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Stock-Price Forecasting Based on XGBoost and LSTM

丛书名： Springer Handbooks

2006年

作者： hoang pham

来源：畅想之星图书光盘版（南... 评论

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Computer Systems Science & Engineering 2022年第1期40卷 237-246页

作者： pham hoang Vuong Trinh Tan Dat Tieu Khoi Mai pham hoang Uyen pham The Bao Information Science Faculty Sai Gon UniversityHo Chi Minh City700000Vietnam University of Economics and Law Ho Chi Minh City700000Vietnam

Using time-series data analysis for stock-price forecasting(SPF)is complex and challenging because many factors can influence stock prices(e.g.,inflation,seasonality,economic policy,societal behaviors).Such factors can be analyzed over time for *** learning and deep learning have been shown to obtain better forecasts of stock prices than traditional *** study,therefore,proposed a method to enhance the performance of an SPF system based on advanced machine learning and deep learning ***,we applied extreme gradient boosting as a feature-selection technique to extract important features from high-dimensional time-series data and remove redundant ***,we fed selected features into a deep long short-term memory(LSTM)network to forecast stock *** deep LSTM network was used to reflect the temporal nature of the input time series and fully exploit future con-textual *** complex structure enables this network to capture more stochasticity within the stock *** method does not change when applied to stock data or Forex *** results based on a Forex dataset covering 2008–2018 showed that our approach outperformed the baseline autoregressive integrated moving average approach with regard to mean absolute error,mean squared error,and root-mean-square error.

关键词： stock-price forecasting ARIMA XGBoost LSTM deep learning

Improving Energy and Power Efficiency Using NComputing and Approaches for Predicting Reliability of Complex Computing Systems

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International Journal of Automation and computing 2010年第2期7卷 153-159页

作者： hoang pham hoang pham Jr. Department of Industrial and Systems Engineering Rutgers University Timothy Christian School

Opting to follow the computing-design philosophy that the best way to reduce power consumption and increase energy efficiency is to reduce waste, we propose an architecture with a very simple ready-implementation by using an NComputing device that can allow multi-users but only one computer is needed. This intuitively can save energy, space as well as cost. In this paper, we propose a simple and realistic NComputing architecture to study the energy and power-efficient consumption of desktop computer systems by using the NComputing device. We also propose new approaches to estimate the reliability of k-out-of-n systems based on the delta method. The k-out-of-n system consisting of n subsystems works if and only if at least k-of-the-n subsystems work. More specificly, we develop approaches to obtain the reliability estimation for the k-out-of-n systems which is composed of n independent and identically distributed subsystems where each subsystem （or energy-efficient usage application） can be assumed to follow a two-parameter exponential lifetime distribution function. The detailed derivations of reliability estimation of k-out-of-n systems based on the biased-corrected estimator, known as delta method, the uniformly minimum variance unbiased estimate （UMVUE） and maximum likelihood estimate （MLE） are discussed. An energy-management NComputing application is discussed to illustrate the reliability results in terms of the energy consumption usages of a computer system with qua（t-core, 8 GB of RAM, and a GeForce 9800GX-2 graphics card to perform various complex applications. The estimated reliability values of systems based on the UMVUE and the delta method differ only slightly. Often the UMVUE of reliability for a complex system is a lot more difficult to obtain, if not impossible. The delta method seems to be a simple and better approach to obtain the reliability estimation of complex systems. The results of this study also show that, in practice, the NComputing archite

关键词： Energy efficiency Ncomputing k-out-of-n system exponential distribution reliability estimation uniformly minimum variance unbiased estimate (UMVUE) maximum likelihood estimate (MLE).

An Imperfect-debugging Fault-detection Dependent-parameter Software

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International Journal of Automation and computing 2007年第4期4卷 325-328页

作者： hoang pham Department of Industrial and Systems Engineering Rutgers UniversityNew JerseyNJ 08855-8018USA

Software reliability growth models （SRGMs） incorporating the imperfect debugging and learning phenomenon of developers have recently been developed by many researchers to estimate software reliability measures such as the number of remaining faults and software reliability. However, the model parameters of both the fault content rate function and fault detection rate function of the SRGMs are often considered to be independent from each other. In practice, this assumption may not be the case and it is worth to investigate what if it is not. In this paper, we aim for such study and propose a software reliability model connecting the imperfect debugging and learning phenomenon by a common parameter among the two functions, called the imperfect-debugging fault-detection dependent-parameter model. Software testing data collected from real applications are utilized to illustrate the proposed model for both the descriptive and predictive power by determining the non-zero initial debugging process.

