检索结果-南通市图书馆

Corporate pledgeable asset ownership and stock price crash risk

在线全文

学校读者我要写书评

暂无评论

Financial Innovation 2022年第1期8卷 855-882页

作者： hail Jung sanghak Choi Junyoup Lee sanggeum Woo school of Management Engineering Ulsan National Institute of Science and TechnologyUNIST-Gil 50Ulsan 44919Republic of Korea school of Business Administration Ulsan National Institute of Science and TechnologyUNIST-Gil 50Ulsan 44919Republic of Korea

We investigate how a firm’s corporate pledgeable asset ownership(CPAO)affects the risk of future stock price *** pledgeable asset ownership and crash risk data for a large sample of ***,we provide novel empirical evidence that a firm’s risk of a future stock price crash decreases with an increase in its pledgeable *** main findings are valid after conducting various robustness *** channel tests reveal that firms with pledgeable assets increase their collateral value,thereby enhancing corporate transparency and limiting bad news hoarding,resulting in lower stock price crash ***,the results show that having more pledgeable assets enables easier access to external financing,making it less likely that managers will hoard bad news.

关键词： Asset pledgeability stock price crash risk Endogeneity tests Information opacity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

用于微裂缝储层描述的一项新技术（二）

国外石油动态 2008年第9期 8-21页

作者： Mohammed s．Ameen Ernest A．hail wood

4 研究区域（Wudayhi气田） 4．1位置和普通地质学 Wudayhi气田（发现于1998年）是一个东一北东走向的背斜构造，长30公里，宽10公里。它位于沙特阿拉伯的东部油区（图5A），拥有构造圈闭和潜在地层圈闭。Wudayhi背斜是由覆盖在断层边... 详细信息

4 研究区域（Wudayhi气田） 4．1位置和普通地质学 Wudayhi气田（发现于1998年）是一个东一北东走向的背斜构造，长30公里，宽10公里。它位于沙特阿拉伯的东部油区（图5A），拥有构造圈闭和潜在地层圈闭。Wudayhi背斜是由覆盖在断层边界基底断块上的古生界一新生界沉积披盖形成的强迫基底卷入褶皱。

关键词：储层描述微裂缝技术背斜构造沙特阿拉伯研究区域东部油区地层圈闭

Mapping of bauxite mineral deposits in the northern region of saudi Arabia by using Advanced spaceborne Thermal Emission and Reflection Radiometer satellite data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geo-spatial Information science 2019年第1期22卷 35-44页

作者： P.sheik Mujabar s.Dajkumar Department of General studies Jubail Industrial CollegeJubailSaudi Arabia Exploration Geoscience PerthAustralia

Mineral deposit mapping is very essential for sustainable and eco-friendly exploitation of natural *** Kingdom of saudi Arabia has abundant natural resources such as natural gas,oil and *** reserves high quantity of minerals such as phosphates,bauxites,copper,gold and other industrial *** red soil regions located in hail and Qassim provinces of saudi Arabia have rich amount of bauxite(major aluminum ore)*** order to initiate the focus on mapping of mineral deposits along this area,standardized hyper-spectral analysis has been carried out by using Advanced spaceborne Thermal Emission and Reflection Radiometer(AsTER)satellite *** spectral signature of gibbsite(major element in bauxite)samples is analyzed with reference to the spectral features of gibbsite in the visible near infrared and short-wave infrared bands electromagnetic *** hyper-spectral transformations such as minimum noise fraction function and pixel purity index have been performed to identify the target *** existence of the mineral is confirmed by comparing the spectral signatures of the endmember with the predefined spectral plots of AsTER and United states Geological survey spectral ***,the end-members are mapped and their abundance is estimated in 0–1 *** study has opened up new areas for mapping of bauxite deposits in the area and leads to eco-friendly exploitation of natural *** also validates the high potential of AsTER multispectral satellite data for the exploration and mapping of mineral resources.

