• Title/Summary/Keyword: exact approach

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A Realtime Expression Control for Realistic 3D Facial Animation (현실감 있는 3차원 얼굴 애니메이션을 위한 실시간 표정 제어)

  • Kim Jung-Gi;Min Kyong-Pil;Chun Jun-Chul;Choi Yong-Gil
    • Journal of Internet Computing and Services
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    • v.7 no.2
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    • pp.23-35
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    • 2006
  • This work presents o novel method which extract facial region und features from motion picture automatically and controls the 3D facial expression in real time. To txtract facial region and facial feature points from each color frame of motion pictures a new nonparametric skin color model is proposed rather than using parametric skin color model. Conventionally used parametric skin color models, which presents facial distribution as gaussian-type, have lack of robustness for varying lighting conditions. Thus it needs additional work to extract exact facial region from face images. To resolve the limitation of current skin color model, we exploit the Hue-Tint chrominance components and represent the skin chrominance distribution as a linear function, which can reduce error for detecting facial region. Moreover, the minimal facial feature positions detected by the proposed skin model are adjusted by using edge information of the detected facial region along with the proportions of the face. To produce the realistic facial expression, we adopt Water's linear muscle model and apply the extended version of Water's muscles to variation of the facial features of the 3D face. The experiments show that the proposed approach efficiently detects facial feature points and naturally controls the facial expression of the 3D face model.

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Modified Empirical Formula of Dynamic Amplification Factor for Wind Turbine Installation Vessel (해상풍력발전기 설치선박의 수정 동적증폭계수 추정식)

  • Ma, Kuk-Yeol;Park, Joo-Shin;Lee, Dong-Hun;Seo, Jung-Kwan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.6
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    • pp.846-855
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    • 2021
  • Eco-friendly and renewable energy sources are actively being researched in recent times, and of shore wind power generation requires advanced design technologies in terms of increasing the capacities of wind turbines and enlarging wind turbine installation vessels (WTIVs). The WTIV ensures that the hull is situated at a height that is not affected by waves. The most important part of the WTIV is the leg structure, which must respond dynamically according to the wave, current, and wind loads. In particular, the wave load is composed of irregular waves, and it is important to know the exact dynamic response. The dynamic response analysis uses a single degree of freedom (SDOF) method, which is a simplified approach, but it is limited owing to the consideration of random waves. Therefore, in industrial practice, the time-domain analysis of random waves is based on the multi degree of freedom (MDOF) method. Although the MDOF method provides high-precision results, its data convergence is sensitive and difficult to apply owing to design complexity. Therefore, a dynamic amplification factor (DAF) estimation formula is developed in this study to express the dynamic response characteristics of random waves through time-domain analysis based on different variables. It is confirmed that the calculation time can be shortened and accuracy enhanced compared to existing MDOF methods. The developed formula will be used in the initial design of WTIVs and similar structures.

Analysis of Spatial Characteristics of Vacant Houses using Geographic Weighted Regression Model - Focus on Busan Metropolitan City - (지리가중회귀모델을 적용한 빈집 발생의 공간적 특성 분석 - 부산광역시를 대상으로 -)

  • KIM, Ji-Yun;KIM, Ho-Yong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.24 no.1
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    • pp.68-79
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    • 2021
  • The recent occurrence of vacant houses in urban areas is a remarkable social problem. One of the physical declines, the occurrence of vacant houses, accelerates various social and economic declines, such as a decline in population and a slump in the commercial district. Vacant houses have regional characteristics and spatial influence, and it is necessary to approach them locally in order to grasp the exact status of vacant houses. Therefore, in this study, the effect of urban decline on the occurrence of vacant homes was examined by region using global Moran's I and Geographic Weighted Regression(GWR) model. As a result of the analysis, there were spatial autocorrelation and heterogeneity in the occurrence of vacant houses in each eup·myeon·dong, Busan metropolitan city. In addition, there is a difference in the influence of each variable of urban decline on the occurrence of vacant houses, and even the same variable of urban decline has different effects on the occurrence of vacant houses in different regions. Therefore, it is expected that a more efficient vacant home management plan can be presented if the GWR model is used to analyze the coefficient values differentiated by region and categorize the occurrence of vacant houses.