关键词： Non-homogeneous Poisson process software reliability growth least squares estimate predictive power predictive-ratio risk.

A THREE-PARAMETER FAULT-DETECTION SOFTWARE RELIABILITY MODEL WITH THE UNCERTAINTY OF OPERATING ENVIRONMENTS

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Journal of Systems Science and Systems Engineering 2017年第1期26卷 121-132页

作者： Kwang Yoon Song In Hong Chang hoang pham Department of Computer Science and Statistics Chosun University Gwangju 62022 Korea Department of Industrial and Systems Engineering Rutgers University NJ 08855-8018 USA

As requirements for system quality have increased, the need for high system reliability is also increasing. Soflnvare systems are extremely important, in terms of enhanced reliability and stability, for providing high quality services to customers. However, because of the complexity of software systems, soft-ware development can be time-consuming and expensive. Many statistical models have been developed in the past years to estimate soflnvare reliability. In this paper, we propose a new three-parameter fault-detection software reliability model with the uncertainty of operating environments. The explicit mean value function solution for the proposed model is presented. Examples are presented to illustrate the goodness-of-fit of the proposed model and several existing non-homogeneous Poisson process （NHPP） models based on three sets of failure data collected from software applications. The results show that the proposed model fits significantly better than other existing NHPP models based on three criteria such as mean squared error （MSE）, predictive ratio risk （PRR）, and predictive power （PP）.

关键词： Nonhomogeneous Poisson process ratio risk predictive power fault detection software reliability mean squared error predictive

Evidence based medicine:clinical trials that guide the management of ST-elevation myocardial infarction of elderly patients

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Journal of Geriatric Cardiology 2006年第2期3卷 120-127页

作者： hoang pham James Nguyen Thach Nguyen St.Mary Medical Center 1500 South Lake Park AveHobart IN 46342USA.

　　Cardiovascular disease is the most frequent diagnosis in elderly people and is the leading cause of death in both men and women older than 65 years. Every year in the United States more than 700,000 patients arrive at the emergency room with ST-segment elevation myocardial infarction(STEMI). About 60 percent of hospital admissions for AMI are of people older than 65 years. Their in-hospital, 1-month,and 1-year mortality is high. 1 In this article, we will provide a review on clinical trials that guide the management of STelevation myocardial infarction of the elderly patients.……

关键词： STEMI Evidence based medicine PCI AMI TIMI UFH CHF

Dynamic response of honeycomb-FGS shells subjected to the dynamic loading using non-polynomial higher-order IGA

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Defence Technology（防务技术） 2024年第7期37卷 149-161页

作者： pham Binh Le Trung-Thanh Tran Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam

The main goal of this study is to use higher-order isogeometric analysis(IGA)to study the dynamic response of sandwich shells with an auxetic honeycomb core and two different functionally graded materials(FGM)skin layers(namely honeycomb-FGS shells)subjected to dynamic ***'s non-polynomial higher-order shear deformation theory(HSDT)is used due to its simplicity and *** governing equation is derived from Hamilton's *** verifying the present approach,the effect of input parameters on the dynamic response of honeycomb-FGS shells is carried out in detail.

关键词： IGA Elastic foundation Dynamic response FGM Auxetic honeycomb Shell

Assessment of Hydrological Drought Using the Standardized Streamflow Index (SSFI): A Case Study of the Tien Yen River Basin of Quang Ninh Province, Vietnam

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Journal of Geoscience and Environment Protection 2022年第8期10卷 309-326页

作者： Nguyen Van Hieu Nguyen Van Tuan Nguyen Khac Bang pham hoang Hai Le Vinh Ha Tran Thi Hoa Institute of Water Resources Planning Ha Noi Vietnam Institute of Environment and Public Health VUSTA Ha Noi Vietnam Thai Binh University Thai Binh Province Thai Binh Vietnam

Probabilistic assessment of drought plays an important role in providing valuable information for evaluating water resources systems under drought conditions, and bivariate copulas are effective and efficient for the probabilistic assessment of drought based on joint distributions and/or joint return periods of drought characteristics. In this study, hydrological drought events and their characteristics (including duration and severity) in the Tien Yen River Basin of Quang Ninh province are detected using the Standardized Streamflow Index (SSFI). The BB8Copula is selected as the best-fit copula for hydrological drought duration and severity. Joint probabilities and joint return periods of drought duration and severity in the cases “and” and “or” are calculated based on the BB8Copula, which are employed for drought assessment. The results show that the drought events with 1-season or cross-quarter duration were more popular than others;joint probabilities and joint return periods of the detected drought events from 1962 to 2009, ranged from 0.2% to 92.2% and from 0.782 years to 315.414 years, respectively, in the case “and”, and ranged from 3.8% to 99.6% and from 0.724 years to 18.785 years, respectively, in the case “or”.

