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1.
Bushra Bashir Muhammad Usman Khalid Muhammad Aadil Sonia Zulfiqar Muhammad Farooq Warsi Philips O. Agboola Imran Shakir 《Ceramics International》2021,47(3):3603-3613
NiO nanostructure was synthesized using a simple co-precipitation method and was embedded on reduced graphene oxide surface via ultrasonication. Structural investigations were made through X-ray diffraction (XRD) and functional groups were confirmed by Fourier transform infrared spectroscopy (FTIR). XRD analysis revealed the grain size reduction with doping. Fourier transform infrared spectroscopy confirmed the presence of metal-oxygen bond in pristine and doped NiO nanostructure as well as the presence of carbon containing groups. Scanning electron microscopy (SEM) indicated that the particle size decreased when NiO nanostructure was doped with copper. BET surface area was found to increase almost up to 43 m2/g for Cu doped NiO nanostructure/rGO composite. Current-voltage measurements were performed using two probe method. UV–Visible spectroscopic profiles showed the blue and red shift for Cu doped NiO nanostructure and Cu doped NiO Nanostructure/rGO composite respectively. Rate constant for Cu doped NiO nanostructure/rGO composite found to increase 4.4 times than pristine NiO nanostructure. 相似文献
2.
Susan Sabra Khalid Mahmood Malik Muhammad Afzal Vian Sabeeh Ahmad Charaf Eddine 《Expert Systems》2020,37(1):e12388
Clinical narratives such as progress summaries, lab reports, surgical reports, and other narrative texts contain key biomarkers about a patient's health. Evidence-based preventive medicine needs accurate semantic and sentiment analysis to extract and classify medical features as the input to appropriate machine learning classifiers. However, the traditional approach of using single classifiers is limited by the need for dimensionality reduction techniques, statistical feature correlation, a faster learning rate, and the lack of consideration of the semantic relations among features. Hence, extracting semantic and sentiment-based features from clinical text and combining multiple classifiers to create an ensemble intelligent system overcomes many limitations and provides a more robust prediction outcome. The selection of an appropriate approach and its interparameter dependency becomes key for the success of the ensemble method. This paper proposes a hybrid knowledge and ensemble learning framework for prediction of venous thromboembolism (VTE) diagnosis consisting of the following components: a VTE ontology, semantic extraction and sentiment assessment of risk factor framework, and an ensemble classifier. Therefore, a component-based analysis approach was adopted for evaluation using a data set of 250 clinical narratives where knowledge and ensemble achieved the following results with and without semantic extraction and sentiment assessment of risk factor, respectively: a precision of 81.8% and 62.9%, a recall of 81.8% and 57.6%, an F measure of 81.8% and 53.8%, and a receiving operating characteristic of 80.1% and 58.5% in identifying cases of VTE. 相似文献
3.
Molecular structure and granule morphology of native and heat‐moisture‐treated pinhão starch
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Vania Z. Pinto Khalid Moomand Nathan L. Vanier Rosana Colussi Franciene A. Villanova Elessandra R. Zavareze Loong‐Tak Lim Alvaro R. G. Dias 《International Journal of Food Science & Technology》2015,50(2):282-289
Pinhão seed is an unconventional source of starch and the pines grow up in native forests of southern Latin America. In this study, pinhão starch was adjusted at 15, 20 and 25% moisture content and heated to 100, 110 and 120 °C for 1 h. A decrease in λ max (starch/iodine complex) was observed as a result of increase in temperature and moisture content of HMT. The ratio of crystalline to amorphous phase in pinhão starch was determined via Fourier transform infra red by taking 1045/1022 band ratio. A decrease in crystallinity occurred as a result of HMT. Polarised light microscopy indicated a loss of birefringence of starch granules under 120 °C at 25% moisture content. Granule size distribution was further confirmed via scanning electron microscopy which showed the HMT effects. These results increased the understanding on molecular and structural properties of HMT pinhão starch and broadened its food and nonfood industrial applications. 相似文献
4.
