• ETRI Journal
• /
• 제46권3호
• /
• pp.526-537
• /
• 2024

Monitoring fetal growth in utero is crucial to anomaly diagnosis. However, current computer-vision models struggle to accurately assess the key metrics (i.e., head circumference and occipitofrontal and biparietal diameters) from ultrasound images, largely owing to a lack of training data. Mitigation usually entails image augmentation (e.g., flipping, rotating, scaling, and translating). Nevertheless, the accuracy of our task remains insufficient. Hence, we offer a U-Net fetal head measurement tool that leverages a hybrid Dice and binary cross-entropy loss to compute the similarity between actual and predicted segmented regions. Ellipse-fitted two-dimensional ultrasound images acquired from the HC18 dataset are input, and their lower feature layers are reused for efficiency. During regression, a novel region of interest pooling layer extracts elliptical feature maps, and during segmentation, feature pyramids fuse field-layer data with a new scale attention method to reduce noise. Performance is measured by Dice similarity, mean pixel accuracy, and mean intersection-over-union, giving 97.90%, 99.18%, and 97.81% scores, respectively, which match or outperform the best U-Net models.

• Imaging Science in Dentistry
• /
• 제45권1호
• /
• pp.1-5
• /
• 2015

Purpose: Lateral pterygoid muscle (LPM) plays an important role in jaw movement and has been implicated in Temporomandibular disorders (TMDs). Migraine has been described as a common symptom in patients with TMDs and may be related to muscle hyperactivity. This study aimed to compare LPM volume in individuals with and without migraine, using segmentation of the LPM in magnetic resonance (MR) imaging of the TMJ. Materials and Methods: Twenty patients with migraine and 20 volunteers without migraine underwent a clinical examination of the TMJ, according to the Research Diagnostic Criteria for TMDs. MR imaging was performed and the LPM was segmented using the ITK-SNAP 1.4.1 software, which calculates the volume of each segmented structure in voxels per cubic millimeter. The chi-squared test and the Fisher's exact test were used to relate the TMD variables obtained from the MR images and clinical examinations to the presence of migraine. Logistic binary regression was used to determine the importance of each factor for predicting the presence of a migraine headache. Results: Patients with TMDs and migraine tended to have hypertrophy of the LPM (58.7%). In addition, abnormal mandibular movements (61.2%) and disc displacement (70.0%) were found to be the most common signs in patients with TMDs and migraine. Conclusion: In patients with TMDs and simultaneous migraine, the LPM tends to be hypertrophic. LPM segmentation on MR imaging may be an alternative method to study this muscle in such patients because the hypertrophic LPM is not always palpable.

• 마케팅과학연구
• /
• 제16권2호
• /
• pp.77-94
• /
• 2006

이 연구는 가격을 품질의 지표로 사용하는 상황의 가격반응함수를 도출하여 다음과 같은 연구를 수행하였다. 첫째, 다속성 선택기준의 조합을 이용하여 세분시장별로 가격을 품질의 지표로 사용하는 하위집단과 그렇지 않은 하위집단을 추출하였고, 둘째, 기존연구에서 사용된 분석단위인 제품이나 상표에서 벗어나 세분시장을 분석단위로 하여 가격이 품질의 지표로 사용되는 세분시장을 확인하였다. 이를 위해 첫째, 중국의 홈씨어터 시장을 대상으로 CBC(choice-based conjoint analysis)를 통해 얻어진 자료를 혼합회귀분석(mixture regression model)에 의해 시장 세분화하였고, 그 결과 표본전체시장 및 세개의 세분시장에서 가격을 품질의 지표로 사용하는 독특한 가격반응함수를 가진 세분시장을 확인하였다. 이를 통해 학술적으로는 가격-품질 평가집단 연구의 범위를 세분시장별로 확대하고, 실무적으로는 실무종사자는 가격-품질 평가가 이루어지는 가격대보다 높은 가격을 시장에 제시함으로써 이익을 더 많이 취할 수 있게 되는 장점을 기대하였다.

