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Credit Scoring via Statistical and Intelligent Techniques:Empirical Evidence from Chinese SME and Agricultural Credit

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Credit Scoring via Statistical and Intelligent Techniques:Em...

作者： Tabassum habib 大连理工大学

学位级别：硕士

信用评分是决定一笔贷款发放与否的关键。信用评分若能有效反映贷款的违约可能性、则将大大减少金融机构的损失。信用评分问题本质是将违约客户和非违约客户区分开来的二分类问题。在信用评分的求解过程中,指标的遴选是否得当、分类模... 详细信息

信用评分是决定一笔贷款发放与否的关键。信用评分若能有效反映贷款的违约可能性、则将大大减少金融机构的损失。信用评分问题本质是将违约客户和非违约客户区分开来的二分类问题。在信用评分的求解过程中,指标的遴选是否得当、分类模型的构建是否合理,对违约状态的准确预测起着重要的作用。本研究旨在研究如何将指标遴选与分类模型构建进行结合,从而构建一套判别能力强的信用评分模型。本研究采用的指标筛选方法包括最小绝对收缩选择算子（LASSO）、多元自适应回归样条（MARS）,分类模型包括分类回归树（CART）、逻辑回归（LR）、人工神经网络（ANN）以及支持向量机（SVM）。本研究基于中国中小企业贷款数据和中国农户贷款数据,对指标筛选方法与分类模型构建方法如何结合进行实证研究。结果表明,以LASSO方法进行指标筛选、支持向量机SVM进行分类模型构建的信用评分模型,明显优于其他指标筛选与分类模型的组合方法。此外,本研究还证明了:（1）指标筛选能够明显提高人工神经网络ANN的分类精度;（2）基于LAS SO的指标筛选能改善逻辑回归LR的分类效果;（3）指标筛选并不能提高分类回归树CART的分类准确性。本研究通过四种广泛使用的分类模型构建方法以及两种前沿的指标筛选方法,为信用评分指标筛选与分类模型如何有效结合提供了证据。应该指出,本研究所给出的指标筛选与分类模型的组合,是在特征各异的数据集基础上实证检验得到的,数据集在是否为平衡样本、指标数量多寡、以及研究对象上都各有区别。本研究与其他研究的不同,在于本研究是基于中国中小企业贷款数据以及农户贷款数据进行建模,并基于公共数据集上进行模型验证。本研究提出的信用评分模型,可为贷款机构制定有效的信用风险管理政策提供参考。

关键词：信用评分统计技术智能方法指标筛选最小绝对收缩和选择算子支持向量机

Existence and Global Asymptotic Behavior of Positive Solutions for Sublinear and Superlinear Fractional Boundary Value Problems

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Chinese Annals of Mathematics,Series B 2016年第1期37卷 1-28页

作者： Imed BACHAR habib MAAGLI Faten TOUMI Zagharide ZINE EL ABIDINE Mathematics Department College of Science King Saud University P.O.Box 2455 Riyadh 11451 Saudi Arabia. Department of Mathematics College of Sciences and Arts Rabigh Campus King Abdulaz University P.O.Box 344 Rabigh 21911 Saudi Arabia. Departement de Mathematiques Faculte des Sciences de Tunis Campus Universitalre 2092 Tunis Tunisia.

In this paper, the authors aim at proving two existence results of fractional differential boundary value problems of the form （Pa,bα）{D^au（x）＋f（x,u（x））=0,x∈（0,1）,u（0）=u（1）=0,D^a-3u（0）=a,u^（1）=-6where 3 ≤ a 〈 4, D^ is the standard Riemann-Liouville fractional derivative and a, b are nonnegative constants. First the authors suppose that f（x, t） = -p（x）t^σ, with cr ~ （-1, 1） and p being a nonnegative continuous function that may be singular at x - 0 or x - 1 and satisfies some conditions related to the Karamata regular variation theory. Combining sharp estimates on some potential functions and the Sch^uder fixed point theorem, the authors prove the existence of a unique positive continuous solution to problem （P0,0）. Global estimates on such a solution are also obtained. To state the second existence result, the authors assume that a, b are nonnegative constants such that a ＋ b 〉 0 and f（x, t） -= tφ（x, t）, with φ（x, t） being a nonnegative continuous function in （0, 1） × [0, ∞） that is required to satisfy some suitable integrability condition. Using estimates on the Green＇s function and a perturbation argument, the authors prove the existence and uniqueness of a positive continuous solution u to problem （Pa,b）, which behaves like the unique solution of the homogeneous problem corresponding the existence results. to （Pa,b）. Some examples are given to illustrate the existence results.,

