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141.
Scanning laser range sensors provide range data consisting of a set of point measurements. The laser sensor URG-04LX has a
distance range of approximately 0.02–4 m and a scanning angle range of 240°. Usually, such an image range is acquired from
one viewpoint by “moving” the laser beam using rotating mirrors/prisms. The orientation of the laser beam can easily be measured
and converted into the coordinates of the image. This article conducts localization using virtual labels with data about distances
in the environment obtained from 2D distance laser sensors. This method puts virtual labels on special features and points
which are along the mobile robot’s path. The current location is calculated by combining the virtual label and the range image
of the laser range finder. 相似文献
142.
Maintaining integrity and consistency, and effecting conformance in architectures of large-scale systems require specification and enforcement of many different forms of structural constraints. While type systems have proved effective for enforcing structural constraints in programs and data structures, most architectural modeling frameworks include only weak notions of typing or rely on first order logic constraint languages that have steep learning curves associated with them and that become unwieldy when scaling to large systems.We present the Cadena Architecture Language with Meta-modeling (CALM) — that uses multi-level type systems to specify and enforce a variety of architectural constraints relevant to the development of large-scale component-based systems. Cadena is a robust and extensible tool that has been used to specify a number of industrial strength component models and applied in multiple industrial research projects on model-driven development and software product lines. 相似文献
143.
Tomoko Watanabe Traphagan Yueh-hui Vanessa Chiang Hyeseung Maria Chang Benjaporn Wattanawaha Haekyung Lee Michael Charles Mayrath Jeongwon Woo Hyo-Jin Yoon Min Jung Jee Paul E. Resta 《Computers & Education》2010
Using a framework of cognitive, social, and teaching presence, the nature of learning experiences in a three-dimensional virtual world environment (Second Life) and a text-chat learning environment without visuals (TeachNet) were investigated. A mixed method of code frequencies, coherence graphs, interviews, and a survey was used. The results revealed that the TeachNet debates included more cognitive presence codes that indicate higher levels of cognitive processing than in SL debates. The teams were significantly different from each other in the collaboration style for developing arguments and in the ways to use utterances associated with cognitive, social, and teaching presences, and the groups’ collaboration style became more established with more experience with the tasks. The three critical factors–tool, tasks and group cohesion–that affect cognitive, teaching, and social presence are discussed. 相似文献
144.
In-Ho Jung 《Calphad》2010
Computerized thermodynamic databases for solid and liquid steel, slags and solid oxide solutions, for large numbers of components, have been developed over the last three decades by critical evaluation/optimization of all available phase equilibrium and thermodynamic data. The databases contain model parameters specifically developed for molten slags, liquid and solid steel and solid oxide solutions. With user-friendly software, which accesses these databases, complex chemical reactions and phase equilibria occurring throughout the steelmaking process can be calculated over wide ranges of temperature, oxygen potential and pressure. In the present article, the thermodynamic models and databases for molten slag and liquid steel included in well-known thermochemical packages and their applications to complex steelmaking processes involving molten slag, steel, inclusions, refractories and gases are reviewed. 相似文献
145.
The purpose of this study is twofold: first, to investigate user goals in social virtual worlds; second, to introduce a methodological alternative (i.e., a means-end chain approach) for analyzing user goals in cyberspaces. The data were acquired from a web survey, and were analyzed by means-end chain analysis (MECA), which produces users’ goal structure in reference to a hierarchical system of interrelated goals (Olson & Reynolds, 1983). The results show that people come to social virtual worlds to satisfy their social and hedonic needs, and to escape from real world constraints, as do virtual community members and virtual gamers; they also pursue unique activities, such as creating virtual objects and selling them. On the other hand, by clarifying relations among users’ goals, MECA provides a richer explanation for user goals than prior research which only offers separate user goals for cyberspace users without explanation of relationship among goals. 相似文献
146.
147.
