Creating First-Mover Advantages: The Case of Samsung Electronics

This paper analyzes the sources of first-mover advantages by examining the case of Samsung Electronics, a firm which has maintained and strengthened the technological leadership in the DRAM industry since 1992. The focus is on endogeneity of first-mover advantages under changing technological and competitive environments, part of which are also shaped by the technology leader. The paper also discusses general implications of this case study for strategy and organization for innovation.First-mover advantages, innovation, firm growth, Samsung Electronics, semiconductors

Paramagnetic state in d-wave Superconductors

We study theoretically the paramagnetic state in d-wave superconductors. We present the specific heat, the magnetization, superfluid density obtained within the weak-coupling model. At low temperatures and for small magnetic fields they exhibit simple power law behaviors, which should be accessible experimentally in hole-doped high-T_c cuprates and \kappa-(ET)_2 salts in a magnetic field within the conducting plane.Comment: 5 pages(EuroTeX), 13 figures, submitted to Europhysics Letter

품질 관리 및 분류 성능 향상을 위한 흉부 방사선 이미지 검사 네트워크

학위논문(석사) -- 서울대학교대학원 : 데이터사이언스대학원 데이터사이언스학과, 2022.2. 이승근.Predicting the presence of diseases in chest radiographs using deep learning methods is one of the most common medical imaging tasks. Recently, the performances of the state-of-the-art models outperformed the radiologists for some diseases. However, there are still many chest radiographs that even those state-of-the-art models cannot correctly classify. Some chest radiographs are either too difficult to classify or contain elements that are confusing to the models. This paper proposes a chest radiograph inspection network (CRI-Net), a deep learning method that quantifies how well or poorly a disease classification model will classify chest radiographs. Large dataset experiments showed that the method can perform quality control on chest radiographs and further can enhance the AUROC of the disease classification predictions for some diseases.딥러닝 방법론을 사용해 흉부 방사선 사진에서 질병의 존재를 예측하는 것은 가장 일반적인 의료 영상 작업 중 하나다. 최신 모델들은 일부 질병 분류에 대해 방사선 전문의를 능가할 정도로 발전했다. 그러나 이러한 모델로도 정확하게 분류할 수 없는 흉부 방사선 사진은 여전히 많다. 일부 흉부 방사선 사진은 분류하기에 너무 어렵거나 모델에게 혼동을 주는 요소를 갖고 있다. 본 논문은 질병 분류 모델이 흉부 방사선 사진을 얼마나 잘, 혹은 잘못 분류할지를 정량화하는 딥러닝 방법론인 흉부 방사선 사진 검사 네트워크(CRI-Net)를 제안한다. 대용량 데이터로 실험한 결과, 해당 방법론이 일부 질병에 대해 흉부 방사선 사진에 대한 품질 관리를 수행할 수 있고 질병 분류 예측 AUROC를 강화할 수 있음을 확인했다.Abstract i Contents ii List of Figures iv List of Tables v 1 Introduction 1 2 Related Works 3 3 Methods 5 3.1 Data 5 3.2 Disease Classification Model 5 3.3 Cross-Validation 7 3.4 DifficultyLabeling 7 3.5 CRI-Net 10 4 Experiments 12 4.1 Setup 12 4.2 Quality Control 12 4.3 AUROC Performance Boosting 13 5 Results 16 5.1 Quality Control 16 5.2 AUROC Performance Boosting 18 6 Discussion 20 Bibliography 22 초 록 24석

Quantifying Performance in Fading Channels Using the Sampling Property of a Delta Function

We apply the sampling property of a delta function to obtain the probability of error in fading channels. Our approach reduces the integration to a sampling. The sampling point is obtained in terms of fading parameters and the average signal-to-noise ratio (SNR) to provide the closed form solution of the performance

Costs of chronic disease and an alternative to reduce these costs: case study of End Stage Renal Disease (ESRD)

