首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 390 毫秒
1.
A variant of the categorization-and-learning-module (CALM) network is presented that is not only capable of categorizing sequential information with feedback, but can adapt its resources to the current training set. In other words, the modules of the network may grow or shrink depending on the complexity of the presented sequence-set. In the original CALM algorithm, modules did not have access to activations from earlier stimulus presentations. To bypass this limitation, we introduced time-delay connections in CALM. These connections allow for a delayed propagation of activation, such that information at a given time will be available to a module at a later timestep. In addition, modules can autonomously add and remove resources depending on the structure and complexity of the task domain. The performance of this ontogenic CALM network with time-delay connections is demonstrated and analyzed using a sample set of overlapping sequences from an existing problem domain.  相似文献   

2.
《Computers & Education》1988,12(1):43-47
A Computer Aided Learning project in Mathematics (the CALM Project) is based at the Heriot-Watt University in Edinburgh. It is one of the projects currently in receipt of funding from the Computer Board of the United Kingdom as part of the Computers in Teaching Initiative in British Universities.The CALM Project seeks to produce computer enhanced teaching packages which will back-up the conventional teaching of Calculus to large groups of first year engineering undergraduates at a typical Scottish University. The project has been underway for just over one year and some of the software prepared by the CALM team has been tested by one section of the class. During this testing period we have embarked on a formative evaluation of the software and of its impact on student learning practices.In this article the writers present an outline of the evaluation procedure. In addition, details are given of the software tools used to produce the CALM programs.  相似文献   

3.
Logistics functions directly support the principal operation. In the international petroleum industry they mainly are maintenance, materials and transport. CALM is a microcomputer system which integrates the arrangement of these functions. It operates at the plant level.

There are six CALM subsystems: 1) equipment control; 2) maintenance work control; 3) materials control; 4) transport control; 5) budgeting and costs and 6) management reporting.

CALM is a collection of relational data bases and application programs. Its modules are distributed and are under user control. Data bases are designed for three organizational levels: 1) local area networks on microcomputers at the user level (CALM ); 2) relational data bases on minicomputers at the plant level and 3) relational data bases on main frame computers at the corporate level. This is said to be a 3-level computer system. Data base design is optimized over the three levels.

System integration requires strict discipline over the design of identification codes (equipment, spare parts, job plans, job orders, failure reports, etc.). The paper suggests standard code formats which have proved to be successful in industry.

Besides CALM, integrated systems from four multinational oil companies are discussed. Design errors experienced in these projects are described. Specific design precautions are emphasized.  相似文献   


4.
Original tools for teaching microprocessing concepts and applications in concrete terms are described. The tools, developed by a team of educators, include `logidules', the CALM (Common Assembly Language for Microprocessor) language, and the Dauphin (microprocessor) and Smaky (smart keyboard) systems. Courses taught using these tools are described  相似文献   

5.
This paper concentrates on the problem of designing and developing a spoken query retrieval (SQR) system to access large document databases via voice. The main challenge is to identify and address issues related to the adaptation and scalability of integrating automatic speech recognition (ASR) and information retrieval (IR). In this paper, a Context Aware Language Model (CALM) framework allowing information retrieval to large document databases via voice is presented and findings from a research study using the framework will be discussed as well.  相似文献   

6.
Generating molecules with desired properties is an important task in chemistry and pharmacy. An efficient method may have a positive impact on finding drugs to treat diseases like COVID-19. Data mining and artificial intelligence may be good ways to find an efficient method. Recently, both the generative models based on deep learning and the work based on genetic algorithms have made some progress in generating molecules and optimizing the molecule’s properties. However, existing methods have defects in the experimental evaluation standards. These methods also need to be improved in efficiency and performance. To solve these problems, we propose a method named the Chemical Genetic Algorithm for Large Molecular Space (CALM). Specifically, CALM employs a scalable and efficient molecular representation called molecular matrix. And we design corresponding crossover, mutation, and mask operators inspired by domain knowledge and previous studies. We apply our genetic algorithm to several tasks related to molecular property optimization and constraint molecular optimization. The results of these tasks show that our approach outperforms the other state-of-the-art deep learning and genetic algorithm methods, where the z tests performed on the results of several experiments show that our method is more than 99% likely to be significant. At the same time, based on the experimental results, we point out the defects in the experimental evaluation standard which affects the fair evaluation of all previous work. Avoiding these defects helps to objectively evaluate the performance of all work.  相似文献   

7.
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   

8.
顾冬梅 《自动化学报》1993,19(4):472-476
本文给出了当线性系统的传递函数为区间有理函数时的系统闭环鲁棒稳定性及多项式族δ~1(s)=sum from i=0 to m(Q_i(s)P_i(s))的鲁棒稳定的充要条件。Q_i(s)满足某些假定条件后,得出了δ(s)鲁棒稳定性的有限检验的充要条件。  相似文献   

