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This paper proposes an algorithm to find robust reliability-based topology optimized designs under a random-field material model. The initial design domain is made of linear elastic material whose property, i.e., Young's modulus, is... more
This paper proposes an algorithm to find robust reliability-based topology optimized designs under a random-field material model. The initial design domain is made of linear elastic material whose property, i.e., Young's modulus, is modeled by a random field. To facilitate computation, the Karhunen-Lo\`eve expansion discretizes the modeling random field into a small number of random variables. Robustness is achieved by optimizing a weighted sum of mean and standard deviation of a quantity of interest, while reliability is employed through a probabilistic constraint. The Smolyak-type sparse grid and the stochastic response surface method are applied to reduce computational cost. Furthermore, an efficient inverse-reliability algorithm is utilized to decouple the double-loop structure of reliability analysis. The proposed algorithm is tested on two common benchmark problems in literature. Finally, Monte Carlo simulation is used to validate the claimed robustness and reliability of ...
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SYNOPSIS This study examines how auditors react to clients' engagement in classification shifting which refers to the intentional misallocation of line items within the income statement. We find that classification shifting is... more
SYNOPSIS This study examines how auditors react to clients' engagement in classification shifting which refers to the intentional misallocation of line items within the income statement. We find that classification shifting is positively associated with audit fees, audit report lags, the issuance of a modified audit opinion, and auditor resignations. Additional analyses show that auditors' responses to multiple-year classification shifting are similar to our main findings. We further find that classification shifting is associated with a higher likelihood of financial misstatements in the classification shifting year, and future announcements of financial restatements. We also find that the probability of future restatements is even higher when audit clients engage in both classification shifting and real earnings management. Overall, our results imply that auditors become more cautious in response to audit clients' classification shifting behavior. Data Availability: Da...
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STUDY OBJECTIVE To investigate the association of unintentional dural puncture (UDP) and postdural puncture headache (PDPH) with the risk of chronic headache, backache, neckache and depression. We also investigated if epidural blood patch... more
STUDY OBJECTIVE To investigate the association of unintentional dural puncture (UDP) and postdural puncture headache (PDPH) with the risk of chronic headache, backache, neckache and depression. We also investigated if epidural blood patch (EBP) is associated with reduced risk of these morbidities. DESIGN Systematic review and meta-analysis. PATIENTS Pregnant women who experienced UDP and/or PDPH versus those who had uneventful neuraxial procedures, and women who received EBP versus those who did not. INTERVENTIONS None. MEASUREMENTS Primary outcomes were headache, backache, and neckache lasting ≥12 months, and depression ≥1 month. Secondary outcomes included chronic headache, backache, and neckache persisting ≥1 and ≥ 6 months, and the effects of EBP on those outcomes at ≥1 and ≥ 12 months. Subgroup analyses of prospective studies and sensitivity analyses of primary outcomes excluding poor quality studies were performed. MAIN RESULTS Twelve studies compared 6541 women with UDP and/or PDPH versus 1,004,510 with uncomplicated neuraxial procedures. Eight studies compared EBP (n = 3610) with no EBP (n = 3154). UDP and/or PDPH were associated with increased risk of headache (RR 3.95; 95%CI 2.13 to 7.34; I2 42%), backache (RR 2.72; 95%CI 2.04 to 3.62; I2 1%), and neckache (RR 8.09; 95%CI 1.03 to 63.35) persisting ≥12 months, and depression (RR 3.12; 95%CI 1.44 to 6.77; I2 90%) lasting ≥1 month. Results were consistent in analyses at ≥1 and ≥ 6 months, subgroup analyses of prospective studies, and after exclusion of one poor-quality study from our primary outcome. EBP was not associated with significant reduction in the risk of long-term morbidities. CONCLUSIONS UDP and/or PDPH were associated with increased risk of chronic headache, backache, neckache, and depression. EBP was not associated with a significant reduction in those risks, but this conclusion is limited by the heterogeneity of current data and lack of information on the success of EBP in relieving acute PDPH symptoms.
