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排序方式: 共有9053条查询结果,搜索用时 210 毫秒
81.
Spatial bound whale optimization algorithm: an efficient high-dimensional feature selection approach
Too Jingwei Mafarja Majdi Mirjalili Seyedali 《Neural computing & applications》2021,33(23):16229-16250
Neural Computing and Applications - Selecting a subset of candidate features is one of the important steps in the data mining process. The ultimate goal of feature selection is to select an optimal... 相似文献
82.
Zamli Kamal Z. Kader Abdul Din Fakhrud Alhadawi Hussam S. 《Neural computing & applications》2021,33(23):16641-16658
Neural Computing and Applications - Cryptography often involves substituting (and converting) the secret information into dummy data so that it could reach the desired destination without leakage.... 相似文献
83.
Kader Md. Abdul Zamli Kamal Z. Ahmed Bestoun S. 《Neural computing & applications》2021,33(23):15933-15953
Neural Computing and Applications - Emperor Penguin Optimizer (EPO) is a recently developed metaheuristic algorithm to solve general optimization problems. The main strength of EPO is twofold.... 相似文献
84.
Zaki Ahmad M. El-Nagar Ahmad M. El-Bardini Mohammad Soliman F. A. S. 《Neural computing & applications》2021,33(5):1515-1531
Neural Computing and Applications - For the current paper, the technique of feed-forward neural network deep learning controller (FFNNDLC) for the nonlinear systems is proposed. The FFNNDLC... 相似文献
85.
Meraj Talha Rauf Hafiz Tayyab Zahoor Saliha Hassan Arslan Lali M. IkramUllah Ali Liaqat Bukhari Syed Ahmad Chan Shoaib Umar 《Neural computing & applications》2021,33(17):10737-10750
Neural Computing and Applications - Lung cancer is a deadly disease if not diagnosed in its early stages. However, early detection of lung cancer is a challenging task due to the shape and size of... 相似文献
86.
Elkenawy Ahmed El-Nagar Ahmad M. El-Bardini Mohammad El-Rabaie Nabila M. 《Neural computing & applications》2021,33(15):9221-9240
Neural Computing and Applications - This study introduces a neural network (NN) adaptive tracking controller-based reinforcement learning (RL) scheme for unknown nonlinear systems. First, an... 相似文献
87.
One of the important aspects in achieving better performance for transient stability assessment (TSA) of power systems employing
computational intelligence (CI) techniques is by incorporating feature reduction techniques. For small power system the number
of features may be small but when larger systems are considered the number of features increased as the size of the systems
increases. Apart from employing faster CI techniques to achieve faster and accurate TSA of power system, feature reduction
techniques are needed in reducing the input features while preserving the needed information so as to make faster training
of the CI technique. This paper presents feature reductions techniques used, namely correlation analysis and principle component
analysis, in reducing number of input features presented to two CI techniques for TSA, namely probabilistic neural network
(PNN) and least squares support vector machines (LS-SVM). The proposed feature reduction techniques are implemented and tested
on the IEEE 39-bus test system and 87-bus Malaysia’s power system. Numerical results are presented to demonstrate the performance
of the feature reduction techniques and its effects on the accuracies and time taken for training the two CI techniques. 相似文献
88.
The paper proposes a new approach to find semantic meanings in visual object class structure, in line with the Gestalt laws
of proximity. Micro level semantic structures are formed by line segments (arcs also approximated into line segments based
on pixel deviation threshold) which are in close proximity. These structures are hierarchically combined till a semantic label
can be assigned. The algorithm extracts semantic groups, their inter-relations and represents these using a graph. Invariant
geometrical properties of the groups and relations are used as vertex and edge labels. A graph model captures the inter class
variability by analyzing the repetitiveness of structures and relations and uses it as a weighting factor for classification.
The algorithm has been tested on a standard benchmark database and compared with existing approaches. 相似文献
89.
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
90.
Mohd Akram Hira Lal Mohammad Osama Farah Ansari Sana Anwar Kabir-ud-Din Ajaz Ahmad Samreen Naved Azum Hadi M. Marwani Abdullah M. Asiri 《Journal of surfactants and detergents》2021,24(1):35-49
In this study, we prepared a novel series of diester-functionalized cationic gemini surfactants (Cm-E2O2-Cm) containing ethylene oxide as a spacer with varying alkyl chain lengths and characterized by 1H NMR, FT-IR, elemental analysis, and ESI-MS. The physicochemical properties of the geminis were explored by tensiometry, fluorescence, dye solubilization, and Krafft point. These geminis acquire superior surface activity than the conventional surfactants. Fluorescence spectroscopy analysis affirmed that the micropolarity and aggregation number of micelles diminished with increase in the alkyl chain length. These geminis represent a new group of amphiphiles of considerably high biodegradability, better cleavability, and low toxicity as assessed by BOD test, FT-IR analysis, and HC50 analysis, respectively. They also showed significant level of antimicrobial activity toward some specified bacterial strains of Gram-positive and Gram-negative by using agar well diffusion method. Furthermore, the thermogravimetric analysis provided information regarding thermal stabilities of the newly synthesized gemini surfactants. 相似文献