9.
This paper presents a method for the design of PID-type controllers, including those augmented by a filter on the D element, satisfying a required gain margin and an upper bound on the (complementary) sensitivity for a finite set of plants. Important properties of the method are: (i) it can be applied to plants of any order including non-minimum phase plants, plants with delay, plants characterized by quasi-polynomials, unstable plants and plants described by measured data, (ii) the sensors associated with the PI terms and the D term can be different (i.e., they can have different transfer function models), (iii) the algorithm relies on explicit equations that can be solved efficiently, (iv) the algorithm can be used in near real-time to determine a controller for on-line modification of a plant accounting for its uncertainty and closed-loop specifications, (v) a single plot can be generated that graphically highlights tradeoffs among the gain margin, (complementary) sensitivity bound, low-frequency sensitivity and high-frequency sensor noise amplification, and (vi) the optimal controller for a practical definition of optimality can readily be identified.  相似文献   

10.
A linear (q,δ,,m(n))-locally decodable code (LDC) C : Fn → Fm(n) is a linear transformation from the vector space Fn to the space Fm(n) for which each message symbol xi can be recovered with probability at least 1/(|F|) +∈ from C(x) by a randomized algorithm that queries only q positions of C(x),even if up to δm(n) positions of C(x) are corrupted.In a recent work of Dvir,the author shows that lower bounds for linear LDCs can imply lower bounds for arithmetic circuits.He suggests that proving lower bounds for LDCs over the complex or real field is a good starting point for approaching one of his conjectures.Our main result is an m(n) = Ω (n2) lower bound for linear 3-query LDCs over any,possibly infinite,field.The constant in the Ω (·) depends only on ε and δ.This is the first lower bound better than the trivial m(n) = Ω (n) for arbitrary fields and more than two queries.  相似文献   

11.
Modeling and Analysis of Workflows Using Petri Nets   总被引:37,自引:0,他引:37  
A workflow system, in its general form, is basically a heterogeneous and distributed information system where the tasks are performed using autonomous systems. Resources, such as databases, labor, etc. are typically required to process these tasks. Prerequisite to the execution of a task is a set of constraints that reflect the applicable business rules and user requirements.In this paper we present a Petri Net (PN) based framework that (1) facilitates specification of workflow applications, (2) serves as a powerful tool for modeling the system under study at a conceptual level, (3) allows for a smooth transition from the conceptual level to a testbed implementation and (4) enables the analysis, simulation and validation of the system under study before proceeding to implementation. Specifically, we consider three categories of task dependencies: control flow, value and external (temporal).We identify several structural properties of PN and demonstrate their use for conducting the following type of analyses: (1) identify inconsistent dependency specifications among tasks; (2) test for workflow safety, i.e. test whether the workflow terminates in an acceptable state; (3) for a given starting time, test whether it is feasible to execute a workflow with the specified temporal constraints. We also provide an implementation for conducting the above analyses.  相似文献   

12.
The EVA (espacios virtuales de aprendizaje, or virtual learning spaces) project applies artificial intelligence tools to teleteaching methods, in a way that eliminates or mitigates the need for synchronous and in situ education. (A) A taxonomy of the space of knowledge (also called ‘Learning Space'; currently our prototype teaches M.Sc. courses in Computer Science) is formed and discretized. (B) EVA finds each student's initial knowledge state (through a computer examination) and final (desired) knowledge state, and from these, a particular learning trajectory is designed for that student. (C) Personalized books (called polybooks, because they are formed by modules (chapters) written in a variety of media) are armed by concatenating — along the learning trajectory — modules from a large pool, and sent to the student through the net in a store-and-forward fashion. (D) EVA searches the net for teaching material which has not been indexed in the discretized learning space, using a tool (Clasitex) inside an agent that finds the main themes or topics that an article (written in natural language) covers. (E) EVA also schedules for each student synchronous activities (lectures in TV, teleconferences, on-line question and answering sessions, chats). (F) EVA suggests for each student suitable ‘classmates' (students having similar learning trajectories) in her town, as well as possible advisers (students or alumni having knowledge that the student is acquiring). The present status, problems, models and tools of EVA are presented.  相似文献   

13.
Target design methodologies (DfX) were developed to cope with specific engineering design issues such as cost-effectiveness, manufacturability, assemblability, maintainability, among others. However, DfX methodologies are undergoing the lack of real integration with 3D CAD systems. Their principles are currently applied downstream of the 3D modelling by following the well-known rules available from the literature and engineers’ know-how (tacit internal knowledge).This paper provides a method to formalize complex DfX engineering knowledge into explicit knowledge that can be reused for Advanced Engineering Informatics to aid designers and engineers in developing mechanical products. This research work wants to define a general method (ontology) able to couple DfX design guidelines (engineering knowledge) with geometrical product features of a product 3D model (engineering parametric data). A common layer for all DfX methods (horizontal) and dedicated layers for each DfX method (vertical) allow creating the suitable ontology for the systematic collection of the DfX rules considering each target. Moreover, the proposed framework is the first step for developing (future work) a software tool to assist engineers and designers during product development (3D CAD modelling).A design for assembly (DfA) case study shows how to collect assembly rules in the given framework. It demonstrates the applicability of the CAD-integrated DfX system in the mechanical design of a jig-crane. Several benefits are recognized: (i) systematic collection of DfA rules for informatics development, (ii) identification of assembly issues in the product development process, and (iii) reduction of effort and time during the design review.  相似文献   

