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1.
Prolog is becoming a popular language in A. I. applications and particularly in the implementation of knowledge based expert systems. We have identified three different uses of Prolog: (1) building expert systems directly in ordinary Prolog, (2) using Prolog as the implementation language for an higher level of interpretation, and (3) extending Prolog with suitable features and directly using it. In this paper, we define the three uses in more details, compare them, and cite some concrete examples.  相似文献   

2.
An extension of Prolog, based on the model elimination theorem-proving procedure, would permit production of a logically complete Prolog technology theorem prover capable of performing inference operations at a rate approaching that of Prolog itself.  相似文献   

3.
The concept of set abstraction is introduced as a simple analogy of that of lambda abstraction in the theory of lambda calculus. The set abstraction is concerned with two extensions concerning Prolog language features: “set expression” and “predicate variable.” It has been argued in the literature that the set expression extension to Prolog does really contribute to the power of the language, while the extension of predicate variables does not add anything to Prolog. Combining these two concepts of extensions to Prolog, we define “set abstraction” as the set expression in which predicate variables are allowed as data objects. In other words, the set abstraction gets involved in the higher order predicate logic. By showing some application examples, it is demonstrated that with the help of predicate variables set abstractions can nicely handle the issues of the second order predicate logic. Further, the implementation programs written in Prolog and Concurrent Prolog are presented.  相似文献   

4.
This paper presents a parallel logic programming language named P-Prolog which is being developed as a logic programming language featuring both and- and or-parallelism. Compared with the other parallel logic programming languages, syntactic constructs such as read-only annotation,6) mode declaration2) and communication constraints7) are not used in P-Prolog. A new concept introduced in P-Prolog is the exclusive relation of guarded Horn clauses. Advances included in P-prolog. are:
  1. The synchronization mechanism can determine the direction of data flow dynamically.
  2. Guarded Horn clauses can be interpreted as eitherdon’t care nondeterminism ordon’t know non-determinism.
A prototype interpreter of P-Prolog has been implemented in C-Prolog. We are now implementing a P-Prolog interpreter in the C language.  相似文献   

5.
Radio frequency identification (RFID) is an important technique used for automatic identification and data capture. In recent years, low-cost RFID tags have been used in many open-loop applications beyond supply chain management, such as the tagging of the medicine, clothes, and belongings after the point of sales. At the same time, with the development of semiconductor industry, handheld terminals and mobile phones are becoming RFID-enabled. Unauthorized mobile RFID readers could be abused by the malicious hackers or curious common people. Even for authorized RFID readers, the ownership of the reader can be transferred and the owners of the authorized mobile reader may not be always reliable. The authorization and authentication of the mobile RFID readers need to take stronger security measures to address the privacy or security issues that may arise in the emerging open-loop applications. In this paper, the security demands of RFID tags in emerging open-loop applications are summarized, and two example protocols for authorization, authentication and key establishment based on symmetric cryptography are presented. The proposed protocols adopt a timed-session-based authorization scheme, and all reader-to-tag operations are authorized by a trusted third party using a newly defined class of timed sessions. The output of the tags is randomized to prevent unauthorized tracking of the RFID tags. An instance of the protocol A is implemented in 0.13-μm CMOS technology, and the functions are verified by field programmable gate array. The baseband consumes 44.0 μW under 1.08 V voltage and 1.92 MHz frequency, and it has 25,067 gate equivalents. The proposed protocols can successfully resist most security threats toward open-loop RFID systems except physical attacks. The timing and scalability of the two protocols are discussed in detail.  相似文献   

6.
Several attempts have been made to design a production system using Prolog. To construct a forward reasoning system, the rule interpreter is often written in Prolog, but its execution is slow. To develop an efficient production system, we propose a rule translation method where production rules are translated into a Prolog program and forward reasoning is done by the translated program. To translate the rules, we adopted the technique developed in BUP, the bottom-up parsing system in Prolog. Man-machine dialogue functions were added to the production system and showed the potential of our method to be applied to expert systems.  相似文献   

