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1.
The threat of cyber attacks motivates the need to monitor Internet traffic data for potentially abnormal behavior. Due to the enormous volumes of such data, statistical process monitoring tools, such as those traditionally used on data in the product manufacturing arena, are inadequate. “Exotic” data may indicate a potential attack; detecting such data requires a characterization of “typical” data. We devise some new graphical displays, including a “skyline plot,” that permit ready visual identification of unusual Internet traffic patterns in “streaming” data, and use appropriate statistical measures to help identify potential cyberattacks. These methods are illustrated on a moderate-sized data set (135,605 records) collected at George Mason University.  相似文献   

2.
The automatic generation of adjoints of mathematical models that are implemented as computer programs is receiving increased attention in the scientific and engineering communities. Reverse-mode automatic differentiation is of particular interest for large-scale optimization problems. It allows the computation of gradients at a small constant multiple of the cost for evaluating the objective function itself, independent of the number of input parameters. Source-to-source transformation tools apply simple differentiation rules to generate adjoint codes based on the adjoint version of every statement. In order to guarantee correctness, certain values that are computed and overwritten in the original program must be made available in the adjoint program. For their determination we introduce a static data-flow analysis called “to be recorded” analysis. Possible overestimation of this set must be kept minimal to get efficient adjoint codes. This efficiency is essential for the applicability of source-to-source transformation tools to real-world applications.  相似文献   

3.
This paper presents a new class of algorithms based on Youden designs to detect and restore edges present in an image imbedded by mixture or “salt and pepper” noise. The mixture noise consists of a uncorrelated or correlated noisy background plus uncorrelated impulsive noise. The objective is to restore pixels affected by the impulsive part of the mixture noise. The approach is to consider that these pixels have lost their true value and their estimate is obtained via the normal equation that yields the least sum of square error (LSSE). This procedure is known in the literature as “The Missing Value Approach Problem”. The estimates are introduced into the image data and an ANOVA technique based on Youden design is carried out. We introduce Youden designs which are special Symmetric Balanced Incomplete block (SBIB) designs, the pertinent statistical tests and estimates of the factor effects. We derive the estimate of the missing value for the uncorrelated noise environment as well as for the correlated one. The high level of performance of these algorithms can be evaluated visually via the input/output images and objectively via the input/output signal-to-noise ratio (SNR).  相似文献   

4.
Zikuan  Yang 《Pattern recognition》2001,34(12):2331-2338
With multiresolution decomposition and forest representation of wavelet transforms, we implemented a “from presence to classification” object-detection model. Three aspects of this model are studied. First, the presence of an object is quickly detected with fewer data manipulations at the coarsest resolution; secondly, object classification with high accuracy is fulfilled at the full resolution; and thirdly, the propagation in the coarse-to-fine process is studied in terms of coefficient propagation within a coefficient tree. We applied this model to internal deboned poultry inspection. As soon as the presence of a hazardous object was detected at a coarse resolution, a signal was actuated to reject the chicken fillet containing foreign inclusions before packing. Only with small foreign inclusions did we need to resort to finer resolution analysis.  相似文献   

5.
This paper presents a study of a complete robot axis including the electrical and the mechanical parts. The motorization of the robot arm presented here has been carried out using a DC motor, a “harmonic-drive” type gear system and three control loops (current, speed and position). Each component is studied and modeled taking into account non-linearities such as current limitation, backlash, low rigidity and non-linear friction. The results obtained through computation of the model are compared with measurements on the real arm (motor current and speed) using speed and position loops.  相似文献   

6.
We present a new foreign-function interface for SML/NJ. It is based on the idea of data-level interoperability—the ability of ML programs to inspect as well as manipulate C data structures directly.The core component of this work is an encoding of the almost2 complete C type system in ML types. The encoding makes extensive use of a “folklore” typing trick, taking advantage of ML's polymorphism, its type constructors, its abstraction mechanisms, and even functors. A small low-level component which deals with C struct and union declarations as well as program linkage is hidden from the programmer's eye by a simple program-generator tool that translates C declarations to corresponding ML glue code.  相似文献   