14.
15.
Contrastive to Part 1, Part 2 presents a generalised optimal linear quadratic digital tracker (LQDT) with universal applications for the discrete-time (DT) systems. This includes (1) a generalised optimal LQDT design for the system with the pre-specified trajectories of the output and the control input and additionally with both the input-to-output direct-feedthrough term and known/estimated system disturbances or extra input/output signals; (2) a new optimal filter-shaped proportional plus integral state-feedback LQDT design for non-square non-minimum phase DT systems to achieve a minimum-phase-like tracking performance; (3) a new approach for computing the control zeros of the given non-square DT systems; and (4) a one-learning-epoch input-constrained iterative learning LQDT design for the repetitive DT systems.  相似文献   

16.
This paper deals with the problem of finding the optimum site for a railway station for the city of Mashhad, northeast Iran, using the methods of analytical hierarchy process (AHP) and data envelopment analysis (DEA). The paper identifies a four-level hierarchy model for the railway station site-selection problem. The model uses four main criteria: (1) rail-related, (2) passenger services, (3) architecture and urbanism, and (4) economics. In addition, there are 26 subcriteria as well as five (potential) candidates or alternatives. Comparison matrices are used to obtain the local weights and priorities of the railway-station candidates. A DEA model is proposed to determine the optimum site for a railway station. It is shown that the local priorities (or weights) obtained from the AHP can be defined as the multiple outputs of a DEA model for finding the best site for a railway station.  相似文献   

17.
A computational methodology for the simulation of the transient aeroelastic response of an unrestrained and flexible aircraft during high-G maneuvers is presented. The key components of this methodology are: (a) a three-field formulation for coupled fluid/structure interaction problems; (b) a second-order time-accurate and geometrically conservative flow solver for CFD computations on unstructured dynamic meshes; (c) a corotational finite element method for the solution of geometrically nonlinear and unrestrained structural dynamics problems; (d) a robust method for updating an unrestrained and unstructured moving fluid mesh; and (e) a second-order time-accurate staggered algorithm for time-integrating the coupled fluid/structure semi-discrete equations of motion. This computational methodology is illustrated with the simulation on a parallel processor of several three-dimensional high-G pullup maneuvers of the Langley Fighter in the transonic regime, using a detailed finite element aeroelastic model.  相似文献   

18.
“Words lie in our way”   总被引:1,自引:1,他引:0  
The central claim of computationalism is generally taken to be that the brain is a computer, and that any computer implementing the appropriate program would ipso facto have a mind. In this paper I argue for the following propositions: (1) The central claim of computationalism is not about computers, a concept too imprecise for a scientific claim of this sort, but is about physical calculi (instantiated discrete formal systems). (2) In matters of formality, interpretability, and so forth, analog computation and digital computation are not essentially different, and so arguments such as Searle's hold or not as well for one as for the other. (3) Whether or not a biological system (such as the brain) is computational is a scientific matter of fact. (4) A substantive scientific question for cognitive science is whether cognition is better modeled by discrete representations or by continuous representations. (5) Cognitive science and AI need a theoretical construct that is the continuous analog of a calculus. The discussion of these propositions will illuminate several terminology traps, in which it's all too easy to become ensnared.  相似文献   

19.
《Advanced Robotics》2013,27(1):115-135
This paper presents a new framework for path planning based on artificial potential functions (APFs). In this scheme, the APFs for path planning have a multiplicative and additive composition between APFs for goal destination and APFs for obstacle avoidance, unlike conventional composition where the APF for obstacle avoidance is added to the APF for goal destination. In particular, this paper presents a set of analytical guidelines for designing potential functions to avoid local minima for a number of representative scenarios based on the proposed framework for path planning. Specifically the following cases are addressed: (i) a non-reachable goal problem (a case in which the potential of the goal is overwhelmed by the potential of an obstacle), (ii) an obstacle collision problem (a case in which the potential of the obstacle is overwhelmed by the potential of the goal) and (iii) a narrow passage problem (a case in which the potential of the goal is overwhelmed by the potential of two obstacles). The example results for each case show that the proposed scheme can effectively construct a path-planning system with the capability of reaching a goal and avoiding obstacles despite possible local minima.  相似文献   

20.
A BASIC program is presented for significance tests to determine whether a dendrogram is derived from clustering of points that belong to a single multivariate normal distribution. The significance tests are based on statistics of the Kolmogorov—Smirnov type, obtained by comparing the observed cumulative graph of branch levels with a graph for the hypothesis of multivariate normality. The program also permits testing whether the dendrogram could be from a cluster of lower dimensionality due to character correlations.The program makes provision for three similarity coefficients, (1) Euclidean distances, (2) squared Euclidean distances, and (3) Simple Matching Coefficients, and for five cluster methods (1) WPGMA, (2) UPGMA, (3) Single Linkage (or Minimum Spanning Trees), (4) Complete Linkage, and (5) Ward's Increase in Sums of Squares. The program is entitled DENBRAN.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号