7.
MapReduce has been demonstrated to be a promising alternative to simplify parallel programming with high performance on single multicore machine. Compared to the cluster version, MapReduce does not have bottlenecks in disk and network I/O on single multicore machine, and it is more sensitive to characteristics of workloads. A single execution flow may be inefficient for many classes of workloads. For example, the fixed execution flow of the MapReduce program structure can impose significant overheads for workloads that inherently have only one emitted value per key, which are mainly caused by the unnecessary reduce phase. In this paper, we refine the workload characterization from Phoenix++ according to the attributes of key-value pairs, and give a demonstration that the refined workload characterization model covers all classes of MapReduce workloads. Based on the model, we propose a new MapReduce system with workload-customizable execution flow. The system, namely Peacock, is implemented on top of Phoenix++. Experiments with four different classes of benchmarks on a 16-core Intel-based server show that Peacock achieves better performance than Phoenix++ for workloads that inherently have only one emitted value per key (up to a speedup of \(3.6\times \) ) while identical for other classes of workloads.  相似文献   

8.
Process migration provides many benefits for parallel environments including dynamic load balancing, data access locality or fault tolerance. This paper describes an in-memory application-level checkpoint-based migration solution for MPI codes that uses the Hierarchical Data Format 5 (HDF5) to write the checkpoint files. The main features of the proposed solution are transparency for the user, achieved through the use of CPPC (ComPiler for Portable Checkpointing); portability, as the application-level approach makes the solution adequate for any MPI implementation and operating system, and the use of the HDF5 file format enables the restart on different architectures; and high performance, by saving the checkpoint files to memory instead of to disk through the use of the HDF5 in-memory files. Experimental results prove that the in-memory approach reduces significantly the I/O cost of the migration process.  相似文献   

9.
This paper suggests a general method for compiling OR-parallelism into AND-parallelism. An interpreter for an AND/OR-parallel language written in the AND-parallel subset of the language induces a source-to-source transformation from the full language into the AND-parallel subset. This transformation can be identified and implemented as a special purpose compiler or applied using a general purpose partial evaluator. The method is demonstrated to compile a variant of Concurrent Prolog into an AND-parallel subset of the language called Flat Concurrent Prolog (FCP). It is also shown applicable to the compilation of OR-parallel Prolog to FCP. The transformation identified is simple and efficient. The performance of the method is discussed in the context of programming examples. These compare well with conventionally compiled Prolog programs.  相似文献   

10.
As data exploration has increased rapidly in recent years, the datastore and data processing are getting more and more attention in extracting important information. To find a scalable solution to process the large-scale data is a critical issue in either the relational database system or the emerging NoSQL database. With the inherent scalability and fault tolerance of Hadoop, MapReduce is attractive to process the massive data in parallel. Most of previous researches focus on developing the SQL or SQL-like queries translator with the Hadoop distributed file system. However, it could be difficult to update data frequently in such file system. Therefore, we need a flexible datastore as HBase not only to place the data over a scale-out storage system, but also to manipulate the changeable data in a transparent way. However, the HBase interface is not friendly enough for most users. A GUI composed of SQL client application and database connection to HBase will ease the learning curve. In this paper, we propose the JackHare framework with SQL query compiler, JDBC driver and a systematical method using MapReduce framework for processing the unstructured data in HBase. After importing the JDBC driver to a SQL client GUI, we can exploit the HBase as the underlying datastore to execute the ANSI-SQL queries. Experimental results show that our approaches can perform well with efficiency and scalability.  相似文献   

11.
We present a method for preprocessing Prolog programs so that their operational semantics will be given by the first-order predicate calculus. Most Prolog implementations do not use a full unification algorithm, for efficiency reasons. The result is that it is possible to create terms having loops in them, whose semantics is not adequately described by first-order logic. Our method finds places where such loops may be created, and adds tests to detect them. This should not appreciably slow down the execution of most Prolog programs.  相似文献   

12.
13.
In this paper we present an extension of PROLOG using modal logic. A new deduction method is also given based on a rule closer to the classical inference rule of PROLOG.  相似文献   

