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11.
G. A. Tul'chinskii Bui Tkhyk Khet 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1991,25(6):364-367
1. | The equipment of the Hoabinh hydroelectric plant operates in conformity with the specified parameters and ensures utilization of the installed capacity in the power system of North Vietnam. Further increase in the effectiveness of utilization of the plant capacity and of its specific share in the base portion of the load graph are determined by development of the transmission line system for supply to the consumers and the interconnection with the power system of central Vietnam. |
2. | As a result of the investigations and the introduced measures for realization of the multistage personnel training system, safe and accident-free operation has been ensured for operation of the first units under conditions of combination with construction-erection work in the underground complex of the hydroelectric plant. |
12.
Engineering with Computers - This paper is devoted to numerical investigations on mechanical behavior of cracked composite functionally graded (FG) plates. We thus develop an efficient adaptive... 相似文献
13.
Jeanne Volatron Florent Carn Jelena Kolosnjaj‐Tabi Yasir Javed Quoc Lam Vuong Yves Gossuin Christine Ménager Nathalie Luciani Gaëlle Charron Miryana Hémadi Damien Alloyeau Florence Gazeau 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(2)
Proteins implicated in iron homeostasis are assumed to be also involved in the cellular processing of iron oxide nanoparticles. In this work, the role of an endogenous iron storage protein—namely the ferritin—is examined in the remediation and biodegradation of magnetic iron oxide nanoparticles. Previous in vivo studies suggest the intracellular transfer of the iron ions released during the degradation of nanoparticles to endogenous protein cages within lysosomal compartments. Here, the capacity of ferritin cages to accommodate and store the degradation products of nanoparticles is investigated in vitro in the physiological acidic environment of the lysosomes. Moreover, it is questioned whether ferritin proteins can play an active role in the degradation of the nanoparticles. The magnetic, colloidal, and structural follow‐up of iron oxide nanoparticles and proteins in lysosome‐like medium confirms the efficient remediation of potentially harmful iron ions generated by nanoparticles within ferritins. The presence of ferritins, however, delays the degradation of particles due to a complex colloidal behavior of the mixture in acidic medium. This study exemplifies the important implications of intracellular proteins in processes of degradation and metabolization of iron oxide nanoparticles. 相似文献
14.
Bruno H. G. Barbosa Lam T. Bui Hussein A. Abbass Luis A. Aguirre Ant?nio P. Braga 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2011,15(9):1735-1747
This paper presents two new approaches for constructing an ensemble of neural networks (NN) using coevolution and the artificial
immune system (AIS). These approaches are extensions of the CLONal Selection Algorithm for building ENSembles (CLONENS) algorithm.
An explicit diversity promotion technique was added to CLONENS and a novel coevolutionary approach to build neural ensembles
is introduced, whereby two populations representing the gates and the individual NN are coevolved. The former population is
responsible for defining the ensemble size and selecting the members of the ensemble. This population is evolved using the
differential evolution algorithm. The latter population supplies the best individuals for building the ensemble, which is
evolved by AIS. Results show that it is possible to automatically define the ensemble size being also possible to find smaller
ensembles with good generalization performance on the tested benchmark regression problems. More interestingly, the use of
the diversity measure during the evolutionary process did not necessarily improve generalization. In this case, diverse ensembles
may be found using only implicit diversity promotion techniques. 相似文献
15.
Towards a web-based progressive handwriting recognition environment for mathematical problem solving
The emergence of pen-based mobile devices such as PDAs and tablet PCs provides a new way to input mathematical expressions to computer by using handwriting which is much more natural and efficient for entering mathematics. This paper proposes a web-based handwriting mathematics system, called WebMath, for supporting mathematical problem solving. The proposed WebMath system is based on client–server architecture. It comprises four major components: a standard web server, handwriting mathematical expression editor, computation engine and web browser with Ajax-based communicator. The handwriting mathematical expression editor adopts a progressive recognition approach for dynamic recognition of handwritten mathematical expressions. The computation engine supports mathematical functions such as algebraic simplification and factorization, and integration and differentiation. The web browser provides a user-friendly interface for accessing the system using advanced Ajax-based communication. In this paper, we describe the different components of the WebMath system and its performance analysis. 相似文献
16.