关键词： Fractional differential equation Positive solution Fractional Green's function Karamata function Perturbation arguments Sch/iuder fixad point theorem

Umbilical cord blood stem cell treatment for a patient with psoriatic arthritis

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World Journal of Stem Cells 2017年第12期9卷 235-240页

作者： Margaret Coutts Rowena Soriano Rajendran Naidoo habib Torfi Invitrx Therapeutics IrvineCA 92618United States

Clinical and laboratory results document psoriatic arthritis in a 56-year old patient. The symptoms did not resolve with standard treatments(nonsteroidal anti-inflammatory drugs, steroids and methotrexate). TNF-alpha inhibitors(certolizumab pegol and adalimumab) were added to the treatment regime, with some adverse effects. A trial of human umbilical cord stem cell therapy was then initiated. The stem cells were enriched and concentrated from whole cord blood, by removal of erythrocytes and centrifugation. The patient received several infusions of cord blood stem cells, through intravenous and intra-articular injections. These stem cell treatments correlated with remission of symptoms(joint pain and psoriatic plaques) and normalized serologic results for the inflammatory markers C-reactive protein and erythrocyte sedimentation rate. These improvements were noted within the first thirty days post-treatment, and were sustained for more than one year. The results of this trial suggest that cord blood stem cells may have important therapeutic value for patients with psoriatic arthritis, particularly for those who cannot tolerate standard treatments.

关键词： Umbilical cord blood stem cells Stem cells Psoriatic arthritis Rheumatoid arthritis

Serious games in science education:a systematic literature review

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Virtual Reality & Intelligent Hardware 2022年第3期4卷 189-209页

作者： Mohib ULLAH Sareer Ul AMIN Muhammad MUNSIF Muhammad Mudassar YAMIN Utkurbek SAFAEV habib KHAN Salman KHAN habib ULLAH Department of Computer Science Norwegian University of Science and Technology2815 GjøvikNorway Department of Computer Science Islamia College University Peshawar25000 Pakistan Department of Information Security and Communication Norwegian University of Science and Technology2815 GjøvikNorway Faculty of Science and Technology Norwegian University of Life Sciences1430ÅsNorway

Teaching science through computer games,simulations,and artificial intelligence(AI)is an increasingly active research *** this end,we conducted a systematic literature review on serious games for science education to reveal research trends and *** discussed the role of virtual reality(VR),AI,and augmented reality(AR)games in teaching science subjects like ***,we covered the research spanning between 2011 and 2021,investigated country-wise concentration and most common evaluation methods,and discussed the positive and negative aspects of serious games in science education in particular and attitudes towards the use of serious games in education in general.

关键词： Serious games Simulations,Artificial intelligence,Virtual reality,Augmented reality Games in education

Metals and metalloid bioconcentrations in the tissues of Typha latifolia grown in the four interconnected ponds of a domestic landfill site

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Journal of Environmental Sciences 2017年第4期29卷 56-68页

作者： Zohra Ben Salem Xavier Laffray Ahmed Al-Ashoor habib Ayadi Lotfi Aleya Bourgogne Franche-Comte University Chrono-Environnement Laboratory UMR CNRS 6249 F-25030 Besancon Cedex France Paris Est-Creteil University IPE team iEES Paris UMR 7618 F-94010 Creteil Cedex Prance Thi Qar University IQ-64001 AI Nasiriyah Iraq Sfax University LR/UR/05ES05 Biodiversity and Aquatic Ecosystem BP 1171 CP 3000 Sfax Tunisia