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We consider the value 1 problem for probabilistic automata over finite words: it asks whether a given probabilistic automaton accepts words with probability arbitrarily close to 1. This problem is known to be undecidable. However,... more
We consider the value 1 problem for probabilistic automata over finite words: it asks whether a given probabilistic automaton accepts words with probability arbitrarily close to 1. This problem is known to be undecidable. However, different algorithms have been proposed to partially solve it; it has been recently shown that the Markov Monoid algorithm, based on algebra, is the most correct algorithm so far. The first contribution of this paper is to give a characterisation of the Markov Monoid algorithm. The second contribution is to develop a profinite theory for probabilistic automata, called the prostochastic theory. This new framework gives a topological account of the value 1 problem, which in this context is cast as an emptiness problem. The above characterisation is reformulated using the prostochastic theory, allowing to give a modular proof. 1 Introduction Rabin [9] introduced the notion of probabilistic automata, which are finite automata with randomised transitions. This ...
Most of the multiscale topology optimization (TO) approaches, which have been proposed for multi-material designs, are based on the assumption of deterministic loads and the exclusion of uncertain quantities like positions, directions,... more
Most of the multiscale topology optimization (TO) approaches, which have been proposed for multi-material designs, are based on the assumption of deterministic loads and the exclusion of uncertain quantities like positions, directions, and magnitudes of loads. This contribution deals with: (1) multiscale design; (2) multi-materials; (3) loading uncertainties; and (4) incompressible materials such as rubbers and biological soft tissues. The proposed approach, in this paper is to exploit polytopal composite finite elements (PCEs) to overcome the inherent volumetric locking phenomenon in incompressible materials and employ adaptive geometric components (AGCs) to model porous multi-materials on an analysis grid of PCEs, which allows simultaneously optimizing incompressible multi-materials at both macro- and micro-scales. Besides the mixed displacement–pressure formulation and traditional concurrent TO, the proposed approach is purely developed from the displacement formulation and the AGCs-based direct-multiscale TO whose only constraint is global volume. The effectiveness of the current technique was demonstrated by solving several examples of incompressible porous multi-material designs under single and multiple random loads.
Script used to analyse ground counts, RPA-derived manual counts and RPA-derived semi-automated counts
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Page 1. Quantitative Approach to Using E-Commerce Data to Monitor and Control the Performance of a Supply Chain Trung T. Pham DIcentral Corporation tpham@DIcentral. com Abstract This paper presents a quantitative approach ...
Research Interests: Computer Science, Supply Chain Management, Performance Measurement, Supply Chain, Parameter estimation, and 10 moreProcess Design, Mathematical Model, Data Handling, Supply Chains, Electronic Data Interchange, E Commerce, Electronic Commerce, Time measurement, Monitoring and control, and Quantitative approach
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Data augmentation is an essential part of the training process applied to deep learning models. The motivation is that a robust training process for deep learning models depends on large annotated datasets, which are expensive to be... more
Data augmentation is an essential part of the training process applied to deep learning models. The motivation is that a robust training process for deep learning models depends on large annotated datasets, which are expensive to be acquired, stored and processed. Therefore a reasonable alternative is to be able to automatically generate new annotated training samples using a process known as data augmentation. The dominant data augmentation approach in the field assumes that new training samples can be obtained via random geometric or appearance transformations applied to annotated training samples, but this is a strong assumption because it is unclear if this is a reliable generative model for producing new training samples. In this paper, we provide a novel Bayesian formulation to data augmentation, where new annotated training points are treated as missing variables and generated based on the distribution learned from the training set. For learning, we introduce a theoretically ...
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In this work, we present, LieNet, a novel deep learning framework that simultaneously detects, segments multiple object instances, and estimates their 6D poses from a single RGB image without requiring additional post-processing. Our... more
In this work, we present, LieNet, a novel deep learning framework that simultaneously detects, segments multiple object instances, and estimates their 6D poses from a single RGB image without requiring additional post-processing. Our system is accurate and fast (∼10 fps), which is well suited for real-time applications. In particular, LieNet detects and segments object instances in the image analogous to modern instance segmentation networks such as Mask R-CNN, but contains a novel additional sub-network for 6D pose estimation. LieNet estimates the rotation matrix of an object by regressing a Lie algebra based rotation representation, and estimates the translation vector by predicting the distance of the object to the camera center. The experiments on two standard pose benchmarking datasets show that LieNet greatly outperforms other recent CNN based pose prediction methods when they are used with monocular images and without post-refinements.
