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991.
General competence trust among supply chain partners, referring to the trust that a partner holds the general ability of fulfilling contracts, is a critical factor to ensure effective cooperation in a supply chain, especially in the current financial crisis. The method of supply chain trust diagnosis (SCTD) is to evaluate whether or not a partner holds such competence. This research devotes to an early investigation on diagnosing competence trust of supply chain with the method of inductive case-based reasoning ensemble (ICBRE). The so-called supply chain trust diagnosis with inductive case-based reasoning ensemble consists of five levels, that is, information level, the level of ratios of general competence states, the level of inductive case-based reasoning, ensemble level, and diagnosis result level. Knowledge for diagnosing competence trust, which composes of a case base, is hidden in data represented by ratios of general competence states. Inductive approach is combined with randomness to construct diverse and good member methods of inductive case-based reasoning. Finally, simple voting is used to integrate outputs of member inductive case-based reasoning methods in order to produce the final diagnosis on whether or not a partner holds the general ability of fulfilling contracts. We statistically validated results of the method of supply chain trust diagnosis with inductive case-based reasoning ensemble by comparing them with those of multivariate discriminant analysis, logistic regression, single Euclidean case-based reasoning, and single inductive case-based reasoning. The results indicate that the method of supply chain trust diagnosis with inductive case-based reasoning ensemble significantly improves predictive capability of case-based reasoning in this problem and outperforms all the comparative models by group decision of several decision-making agents and non-strict assumptions like statistical methods. 相似文献
992.
This paper presents a short term load forecasting model based on Bayesian neural network (shorted as BNN) learned by the Hybrid Monte Carlo (shorted as HMC) algorithm. The weight vector parameter of the Bayesian neural network is a multi-dimensional random variable. In learning process, the Bayesian neural network is considered as a special Hamiltonian dynamical system, and the weights vector as the system position variable. The HMC algorithm is used to learn the weight vector parameter with respect to Normal prior distribution and Cauchy prior distribution, respectively. The Bayesian neural networks learned by Laplace algorithm and HMC algorithm and the artificial neural network (ANN) learned by the BP algorithm were used to forecast the hourly load of 25 days of April (Spring), August (Summer), October (Autumn) and January (Winter), respectively. The roots mean squared error (RMSE) and the mean absolute percent errors (MAPE) were used to measured the forecasting performance. The experimental result shows that the BNNs learned by HMC algorithm have far better performance than the BNN learned by Laplace algorithm and the neural network learned BP algorithm and the BNN learned by HMC has powerful generalizing capability, it can welly solve the overfitting problem. 相似文献
993.
Qishi Wu Mengxia Zhu Yi Gu Patrick Brown Xukang Lu Wuyin Lin Yangang Liu 《Journal of Grid Computing》2012,10(3):367-393
Next-generation scientific applications feature complex workflows comprised of many computing modules with intricate inter-module dependencies. Supporting such scientific workflows in wide-area networks especially Grids and optimizing their performance are crucial to the success of collaborative scientific discovery. We develop a Scientific Workflow Automation and Management Platform (SWAMP), which enables scientists to conveniently assemble, execute, monitor, control, and steer computing workflows in distributed environments via a unified web-based user interface. The SWAMP architecture is built entirely on a seamless composition of web services: the functionalities of its own are provided and its interactions with other tools or systems are enabled through web services for easy access over standard Internet protocols while being independent of different platforms and programming languages. SWAMP also incorporates a class of efficient workflow mapping schemes to achieve optimal end-to-end performance based on rigorous performance modeling and algorithm design. The performance superiority of SWAMP over existing workflow mapping schemes is justified by extensive simulations, and the system efficacy is illustrated by large-scale experiments on real-life scientific workflows for climate modeling through effective system implementation, deployment, and testing on the Open Science Grid. 相似文献
994.
Yong Song Yi-bin Li Cai-hong Li Gui-fang Zhang 《International Journal of Control, Automation and Systems》2012,10(1):166-172
This article demonstrates that Q-learning can be accelerated by appropriately specifying initial Q-values using dynamic wave
expansion neural network. In our method, the neural network has the same topography as robot work space. Each neuron corresponds
to a certain discrete state. Every neuron of the network will reach an equilibrium state according to the initial environment
information. The activity of the special neuron denotes the maximum cumulative reward by following the optimal policy from
the corresponding state when the network is stable. Then the initial Q-values are defined as the immediate reward plus the
maximum cumulative reward by following the optimal policy beginning at the succeeding state. In this way, we create a mapping
between the known environment information and the initial values of Q-table based on neural network. The prior knowledge can
be incorporated into the learning system, and give robots a better learning foundation. Results of experiments in a grid world
problem show that neural network-based Q-learning enables a robot to acquire an optimal policy with better learning performance
compared to conventional Q-learning and potential field-based Qlearning. 相似文献
995.