14.
This paper presents an FPGA implementation of the quartic neuron model. This approach uses digital computation to emulate individual neuron behavior. We implemented the neuron model using fixed-point arithmetic operation. The neuron model’s computations are performed in arithmetic pipelines. It was designed in VHDL language and simulated prior to mapping in the FPGA. We show that the proposed FPGA implementation of the quartic neuron model can emulate the electrophysiological activities in various types of cortical neurons and is capable of producing a variety of different behaviors, with diversity similar to that of neuronal cells. The neuron family of this digital neuron can be modified by appropriately adjusting the neuron model’s parameters.  相似文献   

15.
This paper emphasis on state-of-the-art of the earlier until the current trend and demand, principles, design considerations, key performance and fabrication technology of RF MEMS switch devices developed over the past few years. RF MEMS switch performance and features such as actuation voltage, insertion loss, isolation and ease with cost of fabrication and applications are compared and discussed.  相似文献   

16.
17.
We study relations between Moore's interval test and Miranda's theorem. As an application we combine the (real) Newton iteration with a computational test for Miranda's hypothesis by Moore and Kioustelidis to find an approximate solution to the systemf(x)=0 with specified error bounds.  相似文献   

18.
On the basis of the analysis of JPEG error and stegonoise, we propose a novel quantitative steganalyzer for spatial ±1 steganography in JPEG decompressed images. First, we present a particular theoretical argument that the cover images, which are originally stored in JPEG format, can be approximately estimated through JPEG recompression with the detected quantization table. Then, on the basis of the relationship between the message embedding rate and the variance of the stegonoise in the discrete cosine transformation (DCT) domain, we construct a polynomial regression model to estimate the secret message length. The extensive experimental results show that the proposed scheme is computationally feasible and that it significantly outperforms the existing state-of-the-art estimators, especially for the images with high quality factors and embedding rates. The order of magnitude of the prediction error using the proposed scheme can remain in the 10?4 range, as measured by the median absolute difference. Moreover, our estimator is stable and robust with respect to the embedding rate and quality factor.  相似文献   

19.
In this work a unified treatment of solid and fluid vibration problems is developed by means of the Finite-Difference Time-Domain (FDTD). The scheme here proposed takes advantage from a scaling factor in the velocity fields that improves the performance of the method and the vibration analysis in heterogenous media. Moreover, the scheme has been extended in order to simulate both the propagation in porous media and the lossy solid materials. In order to accurately reproduce the interaction of fluids and solids in FDTD both time and spatial resolutions must be reduced compared with the set up used in acoustic FDTD problems. This aspect implies the use of bigger grids and hence more time and memory resources. For reducing the time simulation costs, FDTD code has been adapted in order to exploit the resources available in modern parallel architectures. For CPUs the implicit usage of the advanced vectorial extensions (AVX) in multi-core CPUs has been considered. In addition, the computation has been distributed along the different cores available by means of OpenMP directives. Graphic Processing Units have been also considered and the degree of improvement achieved by means of this parallel architecture has been compared with the highly-tuned CPU scheme by means of the relative speed up. The speed up obtained by the parallel versions implemented were up to 3 (AVX and OpenMP) and 40 (CUDA) times faster than the best sequential version for CPU that also uses OpenMP with auto-vectorization techniques, but non includes implicitely vectorial instructions. Results obtained with both parallel approaches demonstrate that massive parallel programming techniques are mandatory in solid-vibration problems with FDTD.  相似文献   

20.
Clustering analysis is one of the most commonly used data processing algorithms. Over half a century, K-means remains the most popular clustering algorithm because of its simplicity. Recently, as data volume continues to rise, some researchers turn to MapReduce to get high performance. However, MapReduce is unsuitable for iterated algorithms owing to repeated times of restarting jobs, big data reading and shuffling. In this paper, we address the problems of processing large-scale data using K-means clustering algorithm and propose a novel processing model in MapReduce to eliminate the iteration dependence and obtain high performance. We analyze and implement our idea. Extensive experiments on our cluster demonstrate that our proposed methods are efficient, robust and scalable.  相似文献   

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