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Purpose The purpose of this study is to examine the influence of the readability of annual reports on firms’ ability to obtain trade credit from suppliers. Particularly, the authors conjecture that annual report readability helps firms... more
Purpose The purpose of this study is to examine the influence of the readability of annual reports on firms’ ability to obtain trade credit from suppliers. Particularly, the authors conjecture that annual report readability helps firms obtain more trade credit from suppliers. Design/methodology/approach The authors use the Gunning Fog Index as the primary measure of annual report readability and the ratio of accounts payable to the book value of total assets as the measure of trade credit. Findings Results from the study of 4,754 firms during the 2004–2016 period indicate that suppliers extend more trade credit to firms with more readable financial reports. The authors’ results are robust to alternative measures of trade credit and annual report readability. The authors’ results remain robust when we control for firm fixed effects and potential endogeneity problems using the instrumental variable approach. A further test shows that the level of trade credit is higher for firms in bu...
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This article presents a comparison of the computing performance of the MapReduce tool Hadoop and Giraph on large-scale graphs. The main ideas of MapReduce and bulk synchronous parallel (BSP) are reviewed as big data computing approaches... more
This article presents a comparison of the computing performance of the MapReduce tool Hadoop and Giraph on large-scale graphs. The main ideas of MapReduce and bulk synchronous parallel (BSP) are reviewed as big data computing approaches to highlight their applicability in large-scale graph processing. This paper reviews the execution performance of Hadoop and Giraph on the PageRank algorithm to classify web pages according to their relevance, and on a few other algorithms to find the minimum spanning tree in a graph with the primary goal of finding the most efficient computing approach to work on large-scale graphs. Experimental results show that the use of Giraph for processing large-size graphs reduces the execution time by 25% in comparison with the results obtained using the Hadoop for the same experiments. Giraph represents the optimal option thanks to its in-memory computing approach that avoids secondary memory direct interaction.
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Aspect-oriented software development (AOSD) solves a few issues of the object-oriented software development (OOSD) approach and adds a few more concerning modules and their relationships. Join point interface (JPI) is an AOSD methodology... more
Aspect-oriented software development (AOSD) solves a few issues of the object-oriented software development (OOSD) approach and adds a few more concerning modules and their relationships. Join point interface (JPI) is an AOSD methodology that by the definition of the interface between advised artifacts and aspects solves associated AOSD issues to get software with a high modularity level. Looking for a JPI software development approach, this article proposes and exemplifies the use of JPIAspectZ, an extension of the formal aspect-oriented language AspectZ for the software JPI requirement specifications. Mainly, JPIAspectZ looks for a concept and model consistency in a JPI software development process. Since the main JPI characteristics are the joining point interfaces definitions, i. e. explicit associations definition between aspects and advised modules, thus, by JPI, classes are no longer oblivious of possible interaction with aspects, and aspects, for their action effectiveness, ...
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Đặt vấn đề: Hội chứng chuyển hóa là một tập hợp của các yếu tố nguy cơ chuyển hóa tim, có khuynh hướng nhóm lại với nhau ở các đối tượng bị ảnh hưởng hơn là dự đoán một cách tình cờ. Sự hiện diện của hội chứng chuyển hóa làm tăng đáng kể... more
Đặt vấn đề: Hội chứng chuyển hóa là một tập hợp của các yếu tố nguy cơ chuyển hóa tim, có khuynh hướng nhóm lại với nhau ở các đối tượng bị ảnh hưởng hơn là dự đoán một cách tình cờ. Sự hiện diện của hội chứng chuyển hóa làm tăng đáng kể nguy cơ xuất hiện đái tháo đường típ 2, bệnh tim mạch, từ đó liên quan chặt chẽ đến quá trình lão hóa và một loạt các kết cục xấu. Các nghiên cứu gần đây cho thấy thiếu vitamin D rất phổ biến trên thế giới và là một yếu tố nguy cơ của hội chứng chuyển hóa. Mục tiêu nghiên cứu: (1). Đặc điểm nồng độ 25-hydroxyvitamin D huyết tương ở đối tượng có hội chứng chuyển hóa. (2). Mối liên quan giữa nồng độ 25-hydroxyvitamin D huyết tương và các yếu tố nguy cơ của hội chứng chuyển hóa. Đối tượng và phương pháp nghiên cứu: Sử dụng phương pháp nghiên cứu mô tả cắt ngang có đối chứng ở 275 đối tượng người trưởng thành đến khám sức khỏe tại Trung tâm điều trị theo yêu cầu và quốc tế - Bệnh viện Trung ương Huế, trong đó nhóm bệnh gồm 94 đối tượng có hội chứng chuy...