• The International Journal of Costume Culture
• /
• 제3권3호
• /
• pp.246-261
• /
• 2000

The purpose of this study was to investigate the apparel purchasing behavior of adult women consumer groups divided by materialism. The specific objects of this study were ; 1) to examine the degree of materialism, impulsive buying, and conspicuous consumption. 2) to examine the correlation between impulsive buying, materialism, and conspicuous consumption, and to examine the relative influences of impulsive buying, materialism affecting conspicuous consumption. 3) to classify groups according to the level of the propensity for materialism, and to examine the clothing purchasing behavior of the divided groups. Data were administered to 357 adult women living in Sunchol from June to July 1999. For analysis of the data, factor analysis, one-way ANOVE, duncan's multiple range test, frequency and χ²-test were employed. The results of this study were summarized as follows. 1. Materialism and impulsive buying have shown higher than middle score, and conspicuous consumption has shown similar to middle score. 2. The correlation between materialism, impulsive buying, and conspicuous consumption has shown similar to middle score. The higher the materialism and experience of impulsive buying was, the higher was the conspicuous consumption. According to the results of regression analysis examining the relative influence of variables affecting conspicuous consumption. According to the results of regression analysis examining the relative influence of variables affecting conspicuous consumption, the relative importance of the variables were in the order of ; success-symbolic materialism, life-centered materialism, happiness-pursuing materialism, in the order of ; success-symbolic materialism, life-centered materialism, happiness-pursuing materialism, impulsive buying and their explanatory power totalled 35.2%. 3. Evaluating attributes of product, the type of purchasing store, the place of purchasing, the need of high class department store, purchasing price range, and accompanying people when purchasing were the factors influencing the apparel purchasing behavior.

• 한국지역사회생활과학회지
• /
• 제20권2호
• /
• pp.145-156
• /
• 2009

The purpose of this study was to explore socio-economic factors as determinants of food behavior and self-evaluation on meeting dietary guidelines. The data were derived from the KNHANES collected in 2007. A multidimensional framework of the determinants of food behavior was used, including age, gender, region, occupation, education, income and nutritional knowledge. The determinants of food behavior and self-evaluation were estimated by ordered logistic regression models. Food behavior was measured by dietary diversity scores including six food groups, which were cereals, vegetables, meats, fruits, milk, and oils. Self-evaluation on meeting dietary guidelines was based on responses from questionnaires for implementing Korean dietary guidelines. In general, the respondents who fulfilled all criteria were few. There were some differences between dietary diversity scores and self-evaluation on meeting dietary guidelines. Age, gender, and educational level showed effect on food behavior and self-evaluation. For dietary diversity scores, the individuals who were younger male, graduated from college were more likely to consume more various foods. The individuals who were older female, graduated from high school were more likely to meet dietary guidelines. Occupation was associated only with self-evaluation. Age and gender were associated with food behavior as well as self-evaluation. Income and marital status were associated only with dietary diversity scores. Reading food label and occupation were associated only with self-evaluation. The food behavior of married individuals was less in line with the dietary diversity scores than singles. In conclusion the differences between objective measure and subjective measure on individuals' diet showed more efforts like segmented nutritional education would be needed to increase the quality of dietary life.

• Smart Structures and Systems
• /
• 제16권1호
• /
• pp.163-181
• /
• 2015

This research investigates the structural health monitoring of nonlinear structures after a major seismic event. It considers the identification of flag-shaped or pinched hysteresis behavior in response to structures as a more general case of a normal hysteresis curve without pinching. The method is based on the overall least squares methods and the log likelihood ratio test. In particular, the structural response is divided into different loading and unloading sub-half cycles. The overall least squares analysis is first implemented to obtain the minimum residual mean square estimates of structural parameters for each sub-half cycle with the number of segments assumed. The log likelihood ratio test is used to assess the likelihood of these nonlinear segments being true representations in the presence of noise and model error. The resulting regression coefficients for identified segmented regression models are finally used to obtain stiffness, yielding deformation and energy dissipation parameters. The performance of the method is illustrated using a single degree of freedom system and a suite of 20 earthquake records. RMS noise of 5%, 10%, 15% and 20% is added to the response data to assess the robustness of the identification routine. The proposed method is computationally efficient and accurate in identifying the damage parameters within 10% average of the known values even with 20% added noise. The method requires no user input and could thus be automated and performed in real-time for each sub-half cycle, with results available effectively immediately after an event as well as during an event, if required.