Yao Jung Yang Tien-Wen Sung Chuni Wu Hsiang-Yang Chen 《Expert systems with applications》2010,37(1):393-400
The paper describes what we have learned from implementing a multi-agent architecture used to support enterprise notions and principles for intelligent systems design. In the last couple of years, agent-based management systems have been widely used to monitor and control business design processes. In this paper, multi-agent architecture is proposed and applied to the workflow management system in ASE1 (Advance Semiconductor Electronic) Inc., which is the world’s well-known largest provider of independent semiconductor for manufacturing services in assembly and test. The proposed FIPA-OS autonomous workflow management system uses a workflow co-ordination mechanism and an agent integration mechanism to enable the routine daily jobs error handle. Our vision for extending the FIPA-OS architectural elements to cover the development and implementation of generic web-Centric collaborative applications concludes the paper. 相似文献
148.
Jung Jin Cho Yu Ding Yong Chen Jiong Tang 《Automation Science and Engineering, IEEE Transactions on》2010,7(1):81-95
This paper presents a robust calibration procedure for clustered wireless sensor networks. Accurate calibration of between-node distances is one crucial step in localizing sensor nodes in an ad-hoc sensor network. The calibration problem is formulated as a parameter estimation problem using a linear calibration model. For reducing or eliminating the unwanted influence of measurement corruptions or outliers on parameter estimation, which may be caused by sensor or communication failures, a robust regression estimator such as the least-trimmed squares (LTS) estimator is a natural choice. Despite the availability of the FAST-LTS routine in several statistical packages (e.g., R, S-PLUS, SAS), applying it to the sensor network calibration is not a simple task. To use the FAST-LTS, one needs to input a trimming parameter, which is a function of the sensor redundancy in a network. Computing the redundancy degree and subsequently solving the LTS estimation both turn out to be computationally demanding. Our research aims at utilizing some cluster structure in a network configuration in order to do robust estimation more efficiently. We present two algorithms that compute the exact value and a lower bound of the redundancy degree, respectively, and an algorithm that computes the LTS estimation. Two examples are presented to illustrate how the proposed methods help alleviate the computational demands associated with robust estimation and thus facilitate robust calibration in a sensor network. 相似文献
149.
Position control of a mobile inverted pendulum system using radial basis function network 总被引:2,自引:0,他引:2
Jin Seok Noh Geun Hyung Lee Seul Jung 《International Journal of Control, Automation and Systems》2010,8(1):157-162
This article presents the implementation of position control of a mobile inverted pendulum (MIP) system by using the radial
basis function (RBF) network. The MIP has two wheels to move on the plane and to balance the pendulum. The MIP is a nonlinear
system whose dynamics is nonholonomic. The goal of this study was to control the MIP to maintain the balance of the pendulum
while tracking a desired position of the cart. The reference compensation technique scheme is used as a neural network control
method for the MIP. The back-propagation learning algorithm of the RBF network is derived for online learning and control.
The control algorithm has been embedded on a DSP 2812 board to achieve real-time control. Experimental results are conducted
and show successful control performances of both balancing and tracking the desired position of the MIP. 相似文献
150.
Palanisamy GomathiAuthor VitaeMin Kwan KimAuthor Vitae Jung Je ParkAuthor VitaeDhanusuraman RagupathyAuthor Vitae Annamalai RajendranAuthor VitaeSoo Chool LeeAuthor Vitae Jae Chang KimAuthor VitaeSang Hak LeeAuthor Vitae Han Do GhimAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(2):897-902
Multiwalled carbon nanotubes (MWNTs) grafted chitosan (CS) nanowire (NW) was prepared by phase separation method. Glucose oxidase (GOx) was sequentially immobilized into MWNT-CS-NW to obtain MWNT-CS-NW/GOx biosensor. Field emission scanning electron microscopy (FESEM) images of MWNT-CS-NW/GOx reveals the existence of MWNT and CS. Cyclic voltammetry and amperometry were used to evaluate the electrochemical determination of glucose. The MWNT-CS-NW/GOx biosensor shows an excellent performance for glucose at +0.34 V with a high sensitivity (5.03 μA/mM) and lower response time (3 s) in a wide concentration range of 1-10 mM (correlation coefficient of 0.9988). In addition, MWNT-CS-NW/GOx biosensor possesses better reproducibility, storage stability and there is negligible interference from other electroactive components. 相似文献