An Efficient Wireless Signal Classification Based on Data Augmentation (데이터 증강 기반 효율적인 무선 신호 분류 연구 )

  • Sangsoon Lim
    • Journal of Platform Technology
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    • v.10 no.4
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    • pp.47-55
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    • 2022
  • Recently, diverse devices using different wireless technologies are gradually increasing in the IoT environment. In particular, it is essential to design an efficient feature extraction approach and detect the exact types of radio signals in order to accurately identify various radio signal modulation techniques. However, it is difficult to gather labeled wireless signal in a real environment due to the complexity of the process. In addition, various learning techniques based on deep learning have been proposed for wireless signal classification. In the case of deep learning, if the training dataset is not enough, it frequently meets the overfitting problem, which causes performance degradation of wireless signal classification techniques using deep learning models. In this paper, we propose a generative adversarial network(GAN) based on data augmentation techniques to improve classification performance when various wireless signals exist. When there are various types of wireless signals to be classified, if the amount of data representing a specific radio signal is small or unbalanced, the proposed solution is used to increase the amount of data related to the required wireless signal. In order to verify the validity of the proposed data augmentation algorithm, we generated the additional data for the specific wireless signal and implemented a CNN and LSTM-based wireless signal classifier based on the result of balancing. The experimental results show that the classification accuracy of the proposed solution is higher than when the data is unbalanced.

Continuous Time Markov Process Model for Nuclide Decay Chain Transport in the Fractured Rock Medium (균열 암반 매질에서의 핵종의 붕괴사슬 이동을 위한 연속시간 마코프 프로세스 모델)

  • Lee, Y.M.;Kang, C.H.;Hahn, P.S.;Park, H.H.;Lee, K.J.
    • Nuclear Engineering and Technology
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    • v.25 no.4
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    • pp.539-547
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    • 1993
  • A stochastic approach using continuous time Markov process is presented to model the one-dimensional nuclide transport in fractured rock media as a further extension for previous works[1-3]. Nuclide transport of decay chain of arbitrary length in the single planar fractured rock media in the vicinity of the radioactive waste repository is modeled using a continuous time Markov process. While most of analytical solutions for nuclide transport of decay chain deal with the limited length of decay chain, do not consider the case of having rock matrix diffusion, and have very complicated solution form, the present model offers rather a simplified solution in the form of expectance and its variance resulted from a stochastic modeling. As another deterministic way, even numerical models of decay chain transport, in most cases, show very complicated procedure to get the solution and large discrepancy for the exact solution as opposed to the stochastic model developed in this study. To demonstrate the use of the present model and to verify the model by comparing with the deterministic model, a specific illustration was made for the transport of a chain of three member in single fractured rock medium with constant groundwater flow rate in the fracture, which ignores the rock matrix diffusion and shows good capability to model the fractured media around the repository.

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Scoring System to Predict Malignancy for MRI-Detected Lesions in Breast Cancer Patients: Diagnostic Performance and Effect on Second-Look Ultrasonography (유방암 환자의 MRI에서 발견된 병변의 악성 예측을 위한 점수체계: 진단적 능력과 이차 초음파 결정에 미치는 영향)

  • Young Geol Kwon;Ah Young Park
    • Journal of the Korean Society of Radiology
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    • v.81 no.2
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    • pp.379-394
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    • 2020
  • Purpose To design a scoring system to predict malignancy of additional MRI-detected lesions in breast cancer patients. Materials and Methods Eighty-six lesions (64 benign and 22 malignant) detected on preoperative MRI of 68 breast cancer patients were retrospectively included. The clinico-radiologic features were correlated with the histopathologic results using the Student's t-test, Fisher's exact test, and logistic regression analysis. The scoring system was designed based on the significant predictive features of malignancy, and its diagnostic performance was compared with that of the Breast Imaging-Reporting and Data System (BI-RADS) category. Results Lesion size ≥ 8 mm (p < 0.001), location in the same quadrant as the primary cancer (p = 0.005), delayed plateau kinetics (p = 0.010), T2 isointense (p = 0.034) and hypointense (p = 0.024) signals, and irregular mass shape (p = 0.028) were associated with malignancy. In comparison with the BI-RADS category, the scoring system based on these features with suspicious non-mass internal enhancement increased the diagnostic performance (area under the receiver operating characteristic curve: 0.918 vs. 0.727) and detected three false-negative cases. With this scoring system, 22 second-look ultrasound examinations (22/66, 33.3%) could have been avoided. Conclusion The scoring system based on the lesion size, location relative to the primary cancer, delayed kinetic features, T2 signal intensity, mass shape, and non-mass internal enhancement can provide a more accurate approach to evaluate MRI-detected lesions in breast cancer patients.