关键词： Probabilistic Assessment Standardized Streamflow Index (SSFI) Hydrological Drought Drought Characteristics Copula

Fly boyz,hybrid artists or cool guys:testing the boundaries of imagination

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Journal of Geriatric Cardiology 2005年第3期2卷 191-192页

作者： Thach Nguyen hoang pham James Nguyen Bikash Agarwal St Mary Medical Center Hobart IN Long Island College Hospital Brooklyn NY St Anthony Memorial Health Center Michigan City IN

In the early years of coronary interventions,when a single lesion was found,the question then was asked whether it was feasible and safe to dilate right away the lesion with plain old balloon angioplasty (ad hoc POBA) or to call in a senior interventional cardiologist to do POBA on a later *** lesions were found in more than one coronary artery territories,then the interventional cardiologists had to pull his or her hair and asked whether it was feasible and safe to dilate right away the other lesion(s) at the same *** than 20 years later,at this present time,with nearly perfect outcomes due to stent availability and high level of experiences from operators,the question of multiple coronary stenting in one session is neither problematic nor ***,if not all lesions are taken care immediately or in near future sessions,the question would be whether the patient receives standard of care as there is no complete revascularization.

关键词： PCI than

Association between the Phenotypes and Genotypes of Antimicrobial Resistance in Haemophilus parasuis Isolates from Swine in Quang Binh and Thua Thien Hue Provinces, Vietnam

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Engineering 2020年第1期6卷 40-48页

作者： Chao Nguyen Van Lijun Zhang Tam Vu Thi Thanh Hung pham hoang Son Tuan Tran Ngoc Qi Huang Rui Zhou State Key Laboratory of Agricultural Microbiology College of Veterinary MedicineHuazhong Agricultural UniversityWuhan 430070China Faculty of Animal Science and Veterinary Medicine University of Agricultural and ForestryHue UniversityHue 53000Vietnam Mientrung Institute for Scientific Research Vietnam Academy of Science and TechnologyHue 53000Vietnam Guangdong Provincial Key Laboratory of Marine Biology Shantou UniversityShantou 515063China Cooperative Innovation Center of Sustainable Pig Production Wuhan 430070China International Research Center for Animal Diseases The Ministry of Science and TechnologyWuhan 430070China

Haemophilus parasuis (H. parasuis) is one of the bacterial pathogens of great concern as it causes huge economic losses to the swine industry worldwide. One of the reasons why the control of H. parasuis has failed is the increase in antimicrobial resistance (AMR). The country of Vietnam has the second-largest pig production in Asia. However, there is still a lack of data about the AMR prevalence of H. parasuis in *** purpose of this study is to investigate the prevalence of AMR and analyze the association between AMR and AMR genes (ARGs). The H. parasuis strains used in this research were isolated from swine in the Quang Binh and Thua Thien Hue Provinces, Central Vietnam, as reported in our previous study. All of the strains were tested for AMR against 25 antibacterial agents using the broth microdilution method and for the presence of ARGs using the polymerase chain reaction (PCR) method. The tested strains were shown to have a high frequency of resistance to trimethoprim/sulfamethoxazole (94.6%), followed by resistance to colistin, chloramphenicol, gentamicin, penicillin, lincomycin, and amoxicillin. The most prevalent ARGs in these strains were blaTEM-1 (94.6%), int (76.8%), gyrA (58.9%), and rmtD (50.0%). Cefuroxime, chloramphenicol, and tobramycin resistances were strongly correlated with the presence of the ARGs blaROB-1 (odds ratio (OR) = 26.3, 95% confidence interval (CI) 2.7–255.7, p = 0.002), catl (OR = 25.1, 95% CI 2.4–258.9, p = 0.004), and strB (OR = 23.5, 95% CI 2.6–212.6, p = 0.001), *** study reveals for the first time the current situation of H. parasuis AMR in Central Vietnam, which is helpful for the clinical control of this disease, as well as for the development of policies and clinical practice guidelines to reduce AMR in swine production in Central Vietnam.

关键词： Haemophilus parasuis Antimicrobial resistance Antimicrobial resistance gene Vietnam