocenters (LINAC 뇌정위적 방사선 수술시 Multiple Isocenters를 이용한 최적 선량분포 계획)

  • Suh Tae-Suk;Yoon Sei Chul;Shinn Kyung Sub;Bahk Yong Whee
    • Radiation Oncology Journal
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    • v.9 no.2
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    • pp.351-359
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    • 1991
  • The current LINAC technique for radiosurgery utilizes a single isocenter approach with multiple noncoplanar arcs. This approach results in spherical dose distributions in the target. Many arteriovenous malformations and tumors suitable for radiosurgical treatment have non-spherical or irregular shapes. The basic approach presented in this paper is to use two or multiple isocenters with standard arcs to shape irregular target volumes through the use of multiple spherical targets. Selection of reasonable irradiation parameters in the first stage is critical to the success of real-time optimization. A useful guideline for optimum isocenter separation and collimator size is developed to shape the target margin uniformly with an desired isodose surface for an elongated target. The implementation of multiple isocenters with three dimensional dose model and application of multiple isocenters approach to several cases are discussed.

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CAD System of New Concept to Support Top-Down Approach in Design (하향식 설계방식을 지원하는 새로운 개념의 CAD 시스템)

  • 김성환;이건우
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.7
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    • pp.1604-1618
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    • 1995
  • In the process of mechanical assembly design, assembly modeling systems have been used mainly for the design verification before manufacturing by enabling to check the interference and/ or the dynamic and kinematic performance. However, the conventional assembly modeling systems have a shortcoming that they can not be used in the initial design stage but can be used only after the design is fully completed. In other words conventional assembly modeling systems provide bottom-up modeling which means that the detailed modeling of components must precede the definition of relationships between them. To resolve this problem, an assembly modeling system is proposed to provide a top-down modeling environment in which components and assembly can be modeled simultaneously. To this end, an assembly data structure suitable for top-down assembly modeling has been established. Feature positioning Module(FPM) using geometric constraints has been also developed. The Sekective Solving Method proposed for FPM is based on the priority between the constraint equations and enables the designer's intent expressed by geometric constraints to be maintained throughout the whole modeling process. Finally, the feature based modeling technique using two-level features has been developed. Two-level features include an abstract model and a detailed model in a merged form in non-manifold data frame.

Clinical Application of the Delayed Procedure in the Distally Based Sural Flap (원위기저비복피판에서 지연처치의 임상적 적용)

  • Yim, Hyung-Woo;Park, Yong-Joon
    • Archives of Plastic Surgery
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    • v.37 no.6
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    • pp.775-778
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    • 2010
  • Purpose: Reconstruction of soft tissue defects with osteomyelitis in the lower third of the leg represents a challenge to plastic surgeons. Moreover, it is more arduous in multimorbid patients. One excellent option for reconstruction of these defects is to use a delayed distally based sural flap. Methods: We successfully used delayed distally based sural flap with a two-step procedure. During the first operation, radical debridement and elevation of flap were performed. The raised flap was fixed again at the donor site. The delay period ranged from seven to ten days. Between August 2008 and July 2009, we underwent operations for five patients using this technique. The size of flap varied from $10{\times}6\;cm$ to $12{\times}14\;cm$. Results: All flaps successfully survived. Partial skin loss of the grafted site was seen in two patients but no further surgical procedure was required for wound healing. Complaints of hypoesthesia on the lateral part of the foot was observed. In a three month follow-up period, hypoesthesia was resolved spontaneously. Conclusion: Delayed procedure improves the viability of distally based sural flap in high risk, critically multimorbid patients. We recommend that, if a two-stage operative approach is required, the delayed procedure should be considered.

Cost Prediction Models in the Early Stage of the Roadway Planning and Designbased on Limited Available Information (가용정보를 활용한 기획 및 설계초기 단계의 도로 공사비 예측모델)

  • Kwak, Soo-Nam;Kim, Du-Yon;Kim, Byoung-Il;Choi, Seok-Jin;Han, Seung-Heon
    • Korean Journal of Construction Engineering and Management
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    • v.10 no.4
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    • pp.87-100
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    • 2009
  • The quality of early cost estimates is critical to the feasibility analysis and budget allocation decisions for public capital projects. Various researches have been attempted to develop cost prediction models in the early stage of a construction project. However, existing studies are limited on its applicability to actual projects because they focus primarily on a specific phase as well as utilize restricted information while the amount of information collectable differs from one another along with the project stages. This research aims to develop two-staged cost estimation model for the schematic planning and preliminary design process of a construction projects, considering the available information of each phase. In the schematic planning stage where outlined information of a project is only available, the Case-Based Reasoning model is used for easy and rapid elicitation of a project cost based on the extensive database of more than 90 actual highway construction projects. Then, the representing quantity-based model is proposed for the preliminary design stage where more information on the quantities and unit costs are collectable based on the alternative routes and cross-sections of a highway project. Real case studies are used to demonstrate and validate the benefits of the proposed approach. Through the two-stage cost estimation system, users are able to hold a timely prospect to presume the final cost within the budge such that feasibility study as well as budget allocation decisions are made on effectively and competitively.