An Exploratory Study of the Determinants of Global Sourcing Intention in Korean Clothing Sewing Industry: Focusing on Women's Knit Wear Production (국내 의류봉제 산업의 글로벌소싱 의향 고려요인 연구: 여성니트복종(women's knit wear) 생산을 중심으로)

  • Dabin Yoo;Sunwook Chung
    • Asia-Pacific Journal of Business
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    • v.14 no.4
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    • pp.67-85
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    • 2023
  • Purpose - This study seeks to investigate the determinants of global sourcing intention in clothing sewing industry, in particular with its focus on women's knit wear production. Design/methodology/approach - This study collected a unique set of qualitative data through 31 in-depth interviews with fashion brands, promotion agencies, and sewing factories between July 2023 and October 2023. In addition, it analyzed the dataset using the MAXQDA to complement the research findings. Findings - We have two findings. First, the interviewees commonly mentioned the following factors as reasons for considering global sourcing: the human factors(aging of skilled technicians and labor shortages), the financial factors(gap in production unit prices at home and abroad), the relational factors(lack of novelty), and the physical factors(loss of production infrastructure and network), while the human factors(skilled workforce), the production factors(delivery date and product quality), and the relational factors(timely communication and mutual trust) as reasons for continuing domestic sourcing. Additional code analysis of interview also supports this finding. On the other hand, there was also a subtle difference between buyers(brands) and suppliers(promotion agencies and processing plants), and buyers consider the exact delivery date critical so that they could see trend-sensitive women's knit wear on time, and suppliers took production costs, labor costs, and labor shortages, which are financial factors, more seriously. Research implications or Originality - This study provides a richer and more balanced view of existing literature, which has generally tended to introduce global sourcing across the clothing industry despite the existence of various diversity within the industry. In addition, through qualitative research, we introduce that the sewing industry is carried out according to complex factors, and by revealing and categorizing the determinants of global sourcing, we supplement the existing research on the clothing sewing industry centered on survey. On a practical note, this study introduces that there is a difference in view of domestic sourcing and global sourcing between buyers(brands) and suppliers(promotion agencies and sewing factories), suggesting practical implications for revitalizing networks and deriving win-win cooperation network models among members in the future.

Validating a New Approach to Quantify Posterior Corneal Curvature in Vivo (각막 후면 지형 측정을 위한 새로운 방법의 신뢰도 분석 및 평가)

  • Yoon, Jeong Ho;Avudainayagam, Kodikullam;Avudainayagam, Chitralekha;Swarbrick, Helen A.
    • Journal of Korean Ophthalmic Optics Society
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    • v.17 no.2
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    • pp.223-232
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    • 2012
  • Purpose: Validating a new research method to determine posterior corneal curvature and asphericity(Q) in vivo, based on measurements of anterior corneal topography and corneal thickness. Methods: Anterior corneal topographic data, derived from the Medmont E300 corneal topographer, and total corneal thickness data measured along the horizontal corneal meridian using the Holden-Payor optical pachometer, were used to calculate the anterior and posterior corneal apical radii of curvature and Q. To calculate accurate total corneal thickness the local radius of anterior corneal curvature, and an exact solution for the relationship between real and apparent thickness were taken into consideration. This method differs from previous approach. An elliptical curve for anterior and posterior cornea were calculated by using best fit algorism of the anterior corneal topographic data and derived coordinates of the posterior cornea respectively. For validation of the calculations of the posterior corneal topography, ten polymethyl methacrylate (PMMA) lenses and right eyes of five adult subjects were examined. Results: The mean absolute accuracy (${\pm}$standard deviation(SD)) of calculated posterior apical radius and Q of ten PMMA lenses was $0.053{\pm}0.044mm$ (95% confidence interval (CI) -0.033 to 0.139), and $0.10{\pm}0.10$ (95% CI -0.10 to 0.31) respectively. The mean absolute repeatability coefficient (${\pm}SD$) of the calculated posterior apical radius and Q of five human eyes was $0.07{\pm}0.06mm$ (95% CI -0.05 to 0.19) and $0.09{\pm}0.07$ (95% CI -0.05 to 0.23), respectively. Conclusions: The result shows that acceptable accuracy in calculations of posterior apical radius and Q was achieved. This new method shows promise for application to the living human cornea.