• Genomics & Informatics
• /
• 제19권1호
• /
• pp.11.1-11.8
• /
• 2021

For the novel coronavirus disease 2019 (COVID-19), predictive modeling, in the literature, uses broadly susceptible exposed infected recoverd (SEIR)/SIR, agent-based, curve-fitting models. Governments and legislative bodies rely on insights from prediction models to suggest new policies and to assess the effectiveness of enforced policies. Therefore, access to accurate outbreak prediction models is essential to obtain insights into the likely spread and consequences of infectious diseases. The objective of this study is to predict the future COVID-19 situation of Korea. Here, we employed 5 models for this analysis; SEIR, local linear regression (LLR), negative binomial (NB) regression, segment Poisson, deep-learning based long short-term memory models (LSTM) and tree based gradient boosting machine (GBM). After prediction, model performance comparison was evelauated using relative mean squared errors (RMSE) for two sets of train (January 20, 2020-December 31, 2020 and January 20, 2020-January 31, 2021) and testing data (January 1, 2021-February 28, 2021 and February 1, 2021-February 28, 2021) . Except for segmented Poisson model, the other models predicted a decline in the daily confirmed cases in the country for the coming future. RMSE values' comparison showed that LLR, GBM, SEIR, NB, and LSTM respectively, performed well in the forecasting of the pandemic situation of the country. A good understanding of the epidemic dynamics would greatly enhance the control and prevention of COVID-19 and other infectious diseases. Therefore, with increasing daily confirmed cases since this year, these results could help in the pandemic response by informing decisions about planning, resource allocation, and decision concerning social distancing policies.

• Korean Journal of Radiology
• /
• 제22권7호
• /
• pp.1021-1033
• /
• 2021

Objective: To assess the expression of vascular normalization genes in different molecular subtypes of breast cancer and to determine whether molecular subtypes with a higher vascular normalization gene expression can be identified using dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) and intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI). Materials and Methods: This prospective study evaluated 306 female (mean age ± standard deviation, 50 ± 10 years), recruited between January 2014 and August 2017, who had de novo breast cancer larger than 1 cm in diameter (308 tumors). DCE MRI followed by IVIM DWI studies using 11 different b-values (0 to 1200 s/mm²) were performed on a 1.5T MRI system. The Tofts model and segmented biexponential IVIM analysis were used. For each tumor, the molecular subtype (according to six [I-VI] subtypes and PAM50 subtypes), expression profile of genes for vascular normalization, pericytes, and normal vascular signatures were determined using freshly frozen tissue. Statistical associations between imaging parameters and molecular subtypes were examined using logistic regression or linear regression with a significance level of p = 0.05. Results: Breast cancer subtypes III and VI and PAM50 subtypes luminal A and normal-like exhibited a higher expression of genes for vascular normalization, pericyte markers, and normal vessel function signature (p < 0.001 for all) compared to other subtypes. Subtypes III and VI and PAM50 subtypes luminal A and normal-like, versus the remaining subtypes, showed significant associations with K^trans, k_ep, v_p, and IAUGC_BN90 on DEC MRI, with relatively smaller values in the former. The subtype grouping was significantly associated with D, with relatively less restricted diffusion in subtypes III and VI and PAM50 subtypes luminal A and normal-like. Conclusion: DCE MRI and IVIM parameters may identify molecular subtypes of breast cancers with a different vascular normalization gene expression.

• 한국생활과학회지
• /
• 제22권4호
• /
• pp.677-691
• /
• 2013

The purpose of this study was to examine the influence of make-up attitude and body-related value on clothing behavior. The subjects were 315 female college students in Gyeongsang provinces. The obtained data were analyzed by reliability analysis, factor analysis, cluster analysis, one-way ANOVA, Duncan's multiple range test, correlation analysis, multiple regression analysis and t-test. The major results of this study were as follows: First, four factors of make-up attitude were identified: pursuit of confidence, sociality, self-satisfaction, and positive image. Second, the subjects were categorized into three different types of groups according to make-up attitude and body-related value, respectively: high involvement type, low involvement type, and middle involvement type. Third, there was significant difference among three groups which were segmented by each make-up attitude and body-related value on clothing behaviors (sexual attractiveness, showing off, body-enhancement). Fourth, a significant positive correlation was found among four factors of make-up attitude and body operatability with clothing behaviors. Fifth, the important variables that affected the clothing behaviors were pursuit of confidence, self-satisfaction, and positive image of make-up attitude. Sixth, body-inclination significantly influenced sexual attractiveness of clothing behavior, whereas body-related value, unlike make-up attitude, only had marginal influence.

• 로봇학회논문지
• /
• 제11권1호
• /
• pp.1-8
• /
• 2016

In this paper, we propose a new algorithm of the guidance line extraction for autonomous agricultural robot based on vision camera in paddy field. It is the important process for guidance line extraction which finds the central point or area of rice row. We are trying to use the central region data of crop that the direction of rice leaves have convergence to central area of rice row in order to improve accuracy of the guidance line. The guidance line is extracted from the intersection points of extended virtual lines using the modified robust regression. The extended virtual lines are represented as the extended line from each segmented straight line created on the edges of the rice plants in the image using the Hough transform. We also have verified an accuracy of the proposed algorithm by experiments in the real wet paddy.