17.
C. Bui Thanh H. Klaudel F. Pommereau 《Electronic Notes in Theoretical Computer Science》2003,68(5):85-100
We present a new approach to the modelling of time constrained systems. It is based on untimed high-level Petri nets using the concept of causal time. With this concept, the progression of time is modelled in the system by the occurrence of a distinguished event, tick, which serves as a reference to the rest of the system. In order to validate this approach as suitable for automated verification, a case study is provided and the results obtained using a model-checker on high-level Petri nets are compared with those obtained for timed automata using prominent tools. The comparison is encouraging and shows that the causal time approach is intuitive and modular. It also potentially allows for efficient verification. 相似文献
18.
Tiantang Yu Tinh Quoc Bui Peng Liu Sohichi Hirose 《International Journal of Mechanics and Materials in Design》2016,12(1):85-107
In this work, a new approach in the framework of the local partition of unity finite element method (XFEM) to significantly improve the accuracy of natural frequency in free vibration analysis of cracked Reissner–Mindlin plates is presented. Different from previous approaches, the present formulation is expected to be more accurate and effective in modeling cracked plates by integrating the stabilized discrete shear gap (DSG) into the XFEM setting. Intensive numerical results at low frequency demonstrated that the novel DSG-based XFEM approach possesses the following desirable properties: (1) the awkwardness of transverse shear-locking phenomenon can be overcome easily; (2) the DSG-based XFEM can be applicable to both moderately thick and thin plates straightforwardly; (3) the representation of cracks is independent of finite element mesh; (4) mesh distortion is insensitive and controllable; (5) the accuracy of natural frequency obtained by the present method is high and (6) the present method uses three-node triangular elements that can be much easily generated automatically for problems even with complicated geometry. These properties of the DSG-based XFEM are confirmed through several numerical examples of cracked plates with different boundary conditions. 相似文献
19.
Chen T.-h. Chang K.W. Bui S.B. Wang H. Dow G.S. Liu L.C.T. Lin T.S. Titus W.S. 《Microwave Theory and Techniques》1991,39(12):1980-1986
The design and fabrication of four broadband monolithic passive baluns including CPW Marchand, multilayer MS Marchand, planar-transformer and broadside-coupled line baluns are presented. Operational frequencies range from 1.5 GHz to 24 GHz. Maximum relative bandwidths in excess of 3:1 are achieved. Simulated performances using full wave electromagnetic analysis are shown to agree with the measured results. Two accurate equivalent circuit models constructed from either electromagnetic simulated or measured S-parameters are developed for the MS Marchand and transformer baluns making the optimization of baluns and circuit design using the baluns much more efficient. The design of monolithic double-balanced diode mixer using two planar-transformer baluns is also presented. Without DC bias, the mixer shows a minimum conversion loss of 6 dB with the RF at 5 GHz and a LO drive of 15 dBm at 4 GHz. The measured input IP3 of this mixer is better than 15 dBm over the 4 to 5.75 GHz frequency band 相似文献
20.
Bulk ultrafine-grained nickel specimens having grain sizes in the range of 0.25-5 μm were consolidated by hot isostatic pressing technique. The resulting microstructures were characterized by transmission electron microscopy and X-ray diffraction analysis. Compression tests were carried out at room temperature and at strain rate of 1.6×10−4 s−1. It was found that the measured yield strength does not follow the Hall-Petch law as a consequence of the presence of oxide phase. Therefore, the use of micromechanics based model, which takes into account only the Hall-Petch relationship at grain level for predicting the grain sized effects on mechanical behavior of this kind of materials, is not accurate yet. In this study, a modification made to the generalized self-consistent model was proposed for studying both grain size and oxide phase dependence of ultrafine-grained materials behavior. Because of the novel modification, an optimization procedure with two steps was required to identify the parameters of micromechanical model. An acceptable agreement between experimental and numerical results was achieved. Moreover, the influence of texture on the yield strength and the application of the proposed model to the spark plasma sintering processed materials were also discussed. 相似文献