Research on effect that market directivity gets in real estate transaction result (시장지향성이 부동산거래 성과에 미치는 영향 : 부동산 중개업소 중심으로)

  • Lee, Sang-Gyu;Kim, Seok-Gon;Hwang, Hwa-Cheol
    • The Journal of Industrial Distribution & Business
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    • v.1 no.1
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    • pp.23-31
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    • 2010
  • In this study, market orientation affects the real estate transaction and about the various parameters examined, the real estate transactions, market orientation and intensity of competition in the market upheaval and the impact was seen on the results can be summarized as follows. First, market orientation and about the relationship between real estate transactions were examined. Each variable of customer satisfaction information generation, information dissemination, information was used for the reaction. Among them, the dissemination of information, information about the reaction produces a lot better the customer satisfaction was the result. In other words, the dissemination of information and availability of information to real estate transactions, the more you can improve customer satisfaction. While the information does not appear to be generated as a result of the impact of market orientation when the first phase of the creation of market information and the customer's needs and preferences of current and future information and external factors affecting them to gather information about It is difficult to assess realistically can be seen. This is both our customers and dealers in real estate purchase or trade items for the exact targets, but the general approach the start of trading because by necessity. Therefore, a clear standard for real estate deals in and nine minutes to all sellers of real estate purchases through a process of communication to enable effective approach should be. Second, market orientation and about the relationship between real estate transactions were examined. The information for each variable in re-creating transactions, information dissemination, information was used for the reaction. Variable affects all the information creation, dissemination of information, information about the reaction the better the deal re-done show that two can be frequent. In other words, information generation, information dissemination and utilization of information to real estate transactions, the more customers the added responsibilities of the re-trade can be seen. Third, the relationship between market orientation and in the real estate market upheaval of environmental factors on the relationship between gender were examined. Each variable of customer satisfaction information generation, information dissemination, information was used for the reaction. Among them, the dissemination of information, information about the reaction produces a lot better the customer satisfaction was the result. In other words, the dissemination of information, depending on the market upheaval and the availability of information to raise the real estate can increase customer satisfaction. Fourth, market orientation and environmental factors in the relationship between real estate transactions and about the relationship between competition intensity was investigated. The information for each variable in re-creating transactions, information dissemination, information was used for the reaction. Variable affects all the information creation, dissemination of information, information about the reaction the better the deal re-done show that two can be frequent. In other words, information generation, information dissemination and utilization of information and the higher intensity of competition or unyounghameusseo ttaemaewoo active real estate transactions to provide our customers the added responsibilities of the re-trade can be seen. If more comprehensive, market orientation, according to real estate transactions and environmental factors affecting the performance was also different. Abundance of information about the current real estate it is true that the accuracy and reliability, and real estate, and are unsure about the expected benefits. So you want to trade to provide accurate information to customers and markets change rapidly and competition is severe, with more information if you have reliable information to the customer must supply can increase trading performance. Guarantee of future customer transactions and can provide valuable information and research needs to be differentiated based on the provision of real estate information should be done to achieve profitability will be a cow brokerage.

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CONSIDERATIONS OF ANESTHETIC METHOD OF DEEP IMPACTED MESIODENS (심부 매복 정중 과잉치 수술 시 마취방법 선택)

  • Min, Soo-Young;Song, Je-Seon;Lee, Jae-Ho;Choi, Hyung-Jun;Son, Heung-Kyu;Kim, Seong-Oh
    • Journal of the korean academy of Pediatric Dentistry
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    • v.39 no.1
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    • pp.90-96
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    • 2012
  • Supernumerary tooth occurs most frequently at premaxilla area. Followed by mandibular premolar area, mandibular fourth molar area, maxillary paramolar area. Mesiodens are mainly impacted in the palatal area and surgical approach is made at palatal side. The time of surgery remains controversial. In case of inverted or horizontal impacted supernumerary tooth, intraosseous tooth movement and vertical growth of premaxilla makes surgical extraction more difficult. And also the more quantity of removed bone is, the higher degree of difficulty is. Inverted mesiodens of these cases were impacted superior to apex level of adjacent permanent incisor. Although CT examination revealed exact location of impacted tooth, surgical procedure including ostectomy may take a long time more than expected. So, before surgical extraction, it's need to be considered several factors such as necessity of CT taking, degree of difficulty, direction of surgical approach, necessity of general anesthesia etc.