The timeliness of financial reporting has been considered as an important factor that contributes to the well-functioning of an economy. This study extends the contemporary research stream by examining determinants of the timeliness of... more
The timeliness of financial reporting has been considered as an important factor that contributes to the well-functioning of an economy. This study extends the contemporary research stream by examining determinants of the timeliness of financial reporting process. Specifically, we investigate whether report lag is influenced by (1) the level of executive compensation; (2) the level of stock-based compensation compared to cash-based compensation, and (3) the level of executive compensation above the expected compensation level. We find that firms have shorter report lag when their level of executive compensation is higher. We also document that firms with more stock-based compensation have shorter financial reporting delays. Finally, firms with executive compensation level above the expected executive compensation are more likely to have shorter report lags. Our study underscores the importance of the type and the level of compensation as determinants of firms’ earnings reporting del...
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In the biomedical and healthcare fields, the ownership protection of the outsourced data is becoming a challenging issue in sharing the data between data owners and data mining experts to extract hidden knowledge and patterns.... more
In the biomedical and healthcare fields, the ownership protection of the outsourced data is becoming a challenging issue in sharing the data between data owners and data mining experts to extract hidden knowledge and patterns. Watermarking has been proved as a right-protection mechanism that provides detectable evidence for the legal ownership of a shared dataset, without compromising its usability under a wide range of data mining for digital data in different formats such as audio, video, image, relational database, text and software. Time series biomedical data such as Electroencephalography (EEG) or Electrocardiography (ECG) is valuable and costly in healthcare, which need to have owner protection when sharing or transmission in data mining application. However, this issue related to kind of data has only been investigated in little previous research as its characteristics and requirements. This paper proposes an optimized watermarking scheme to protect ownership for biomedical ...
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Chronic kidney disease is a complex disease, and one of its common complications is associated with hyperphosphatemia. This can lead to the development of severe hyperparathyroidism, soft tissue calcification, calcification of the lung,... more
Chronic kidney disease is a complex disease, and one of its common complications is associated with hyperphosphatemia. This can lead to the development of severe hyperparathyroidism, soft tissue calcification, calcification of the lung, morbidity, and mortality. One of the mainstream therapies for managing hyperphosphatemia are phosphate binder medications (PBMs). We did a retrospective data analysis of 150 ESRD patients who were taking PBMs. Patients were grouped into non-calcium based (e.g., sevelamer), calcium-based (e.g., calcium acetate), or both, or those patients that did not receive any PBMs. We found that Sevelamer was the most commonly used PBM (53%), and calcium acetate was the second most commonly used PBM (40%). Some patients received combination therapy.
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To report the 5-year biochemical relapse-free survival (BRFS), overall survival (OS), and long-term toxicity outcomes of patients treated with low-dose-rate (LDR) brachytherapy as monotherapy for low- to intermediate-risk prostate cancer.... more
To report the 5-year biochemical relapse-free survival (BRFS), overall survival (OS), and long-term toxicity outcomes of patients treated with low-dose-rate (LDR) brachytherapy as monotherapy for low- to intermediate-risk prostate cancer. Between 2004 and 2011, 371 patients were treated with LDR brachytherapy as monotherapy. Of these, 102 patients (27%) underwent transurethral resection of the prostate (TURP) prior to implantation. Follow-up was performed every 3 months for 12 months, then every 6 months over 4 years and included prostate specific antigen evaluation. The biochemical relapse-free survival (BRFS) was defined according to the Phoenix criteria. Acute and late toxicities were documented using the Common Terminology Criteria for Adverse Events version 4.0. The BRFS and OS estimates were calculated using Kaplan-Meier plots. Univariate and multivariate analyses were performed to evaluate outcomes by pre-treatment clinical prognostic factors and radiation dosimetry. The medi...
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A term, appropriate-for-gestational-age, male infant born via normal spontaneous vaginal delivery presented at birth with a full-body erythematous, vesiculobullous rash. He was well-appearing with normal vital signs and hypoglycemia that... more
A term, appropriate-for-gestational-age, male infant born via normal spontaneous vaginal delivery presented at birth with a full-body erythematous, vesiculobullous rash. He was well-appearing with normal vital signs and hypoglycemia that quickly resolved. His father had a history of herpes labialis. His mother had an episode of herpes zoster during pregnancy and a prolonged rupture of membranes that was adequately treated. The patient underwent a sepsis workup, including 2 attempted but unsuccessful lumbar punctures, and was started on broad-spectrum antibiotics and acyclovir, given concerns about bacterial or viral infection. The rash evolved over the course of several days. Subsequent workup, with particular attention to his history and presentation, led to his diagnosis.