7.
An integrated learning object, a web-based inquiry environment “Young Scientist” for basic school level is introduced by applying the semiosphere conception for explaining learning processes. The study focused on the development of students’ (n = 30) awareness of the affordances of learning objects (LO) during the 3 inquiry tasks, and their ability of dynamically reconstructing meanings in the inquiry subtasks through exploiting these LO affordances in “Young Scientist”. The problem-solving data recorded by the inquiry system and the awareness questionnaire served as the data-collection methods.It was demonstrated that learners obtain complete awareness of the LO affordances in an integrated learning environment only after several problem-solving tasks. It was assumed that the perceived task-related properties and functions of LOs depend on students’ interrelations with LOs in specific learning contexts. Learners’ overall awareness of certain LO affordances, available in the inquiry system “Young Scientist”, developed with three kinds of patterns, describing the hierarchical development of the semiosphere model for learners. The better understanding of the LO affordances, characteristic to the formation of the functioning semiosphere, was significantly related to the advanced knowledge construction during these inquiry subtasks that presumed translation of information from one semiotic system to another. The implications of the research are discussed in the frames of the development of new contextual gateways for learning with virtual objects. It is assumed that effective LO-based learning has to be organized through pedagogically constrained gateways by manifesting certain LO affordances in the context in order to build up the dynamic semiosphere model for learners.  相似文献   

8.
The Inner Graphic Formula Method (IGF) which was originally conceived by Professor Ishiketa and further developed by him and his associates was used to investigate the motivation of new company employees.

Japanese companies traditionally recruit new employees from senior classes and notify successful candidates of their intention to employ them around the first of January. Since graduation is in March, April first is, then, the first day of work for almost all of these graduates in their new companies.

The investigation period for this study covers the eleven months from January until the middle of November, and therefore includes the three month period after notification but prior to actual work, from January first until March thirty-first, and the first eight month of actual work, from April first to the middle of November. The subjects fell, naturally, into two groups; a “Blue Collar” group and a “White Collar” group.

This paper deals with the motivation of these newly employed workers in general and, specifically, with the difference in motivational tendencies between “Blue Collar” and “White Collar” workers. As expected analysis showed that clear motivational differences appeared.

Motivation in the white collar workers tended to raise after an initial downturn, while a general downward trend was detected for the blue collar workers. White collar worker's attitudes toward themselves and toward their work seemed to change for the better as a result of having the chance to become introspective while plotting the graph and writing the anecdotal responses needed to complete the investigative sheet for this study.  相似文献   


9.
10.
Computer integrated manufacturing (CIM) is creating unexpected problems for a growing number of manufacturing companies. Manufacturers are finding it especially difficult to attract programmers who are both willing and able to develop the highly complex software that integrates existing accounting, sales, production, engineering, and quality control information subsystems. Consequently, many companies abdicate their responsibility for manufacturing information systems and seek third party support ranging from consulting assistance to a total takeover of the company's information resources and operations. Companies that “give away” their internal information system capabilities to third parties will ultimately lose control of their enterprise information, a danger to be avoided. Off-the-shelf software for desktop computers has become sufficiently powerful to help solve a major portion of this serious problem. We hypothesize that manufacturing engineers (and others) can be trained to use packaged software to leverage their company's systems programming capabilities. In effect they would become “paraprogrammers” who would help design, develop, and maintain manufacturing information systems. This new type of professional would not require a computer science or similar educational background, but could be trained to satisfy many specialized programming needs in a manner similar to how paramedics and paralegals are trained and used in the medical and legal professions, respectively. This paper reports on the early stages of research to determine whether or not product design engineers can use a desktop relational database management system and its various command languages to develop a master bill of material information system (BOMIS). The purpose of the research is to evaluate the amount of programming complexity reduction and increased operational effectiveness that can be achieved through paraprogramming by manufacturing engineers.  相似文献   

11.
Aihua Li  Yong Shi  Jing He   《Applied Soft Computing》2008,8(3):1259-1265
Cardholders’ behavior prediction is an important issue in credit card portfolio management. As a promising data mining approach, multiple criteria programming (MCLP) has been successfully applied to classify credit cardholders’ behavior into two groups. In order to better control credit risk for financial institutes, this paper proposes three methods based on MCLP to improve the “Bad” catching accuracy rate. One is called MCLP with unbalanced training set selection, the second is called fuzzy linear programming (FLP) method with moving boundary, and the third is called penalized multi criteria linear programming (PMCLP). The experimental examples demonstrate the promising performance of these methods.  相似文献   