The uptake of metals in roots and their transfer to rhizomes and above-ground plant parts（stems, leaves） of cattails（Typha latifolia L.） were studied in leachates from a domestic landfill site（Etueffont, France） and treated in a natural lagooning system. Plant parts and corresponding water and sediment samples were taken at the inflow and outflow points of the four ponds at the beginning and at the end of the growing season. Concentrations of As, Cd, Cr, Cu, Fe, Mn, Ni and Zn in the different compartments were estimated and their removal efficiency assessed, reaching more than 90% for Fe, Mn and Ni in spring and fall as well in the water compartment. The above-and below-ground cattail biomass varied from 0.21 to 0.85, and 0.34 to 1.24 kg dry weight/m^2, respectively, the highest values being recorded in the fourth pond in spring 2011. The root system was the first site of accumulation before the rhizome, stem and leaves. The highest metal concentration was observed in roots from cattails growing at the inflow of the system＇s first pond. The trend in the average trace element concentrations in the cattail plant organs can generally be expressed as： Fe 〉 Mn 〉 As 〉 Zn 〉 Cr 〉 Cu 〉 Ni 〉 Cd for both spring and fall. While T. latifolia removes trace elements efficiently from landfill leachates, attention should also be paid to the negative effects of these elements on plant growth.

关键词： Landfill leachate Lagooning Trace elements Typha latifolia Phytoremediation

An experimental study on the effects of physical,mechanical,and electrochemical properties of natural cohesive soils on critical shear stress and erosion rate

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International Journal of Sediment Research 2016年第01期31卷 1-15页

作者： Navid Kimiaghalam Shawn P.Clark habib Ahmari Department of Civil Engineering University of Manitoba Water Resources Department Manitoba Hydro

The field of cohesive sediment erosion is still not fully understood,in large part due to the many soil parameters that affect cohesive sediment *** this study several undisturbed natural soil samples were taken from different river banks in Manitoba,*** samples mainly contained clay and silt with 24-94%clay content,thus the study covered a wide range of cohesive *** each sample13 different physical,mechanical,and electrochemical properties were *** shear stress of erosion and erosion rate were quantified using an Erosion Measurement Device(EMD).Stepwise regression was used to find the variables most significantly correlated to critical shear stress and erosion rate,which led to the development of a new empirical equation to estimate the critical shear stress of cohesive *** was found that the critical shear stress is highly correlated with cohesion,while both cohesion and sodium adsorption ratio(SAR)had significant influence on the erosion rate.

关键词： Cohesive sediment Critical shear stress Erosion rate

A Soil Moisture Data Assimilation System for Pakistan Using PODEn4DVar and CLM4.5

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Journal of Meteorological Research 2019年第6期33卷 1182-1193页

作者： Tariq MAHMOOD Zhenghui XIE Binghao JIA Ammara habib Rashid MAHMOOD State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Pakistan Meteorological Department Islamabad 44000Pakistan Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Science and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Soil moisture is an important state variable for land–atmosphere *** is a vital land surface variable for research on hydrology,agriculture,climate,and drought *** current study,a soil moisture data assimilation framework has been developed by using the Community Land Model version 4.5(CLM4.5)and the proper orthogonal decomposition(POD)-based ensemble four-dimensional variational assimilation(PODEn4 DVar)*** experiments were conducted at four agricultural sites in Pakistan by assimilating in-situ soil moisture *** results showed that it was a reliable *** quantify further the feasibility of the data assimilation(DA)system,soil moisture observations from the top four soil-depths(0–5,5–10,10–20,and 20–30 cm)were *** evaluation results indicated that the DA system improved soil moisture *** addition,updating the soil moisture in the upper soil layers of CLM4.5 could improve soil moisture estimation in deeper soil layers[layer 7(L7,62.0 cm)and layer 8(L8,103.8 cm)].To further evaluate the DA system,observing system simulation experiments(OSSEs)were designed for Pakistan by assimilating daily *** idealized experiments produced statistical results that had higher correlation coefficients,reduced root mean square errors,and lower biases for assimilation,which showed that the DA system is able to produce and improve soil moisture estimation in Pakistan.