The research of adaptive sliding mode controller for motor servo system using fuzzy upper bound on disturbances 总被引:1,自引:0,他引:1
Xiaodong Liu Yunjie Wu Baiting Liu 《International Journal of Control, Automation and Systems》2012,10(5):1064-1069
Considering sliding mode control (SMC) method using the estimation of upper bound on disturbances in motor servo system, if the upper bound is underestimated, the position tracking precision is poor. Contrarily, the control input is overlarge and even chatters violently. To solve the above problems, an adaptive sliding mode controller (ASMC) is proposed. It utilizes a fuzzy decision maker (FDM), which exports the estimation of upper bound on disturbances according to the information of position tracking error and control input. The computer simulations on a dc motor present that the proposed method guarantees satisfactory position tracking accuracy and the chattering at control input is evidently suppressed. Moreover, the output of FDM is sensitive to the changes of disturbances realtimely and precisely. Subsequently, the proposed scheme possesses strong robust performance against disturbances in motor servo system. 相似文献
996.
Alejandro F. Villaverde Cesáreo Raimúndez Antonio Barreiro 《International Journal of Control, Automation and Systems》2012,10(1):78-87
Crane operation is a challenging task, due to the combined problem of obstacle avoidance and load swing suppression in underactuated
conditions. This paper presents a human-machine interface that increases the operator’s perception of a gantry crane’s workspace.
With this aim, a virtual environment resembling the workspace is connected with a haptic device. This allows the user to receive
not only visual but also tactile feedback, thus increasing maneuvering safety. Additionally, this capability is integrated
in a teleoperation setup, adopting a passivity-based control approach that guarantees overall stability. This includes also
the design of controllers by means of the IDA-PBC method. Experimental results carried out with a laboratory crane show its
feasibility for internet-based teleoperation and demonstrate the improvements on the system performance. 相似文献
997.
Kazunori Sakurama Kazushi Nakano 《International Journal of Control, Automation and Systems》2012,10(1):50-60
This paper addresses a path tracking problem with obstacle avoidance for Lagrange systems. The proposed method is based on
field potential methods in combination with navigation functions for obstacle avoidance. First, it is shown that a simple
combination of the navigation function with the conventional path tracking controller does not work. Therefore, in order to
cope with this problem, a new feedback law is proposed for a path parameter which characterizes the reference path. It is
proved that the proposed controller achieves both path following and collision avoidance. Moreover, since the method adopts
bounded navigation functions, the proposed controllers generate bounded input signals even when target systems approach obstacles.
Finally, an experimental evaluation is performed with a two-link manipulator to illustrate the effectiveness of the proposed
method. 相似文献
998.
Insulator-based dielectrophoresis (iDEP) has been successfully used for on-chip manipulations of biological samples. Despite
its effectiveness, iDEP typically requires high DC voltages to achieve sufficient electric field; this is mainly due to the
coupled phenomena among linear electrokinetics: electroosmosis (EO) and electrophoresis (EP) and nonlinear electrokinetics:
dielectrophoresis (DEP). This paper presents a microfluidic technique using DC-offset AC electric field for electrokinetic
concentration of particles and cells by repulsive iDEP. This technique introduces AC electric field for producing iDEP which
is decoupled from electroosmosis (EO) and electrophoresis (EP). The repulsive iDEP is generated in a PDMS tapered contraction
channel that induces non-uniform electric field. The benefits of introducing AC electric field component are threefold: (i)
it contributes to DEP force acting on particles, (ii) it suppresses EO flow and (iii) it does not cause any EP motion. As
a result, the required DC field component that is mainly used to transport particles on the basis of EO and EP can be significantly
reduced. Experimental results supported by numerical simulations showed that the total DC-offset AC electric field strength
required to concentrate 15-μm particles is significantly reduced up to 85.9% as compared to using sole DC electric field.
Parametric experimental studies showed that the higher buffer concentration, larger particle size and higher ratio of AC-to-DC
electric field are favorable for particle concentration. In addition, the proposed technique was demonstrated for concentration
of yeast cells. 相似文献
999.
We present a deposited microbead plug (DMBP)-based microfluidic chip capable of performing plasma extraction and on-chip immunoassay.
The DMBP used as a porous blood filter provides pure blood plasma without the contamination of blood cells or beads. Capillary-driven
flow eliminates the requirement of external pumps. The human IgG and goat anti-human IgG sample-to-answer assay was performed
in this chip within 600 s using only a 10 μl whole-blood sample. This easy-to-use, rapid, inexpensive, and disposable DMBP-based
chip holds a great promise for point-of-care application. 相似文献
1000.
Ming Li Shunbo Li Jinbo Wu Weijia Wen Weihua Li Gursel Alici 《Microfluidics and nanofluidics》2012,12(5):751-760
We report a simple and cost-effective method for fabricating integrated electronic-microfluidic devices with multilayer configurations.
A CO2 laser plotter was employed to directly write patterns on a transferred polydimethylsiloxane (PDMS) layer, which served as
both a bonding and a working layer. The integration of electronics in microfluidic devices was achieved by an alignment bonding
of top and bottom electrode-patterned substrates fabricated with conventional lithography, sputtering and lift-off techniques.
Processes of the developed fabrication method were illustrated. Major issues associated with this method as PDMS surface treatment
and characterization, thickness-control of the transferred PDMS layer, and laser parameters optimization were discussed, along
with the examination and testing of bonding with two representative materials (glass and silicon). The capability of this
method was further demonstrated by fabricating a microfluidic chip with sputter-coated electrodes on the top and bottom substrates.
The device functioning as a microparticle focusing and trapping chip was experimentally verified. It is confirmed that the
proposed method has many advantages, including simple and fast fabrication process, low cost, easy integration of electronics,
strong bonding strength, chemical and biological compatibility, etc. 相似文献