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The purpose of this study was to report on the dosimetric benefits and late toxicity outcomes following injection of a hydrogel spacer (HS) between the prostate and rectum for patients treated with prostate radiotherapy. A total of 76... more
The purpose of this study was to report on the dosimetric benefits and late toxicity outcomes following injection of a hydrogel spacer (HS) between the prostate and rectum for patients treated with prostate radiotherapy. A total of 76 patients with a clinical stage of T1-T3a prostate cancer underwent general anaesthesia for fiducial marker insertion plus injection of the HS into the peri-rectal space prior to intensity modulated radiation therapy (IMRT) or volumetric modulated radiation therapy (VMAT). Spacer safety, dosimetric benefits and the immediate to long-term effects of gastrointestinal toxicity (GI) were assessed. There were no postoperative complications reported. Mean prostate size were 66.0cc (25.0cc - 187.0cc). Rectal dose volume parameters were observed with volume of rectum receiving 70Gy (rV), 75Gy (rV) and 78Gy (rV) were 7.8%, 3.6% and 0.4%. 21% (16/76) developed acute grade 1 GI toxicities but all were resolved completely by 3 months post-treatment. 3% (2/76) devel...
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Provisional and culotte are the most commonly used techniques in left main (LM) stenting. The impact of different post-dilation techniques on fluid dynamic of LM bifurcation has not been yet investigated. The aim of this study is to... more
Provisional and culotte are the most commonly used techniques in left main (LM) stenting. The impact of different post-dilation techniques on fluid dynamic of LM bifurcation has not been yet investigated. The aim of this study is to evaluate, by means of computational fluid dynamic analysis (CFD), the impact of different post-dilation techniques including proximal optimization technique (POT), kissing balloon (KB), POT-Side-POT and POT-KB-POT, 2-steps Kissing (2SK) and Snuggle Kissing balloon (SKB) on flow dynamic profile after LM provisional or culotte stenting. We considered an LM-LCA-LCX bifurcation reconstructed after reviewing 100 consecutive patients (mean age 71.4 ± 9.3 years, 49 males) with LM distal disease. The diameters of LAD and LCX were modelled according to the Finnet's law as following: LM 4.5 mm, LAD 3.5 mm, LCX 2.75 mm, with bifurcation angle set up at 55°. Xience third-generation stent (Abbot Inc., USA) was reconstructed and virtually implanted in provisional/...
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In the diagnosis and management of patients with coronary artery disease (CAD) and chronic left ventricular (LV) dysfunction or heart failure (HF), there are many uncertainties because of the non-specificity of the symptoms and signs of... more
In the diagnosis and management of patients with coronary artery disease (CAD) and chronic left ventricular (LV) dysfunction or heart failure (HF), there are many uncertainties because of the non-specificity of the symptoms and signs of HF. Usually, severe CAD causes LV dysfunction. However, not rarely, LV dysfunction is the cause or aggravation of ischemia to many subsets of patients with or without CAD. In this article, the care of patients with CAD with LV dysfunction, along with the challenges of diagnosing asymptomatic HF and the criteria for monitoring success are presented. Then the evidence of LV dysfunction triggering or aggravating ischemia is discussed. The newest methodology of assessing the venous blood volume which causes the main presentations of HF when its filling capacity is exceeded will also be presented in details. In summary, the effects of fluid mobilization by conventional medications for CAD (e.g angiotensin converting enzyme inhibitors (ACEI) or beta-blocke...
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The feeling of touch is an essential human sensation. Four types of mechanoreceptors (i.e., FA-I, SA-I, FA-II, and SA-II) in human skin signalize physical properties, such as shape, size, and texture, of an object that is touched and... more
The feeling of touch is an essential human sensation. Four types of mechanoreceptors (i.e., FA-I, SA-I, FA-II, and SA-II) in human skin signalize physical properties, such as shape, size, and texture, of an object that is touched and transmit the signal to the brain. Previous studies attempted to investigate the mechanical properties of skin microstructure and their effect on mechanoreceptors by using finite element modeling. However, very few studies have focused on the three-dimensional microstructure of dermal papillae, and this is related to that of FA-I receptors. A gap exists between conventional 2D models of dermal papillae and the natural configuration, which corresponds to a complex and uneven structure with depth. In this study, the three-dimensional microstructure of dermal papillae is modeled, and the differences between two-dimensional and three-dimensional aspects of dermal papillae on the strain energy density at receptor positions are examined. The three-dimensional ...