An Approach of the Eastern-Western Nursing Sciences for the Management of Hypertensive Patients (고혈압환자관리를 위한 동서간호학적 접근)

  • Kim, Kwuy-Boon;Kim, Ce-Ran;Chae, Jeong-Sook
    • Journal of East-West Nursing Research
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    • v.3 no.1
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    • pp.27-38
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    • 1998
  • This study was carried out to understand the general conditions about management of hypertension and the differences in opinions between the Eastern-Western Nursing Sciences. In this context, this study was aimed to find out a possible integration of the Eastern-Western Nursing Sciences for the management of hypertension and to suggest a distinct frame of Korean nursing intervention method which is unique for the hypertensive patients by combining two hypertensive management systems originated from the Western type, "mainly classified by stage", and the Eastern type, "typically classified by form" as they are identified in the literature. From the research literature including both domestic and foreign, this study identified that exuberance of Yang of the Liver form mainly appeared to the patient who is at a border hypertension or the first stage of hypertension, Deficiency of Yin of the Liver and Kidneys form mostly appeared to the first stage and the second stage of Hypertension and Deficiency of the both of Yin and Yang form appeared to the third stage of Hypertension. These unifications of the types of Hypertension classified by stages and forms suggest the possibility not only of integration of the Eastern-western Medicine but also of establishment for the intervention of specific nursing management which is the united Eastern-western Nursing Science for the Hypertension. Hence, the new frame for the nursing management of Hypertensive patient is suggested as follows : 1) In case of the exuberance of Yang of the Liver form, as classified by form which is categorized to the border Hypertension or the first stage of Hypertension, nursing intervention should include general therapy, cooking meal and neutral care to restrain the condition of the exuberance of Yang of the liver. 2) In case of the deficiency of Yin of the liver and the Kidneys form, as classified by form which is categorized to the second stage of Hypertension, nursing intervention should include both the general and drug therapy and their use in combination with cooking meal and neural care to restrain the condition of the deficiency of Yin of the Li ver and Kidneys. 3) In case of the deficiency of both of Yin and Yang form, as classified by form which is categorized to he third stage of Hypertension should include both the general therapy and drug therapy and their use in combination with cooking meal and neural care to restrain the condition of deficiency of the both of Yin and Yang. In addition, using this basic frame of Hypertensive management, a specific way of nursing intervention, which is suitable for exuberance of Yang of the Liver form, deficiency of Yin of the Liver and Kidneys form, and deficiency of both of the Yin and Yang form and classified by Korean herbal medicine related to hypertension, should be pursued continuously in the future.

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Analysis of News Articles Regarding Safety Issue of HPV Vaccine (자궁경부암 백신 안전성 관련 언론보도 분석)

  • Lee, Mina;Hong, Juhyun
    • Journal of Internet Computing and Services
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    • v.19 no.2
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    • pp.77-88
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    • 2018
  • In order to prevent cervical cancer, free vaccination against cervical cancer(HPV vaccine) for 12-year-old girls has been ongoing since June 2016. The purpose of this study is to investigate how the media reported the risk information of HPV vaccine side effects and to suggest implications for government's risk communication and policy PR. The time frame was divided into two stages, stage 1(policy formation stage, 6 months before the start of free HPV vaccination) and stage 2(policy execution stage, 6 months after the free HPV vaccination was implemented). A total of 314 news articles on HPV vaccine safety and HPV Vaccine side effects were analyzed by content analysis and network analysis. The number of articles increased at stage 2 and the Centers for Disease Control and Prevention emphasized the safety of HPV vaccine and encouraged the inoculation while highlighting the effectiveness of the vaccine. Regarding HPV vaccine side effects, cases against vaccination in Japan were mainly reported at stage 1, whereas cases of HPV vaccine side effects from other countries such as Europe and USA were frequently reported at stage 2. In order to increase vaccination rate of HPV vaccine, it is time to take a strategic approach to prevent vague fear or anxiety about the vaccine.