Enas Taha Sayed Hussain Alawadhi A.G. Olabi Aisha Jamal Menna Salah Almahdi Juiaria Khalid Mohammad Ali Abdelkareem 《International Journal of Hydrogen Energy》2021,46(8):5975-5983
Microbial fuel cell (MFC) is a promising technology for simultaneous wastewater treatment and energy harvesting. The properties of the anode material play a critical role in the performance of the MFC. In this study, graphene oxide was prepared by a modified hummer's method. A thin layer of graphene oxide was incorporated on the carbon brush using an electrophoretic technique. The deoxygenated graphene oxide formed on the surface of the carbon brush (RGO-CB) was investigated as a bio-anode in MFC operated with real wastewater. The performance of the MFC using the RGO-CB was compared with that using plain carbon brush anode (PCB). Results showed that electrophoretic deposition of graphene oxide on the surface of carbon brush significantly enhanced the performance of the MFC, where the power density increased more than 10 times (from 33 mWm?2 to 381 mWm?2). Although the COD removal was nearly similar for the two MFCs, i.e., with PCB and RGO-CB; the columbic efficiency significantly increased in the case of RGO-CB anode. The improved performance in the case of the modified electrode was related to the role of the graphene in improving the electron transfer from the microorganism to the anode surface, as confirmed from the electrochemical impedance spectroscopy measurements. 相似文献
5.
Khalid Tauqeer Khan Abdul Nasir Ali Mazhar Adeel Adil ur Rehman Khan Atta Shuja Junaid 《Multimedia Tools and Applications》2019,78(17):24595-24615
Multimedia Tools and Applications - The world is facing many problems including that of traffic congestion. To highlight the issue of traffic congestion worldwide specially in urban areas and to... 相似文献
6.
Bulge is a defect that causes geometrical inaccuracy and premature failure in the innovative incremental sheet forming (ISF) process. This study has two-fold objectives: (1) knowing the bulging behavior of a Cu clad tri-layered steel sheet as a function of forming conditions, and (2) analyzing the bending effect on bulging in an attempt to identify the associated mechanism. A series of ISF tests and bending analysis are performed to realize these objectives. From the cause-effect analysis, it is found that bulge formation in the layered sheet is sensitive to forming conditions in a way that bulging can be minimized utilizing annealed material and performing ISF with larger tool diameter and step size. The bending under tension analysis reveals that the formation of bulge is an outgrowth of bending moment that the forming tool applies on the sheet during ISF. Furthermore, the magnitude of bending moment depending upon the forming conditions varies from 0.046 to 10.24 N·m/m and causes a corresponding change in the mean bulge height from 0.07 to 0.91 mm. The bending moment governs bulging in layered sheet through a linear law. These findings lead to a conclusion that the bulge defect can be overcome by controlling the bending moment and the formula proposed can be helpful in this regards. 相似文献
7.
Anmar W. Sabri Zainab H. Ali Serwan F. Shawkat Lamia A. Thejar Thaer I. Kassim Khalid A. Rasheed 《河流研究与利用》1993,8(3):237-250
The influences of the Samarra impoundment on the ecology of the downstream sector of the river Tigris are investigated. Zooplankton were collected monthly from July 1987 to July 1988. It was found that zooplankton were most abundant during high river discharges in March. During the month of low river discharge, September, the zooplankton population was greatly reduced immediately below the barrage and remained so to the last downstream station. Several factors seem to explain such differences. The high discharge from the impoundment was found to be the dominating factor and may flush the small backwaters in which zooplankton were abundant, thus increasing the population in the river. Zooplankton species vary in their ability to sustain populations in the river, variations which are due mainly to species-specific characteristics. 相似文献
8.