关键词： Mineralogy geology remote sensing saudi Arabia

Generic sensor platform based on electro- responsive molecularly imprinted polymer nanoparticles (e-NanoMIPs)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microsystems & Nanoengineering 2020年第1期6卷 266-274页

作者： A.Garcia-Cruz O.s.Ahmad K.Alanazi E.Piletska s.A.Piletsky school of Chemistry University of LeicesterLeicesterUK

The present research describes the design of robust electrochemical sensors based on electro-responsive molecularly imprinted polymer nanoparticles(e-MIPs).The e-MIPs,tagged with a redox probe,combine both recognition and reporting *** system replaces enzyme-mediator pairs used in traditional *** analyte recognition process relies on the generic actuation phenomenon when the polymer conformation of e-MIPs is changing in response to the presence of the template *** analyte concentration is measured using voltammetric *** an exemplification of this technology,electrochemical sensors were developed for the determination of concentrations of trypsin,glucose,paracetamol,C4-homoserine lactone,and *** present technology allows for the possibility of producing generic,inexpensive,and robust disposable sensors for clinical,environmental,and forensic applications.

关键词： functions. methods. polymer

Influence of magnetic field and Hall currents on blood flow through a stenotic artery

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2008年第8期29卷 1093-1104页

作者： Kh.s.Mekheimer M.A.El Kot Department of Mathematics Faculty of ScienceAl-Azhar University Nasr City 11884CairoEgypt Department of Mathematics Faculty of EducationSuez Canal UniversitySuezEgypt

A micropolar model for blood simulating magnetohydrodynamic flow through a horizontally nonsymmetric but vertically symmetric artery with a mild stenosis is presented. To estimate the effect of the stenosis shape, a suitable geometry has been considered such that the horizontal shape of the stenosis can easily be changed just by varying a parameter referred to as the shape parameter. Flow parameters, such as velocity, the resistance to flow （the resistance impedance）, the wall shear stress distribution in the stenotic region, and its magnitude at the maximum height of the stenosis （stenosis throat）, have been computed for different shape parameters, the Hartmann number and the Hall parameter. This shows that the resistance to flow decreases with the increasing values of the parameter determining the stenosis shape and the hail parameter, while it increases with the increasing Hartmann number. The wall shear stress and the shearing stress on the wall at the maximum height of the stenosis possess an inverse characteristic to the resistance to flow with respect to any given value of the Hartmann number and the Hall parameter. Finally, the effect of the Hartmann number and the Hall parameter on the horizontal velocity is examined.

关键词： stenotic artery Hall currents blood flow

Adaptive Increasing-Order synchronization and Anti-synchronization of Chaotic systems with Uncertain Parameters

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2011年第11期28卷 49-51页

作者： M.Mossa Al-sawalha M.s.M.Noorani Faculty of science Mathematics DepartmentUniversity of HailKingdom of Saudi Arabia Center for Modelling&Data Analysis School of Mathematical SciencesUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia

We elaborate the concept of increasing-order synchronization and anti-synchronization of chaotic systems via an adaptive control scheme and modulation *** is shown that the dynamical evolution of a third-order chaotic system can be synchronized and anti-synchronized with a fourth-order chaotic system even though their parameters are *** analysis and numerical simulations are carried out to verify the results.

关键词： parameters chaotic system

Anti-synchronization of Chaotic systems via Adaptive sliding Mode Control

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2012年第12期29卷 36-38页

作者： Wafaa Jawaada M.s.M.Noorani M.Mossa Al-sawalha school of Mathematical sciences Universiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Faculty of science Mathematics DepartmentUniversity of HailKingdom of Saudi Arabia

An anti-synchronization scheme is proposed to achieve the anti-synchronization behavior between chaotic systems with fully unknown parameters.A sliding surface and an adaptive sliding mode controller are designed to gain the *** stability of the error dynamics is proven theoretically using the Lyapunov stability *** numerical results are presented to justify the theoretical analysis.