An improved understanding of the costs of diseases is obtained by conducting a case study of the costs associated with end stage renal disease (ESRD). In estimating the costs of ESRD, the costs incurred by both patients and their primary unpaid caregivers are calculated. Most economic studies of the costs of diseases ignore either the patients or unpaid caregiver side, focusing on one or the other. From a theoretical standpoint, it is shown unpaid caregiving lowers the costs of diseases to society. Unpaid caregiver lowers the cost, because for unpaid caregiving to occur, the net benefits of unpaid caregiving must be lower than the net benefits of hiring a paid caregiver. Using patients and their primary caregivers at the Gambro Dialysis Center in College Station, Texas as a case study, estimated total ESRD costs range from $84,000 to$121,000 / year / case. The distribution of these costs is positively skewed. Of the total costs, approximately 2% to 25% can be attributed to unpaid caregiving. Excluding direct medical costs in total ESRD costs, unpaid caregiving is 14% to 65% of total ESRD costs. Consideration of unpaid caregiving costs is, therefore, an important component of the costs of diseases. These estimates are conservative as the costs associated with lifestyle changes and health effects are noted, but no monetary value is placed on them. Results also indicate the patients and caregivers perception of the quantity of caregiving varies. An alternative water supply system to improve the efficiency of water supply systems taking into account water pricing, marketing, and treatment costs is proposed. This system treats and supplies water differently depending on the source of the water and if the end-use of the water is a potable or non-potable use, then may reduce treatment costs. Decreased treatment costs may make more stringent water standards more affordable. More stringent water standards may cause a decrease in the risk of water-related diseases including ESRD induced by water-borne toxins. Reducing the risk of ESRD will reduce societys costs associated with chronic illnesses. Possible benefits and costs of the proposed system are discussed, but not calculated

An Investigation of the Applicability of the Uses and Gratifications Theory for Providing Insight into e-Tourists’ Use of Smartphones

Despite the previous smartphone research in the context of travel and tourism, there is limited research based on a strong theoretical background that seeks to understand how tourists are motivated and satisfied via smartphone use. This study extended previous studies by systematically investigating and quantitatively measuring how and to what extent tourists are gratified (satisfied) by the use of smartphones during their trips based on the Uses and Gratifications Theory. According to this theory, individuals choose a media platform with the anticipation that it will aid them in realizing a specific intention, the satisfaction of this need being referred to as gratification (Green 2014; Logan, 2017; Stacks & Salwen, 2009). This study investigated four constructs in terms of antecedents (i.e., motivations of using smartphones by tourists) and consequences (i.e., satisfaction with smartphones use by tourists, satisfaction referred to as gratifications). This study adopted the Uses and Gratifications Theory as a theoretical framework to explore the use of smartphones by tourists and to measure quantitatively their touristic satisfaction. U&G motivations (Social Interaction, Entertainment, Convenience, and Information) and hypotheses were developed. The respondents of the main study were tourists traveling in downtown Greenville, South Carolina, who have experiences using smartphones at the destination. To test the model for the study, a multilevel analysis (multilevel SEM) was employed to avoid statistical biases caused by common traits within group tourists and to measure potential group effects. This study also analyzed multilevel mediation in the structural equation model. It was hypothesized that the attitude construct mediates the relationship between motivations of using smartphones by tourists (independent variable or predictors) and satisfactions with smartphones use by tourists (dependent variable) in the structural model. Moreover, the relationships among constructs were tested and examined based on the theoretical background developed through a review of the literature. This study provides a classification of motivations of using smartphone use by tourists (U&G motivations) and a newly developed scale to measure satisfaction with smartphone use by tourists and their experiences, and thus it may enhance deeper our understanding of motivations of using smartphone by tourists, attitude toward the smartphone use by tourists and satisfactions with smartphone use by tourists. This study addressed specific aspects of tourism experiences. The results suggest that U&G motivations have a significant effect on tourists’ attitude toward smartphone use, which, in turn, significantly affects e-tourist satisfaction at the individual level. However, there was no group effect among U&G motivations, the attitude toward smartphone use and e-tourist satisfaction. Based on the results from this study, the most important reason that tourists used their smartphones was to obtain information during their trips to Greenville, SC. The results of this study provide practical and theoretical implications for e- tourism communication and tourism marketing

INTEGRATED AQUIFER VULNERABILITY ASSESSMENT OF NITRATE CONTAMINATION IN CENTRAL INDIANA

Groundwater is not easily contaminated, but it is difficult to restore once contaminated. Therefore, groundwater management is important to prevent pollutants from reaching groundwater. A common step in developing groundwater management plans is assessment of aquifer risk using computational models. Groundwater modeling with a geographic information system (GIS) for efficient groundwater management can provide maps of regions where groundwater is contaminated or may be vulnerable and also can help select the optimal number of groundwater monitoring locations