Khalid Mahmood Zia Mehdi Barikani Ijaz Ahmad Bhatti Mohammad Zuber Haq Nawaz Bhatti 《应用聚合物科学杂志》2008,109(3):1840-1849
A series of polyurethane (PU) elastomers was prepared by the reaction of poly(?‐caprolactone) and 4,4′‐diphenylmethane diisocyanate, which was extended with a series of chain extenders (CEs) having 2–10 methylene units in their structure. The completion of the reaction was confirmed by Fourier transform infrared spectroscopy. The chemical structures of the synthesized PU samples were characterized with Fourier transform infrared, 1H‐NMR, and 13C‐NMR spectroscopy, and the thermal properties were determined by thermogravimetric analysis, DSC, and dynamic mechanical thermal analysis techniques. The mechanical properties were also studied and are discussed. The thermogravimetric analysis and DSC analysis showed that CE length had a considerable effect on the thermal properties of the prepared samples. The dynamic mechanical thermal analysis and damping peaks were also affected by the number of methylene units in the CE length. The elastomer extended with 1,2‐ethane diol exhibited optimum thermal properties, whereas the elastomer based on 1,10‐decane diol displayed the worst thermal properties. Tensile strength and elongation at break decreased with increasing CE length, whereas hardness showed the opposite trend. The glass‐transition temperature moved toward lower temperatures with increasing CE length. The decrease in the glass‐transition temperature and tensile properties were interpreted in terms of decreasing hard segments and increasing chain flexibility. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
9.
Khalid KASSARA 《控制理论与应用(英文版)》2012,10(3):303-308
The aim of this paper is to propose a new way to deal with observability of systems governed by ODEs, in a more general setting than the standard output equation.The primary finding is that observability over a time horizon reduces to single-valuedness of the vertical section of a set we name the observability kernel.The latter consists of the viability kernel of the output domain under the augmented system.The approach may be used either for global or local observability,to which available results on single-valuedness of multifunctions shall be applied in order to get necessary and/or sufficient characterizing conditions.Several examples are provided in order to illustrate the method. 相似文献
10.
Autonomous mapping of HL7 RIM and relational database schema 总被引:1,自引:0,他引:1
Shagufta Umer Muhammad Afzal Maqbool Hussain Khalid Latif Hafiz Farooq Ahmad 《Information Systems Frontiers》2012,14(1):5-18
Healthcare systems need to share information within and across the boundaries in order to provide better care to the patients.
For this purpose, they take advantage of the full potential of current state of the art in healthcare standards providing
interoperable solutions. HL7 V3 specification is an international message exchange and interoperability standard. HL7 V3 messages
exchanged between healthcare applications are ultimately recorded into local healthcare databases, mostly in relational databases.
In order to bring these relational databases in compliance with HL7, mappings between HL7 RIM (Reference Information Model)
and relational database schema are required. Currently, RIM and database mapping is largely performed manually, therefore
it is tedious, time consuming, error prone and expensive process. It is a challenging task to determine all correspondences
between RIM and schema automatically because of extreme heterogeneity issues in healthcare databases. To reduce the amount
of manual efforts as much as possible, autonomous mapping approaches are required. This paper proposes a technique that addresses
the aforementioned mapping issue and aligns healthcare databases to HL7 V3 RIM specifications. Furthermore, the proposed technique
has been implemented as a working application and tested on real world healthcare systems. The application loads the target
healthcare schema and then identifies the most appropriate match for tables and the associated fields in the schema by using
domain knowledge and the matching rules defined in the Mapping Knowledge Repository. These rules are designed to handle the
complexity of semantics found in healthcare databases. The GUI allows users to view and edit/re-map the correspondences. Once
all the mappings are defined, the application generates Mapping Specification, which contains all the mapping information
i.e. database tables and fields with associated RIM classes and attributes. In order to enable the transactions, the application
is facilitated with the autonomous code generation from the Mapping Specification. The Code Generator component focuses primarily
on generating custom classes and hibernate mapping files against the runtime system to retrieve and parse the data from the
data source—thus allows bi-directional HL7 to database communication, with minimum programming required. Our experimental
results show 35–65% accuracy on real laboratory systems, thus demonstrating the promise of the approach. The proposed scheme
is an effective step in bringing the clinical databases in compliance with RIM, providing ease and flexibility. 相似文献