关键词： parameters. theory. stability

Microwave-assisted synthesis of Mg:PbI2 nanostructures and their structural,morphological,optical,dielectric and electrical properties for optoelectronic technology

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2020年第11期29卷 420-426页

作者： Mohd.shkir Ziaul Raza Khan T Alshahrani Kamlesh VChandekar M Aslam Manthrammel Ashwani Kumar s AlFaify Advanced Functional Materials and Optoelectronics Laboratory(AFMOL) Department of PhysicsCollege of ScienceKing Khalid UniversityAbha 61413P.O.Box 9004Saudi Arabia Department of Physics College of ScienceUniversity of HailP.O.Box 2440HailSaudi Arabia Department of Physics College of SciencePrincess Nourah Bint Abdulrahman UniversityRiyadh 11671Saudi Arabia Department of Physics Rayat Shikshan Sanstha’sKarmaveer Bhaurao Patil CollegeVashiNavi Mumbai 400703India Department of Physics IK Gujral Punjab Technical UniversityJalandhar 144603India

This work reports the cost-effective growth of Mg:PbI2 nanostructures with 0,1,2.5 and 5.0 wt.%Mg doping ***,vibrational,morphological properties are analyzed using x-ray diffraction(XRD),Raman spectroscopy and scanning electron microscopy(sEM).XRD and Raman studies confirm the monophasic hexagonal system of Mg:PbI2,and no additional impurity peaks are *** scherrer formula is used to determine sizes of crystallites to be in the range of 47-52 ***/sEM e-mapping analyses confirm the incorporation of Mg in PbI2 matrix and its uniform distribution throughout the *** hexagonal nanosheet-and nanoplate-like morphologies are detected in sEM images for pure and Mg-doped *** optical band gap of nanostructures is obtained from Tauc’s relation to be in the range 3.0-3.25 *** and electrical properties are found in significant enhancement as Mg doping in PbI2 matrix,also the conduction mechanism is discussed.

关键词： Mg:PbI2 nanostructures structural properties optical band gap dielectric constant ac conductivity

Observations of NO_2 and O_3 during Thunderstorm Activity Using Visible spectroscopy

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric sciences 1996年第3期13卷 359-374页

作者： D.B.Jadhav A.L.Londhe s.Bose Indian Institute of Tropical Meteorology Dr.Homi Bhabha MargPashanPune-411008MaharashtraIndiaIndian Institute of Tropical MeteorologyDr.Homi Bhabha MargPashanPune-411008MaharashtraIndiaIndian Institute of Tropical MeteorologyDr.Homi Bhabha MargPashanPune-411008MaharashtraIndia

simultaneous observations for the total column densities of NO2,O3 and H2O were carried on using the portable spectrometer (438-450 nm and 400-450 nm) and the visible spectrometer (544.4-628 nm) during premonsoon thunderstorms and embedded hail storm activity at Pune (18°32'N & 73°51'E),*** observations confirm the fact that there is an increase in O3 and NO2 column densities during *** increase in O3 was observed following onset of thunderstorm,while the increase in NO2 was observed only after the thunder flashes *** implies that the production mechanisms for O3 and NO2 in thunderstorm are *** observed column density of NO,value (1 to 3×1017molecules cm-2) during thunderstorm activity is 10 to 30 times higher than the value (1×10th molecules cm-2) of a normal day total column *** spectrometric observations and observations of thunder flashes by electric field meter showed that 6.4×1025molecules/flash of NO2 are *** increased to-oil column density of ozone during thunderstorm period is 1.2 times higher than normal (clear) day ozone *** multiple scattering in the clouds is estimated from H2O and O2 absorption bands in the visible spectral region Considering this effect the calculated amount of ozone added in the global atmosphere due to thunderstorm activity is 0.26 to 0 52 DU,and the annual production of ozone due to thunderstorm activity is of the order of 4.02×10 molecules/year The annual NO2 production may be of the order of 2.02×1035molecules/year.

关键词： Visible spectroscopy Thunderstorm Ozone production NO2 production Atmospheric electricity Lightning flashes. Multiple scattering factor