关键词： PODEn4DVar Community Land Model version 4.5 data assimilation soil moisture Pakistan

Sublethal effects of hexaflumuron on development and reproduction of the diamondback moth, Plutella xylostella （Lepidoptera： Yponomeutidae）

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Insect Science 2011年第6期18卷 689-696页

作者： Mohammad Mahmoudvand habib Abbasipour Aziz Sheikhi Garjan Ali Reza Bandani Department of Plant Protection Faculty of Agricultural Sciences Shahed University Tehran Iranian Research Institute of Plant Protection Tehran Department of Plant Protection College of Agriculture and Natural Resources University of Tehran Karaj Islamic Azad University Qom branch Young Researches Club Qom Iran

Effects of hexaflumuron at 10% lethal concentration （LC10） and LC25 on development and reproduction parameters of the diamondback moth, Plutella xylostella （Linnaeus, 1753）（Lep.： Yponomeutidae） were investigated. Estimated LC50, LC10 and LC25 values of leaf dip bioassay of hexaflumuron on the third instar larvae of the P xylostella were 1.48, 0.59 and 0.91 mg/L, respectively. Hexaflumuron decreased pupal weight in the parent generation at sublethal concentrations but in the offspring generation, this effect was not observed. Sublethal concentrations increased egg, first and second larval instar and pupa developmental time and shortened life span of adults, but did not change the third and fourth larval instars and pre-pupa developmental period. Also fecundity of females reduced significantly but hatchability of treatments and control were similar. Survival rate of pre-adult stages declined significantly at LC25 concentration. Reproduction parameters such as reproductive rate （R0） and intrinsic rate of increase in sublethal concentrations were significantly lower compared with control, but gross reproduction rate （GRR） at the LC10 concentration was increased and it could be hormoligosis. Also hexaflumuron significantly increased doubling time （Dt）. We conclude that the sublethal effects of hexaflumuron might exhibit significant effects on the population dynamics of P xylostella.

关键词： biological parameters diamondback moth hormoligosis IGR Plutella xylostella sublethal concentrations

Relationship between high sensitivity C-reactive protein and angiographic severity of coronary artery disease

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Journal of Geriatric Cardiology 2020年第5期17卷 256-263页

作者： Nadia Bouzidi Mejdi Ben Messaoud Faouzi Maatouk habib Gamra Salima Ferchichi University of Monastir Faculty of PharmacyClinical and Molecular Biology UnitMonastirTunisia University of Monastir Cardiology A Department Fattouma Bourguiba University HospitalCardiothrombosis Research LaboratoryTunisia University of Monastir Cardiology B Department Fattouma Bourguiba University HospitalCardiothrombosis Research LaboratoryTunisia

Background Coronary artery disease(CAD)remains a leading cause of morbidity and *** play a potential role in atherosclerosis pathogenesis and *** investigated the association between high sensitive C-reactive protein(hs CRP)and severity of *** CAD patients were stratified according to hs CRP cut-off value into high levels hs CRP group(≥8.4 mg/L)and low levels hs CRP group(<8.4 mg/L).Severity of CAD was assessed according to artery stenosis degree and the number of vessel *** analysis was performed using Statistical Package for the Social Sciences(SPSS,version 23.0).Results The mean age was 60.3±11.0 *** level of hs CRP was increased and ranged from 0.2 to 1020.0 mg/*** risk factors and severity of CAD didn’t show significant differences between the two *** multivariate linear analysis,cardiac troponin I(c Tn I)and serum amyloid A(SAA)were predictors of hs *** shown in receiver operating characteristic(ROC)curve analysis performed in patients with ST-segment elevation myocardial infarction(STEMI)and compared to myonecrosis biomarkers,hs CRP(area under the curve(AUC):0.905;95%CI:0.844-0.966;P<0.001)could be a powerful predictor marker in evaluating the infarct size after myocardial infarction but not better than c Tn *** Hs CRP levels were not associated with the severity of CAD but could be useful in the evaluation of myocardial necrosis in patients with STEMI.

关键词： Coronary artery disease High sensitive C-reactive protein Severity