12.
Josef Tomiska   《Calphad》2009,33(2):288-294
ExTherm 2” shows clear advances over ExTHERM as presented in [J. Tomiska, CALPHAD 26 (2002) 143–154]: All three parts have been improved in powerfulness, comfort, and interactive work. Especially the module cM3_ is now designed for interactive evaluation by means of an overall best fit technique applicable on experimental data from calorimetric and vapor pressure measurements as well as from measurements on the electromotive force (emf) on all types of metal alloy. The new data bank module cM1_(ETD/ ExP/ PhD) is an easy-to-handle tool for interactive work in many applications in physical chemistry. The data bank ETD has been enlarged by a series of new molar mixing properties of all types of metal alloy systems, and two sub-modules are added: The first tool, ExP, makes extrapolating binary data to a high number of ternary systems of all types of metal alloy possible. And the second tool, PhD, is designed for simple interactive computations on binary phase diagrams, especially for education items.  相似文献   

13.
以火电厂常用热电阻PT100为研究对象,采用泓格I-7033温度采集模块、德国SiKA TP17650M检验仪设计了动态试验系统,通过Visial Basic和DCON Utility软件实现了实验数据的自动采集,完成了PT100热电阻的动态特性试验,并使用MATLAB软件对实验数据进行了可视化研究,得出了该类型热电阻在不同电阻丝直径、不同插入深度以及不同被测温度下的数学模型,为该类型热电阻在火电厂安装、检修时提供必要的理论基础与实践指导。  相似文献   

14.
The paper presents an approach to characterizing a “stop–flow” mode of sensor array operation. The considered operation mode involves three successive phases of sensors exposure: flow (in a stream of measured gas), stop (in zero flow conditions) and recovery (in a stream of pure air). The mode was characterized by describing the distribution of information, which is relevant for classification of measured gases in the response of sensor array. The input data for classifier were the sets of sensors output values, acquired in discrete time moments of the measurement. Discriminant Function Analysis was used for data analysis. Organic vapours of ethanol, acetic acid and ethyl acetate in air were measured and classified. Our attention was focused on data sets which allowed for 100% efficient recognition of analytes. The number, size and composition of those data sets were examined versus time of sensor array response. This methodology allowed to observe the distribution of classification-relevant information in the response of sensor array obtained in “stop–flow” mode. Hence, it provided for the characterization of this mode.  相似文献   

15.
The goal of this paper is to offer a framework for classification of images and video according to their “type”, or “style”––a problem which is hard to define, but easy to illustrate; for example, identifying an artist by the style of his/her painting, or determining the activity in a video sequence. The paper offers a simple classification paradigm based on local properties of spatial or spatio-temporal blocks. The learning and classification are based on the naive Bayes classifier. A few experimental results are presented.  相似文献   

16.
17.
This paper presents a case of introducing new technology to a single stage in a maintenance operation composed of sequence of stages. The process - Thermal tile replacement - is a low volume, high value operation. A method for data collection at each stage, to estimate the variability in process quality, cost and duration is presented. The method involves: Identifying key product features, accuracy measure for each, rate of product rejection by feature and the associated probability density functions at each stage. The method relates accuracy variability by feature, “effect” to the contributing stage in the process “cause”. Simulation is used to justify the introduction of a new technology and to predict the percentage of product conformity in a “before” and “after” scenarios for the implementation of the new technology. The simulation model enables the quantification of technology impact on the product quality, overall productivity and the associated cost savings.  相似文献   

18.
Induction based fluidics (IBF), a new, simple patented approach for transporting liquids in the micro and the macro world, is discussed. Electric fields are shown to energize liquid/s in a container/s to execute an array of purposes. IBF is shown uniquely to energize N liquids in simple off the shelf devices, inductively. We discuss calibration and other issues, as we demonstrate how simple devices can dispense nanoliters and microliters with high precision and accuracy. Furthermore, we show preliminary single and eight channel data for the Zip Tip™ made by Millipore where the device transports liquids “electrically.” We briefly consider how such new devices, “electric” Zip Tips™, might automate desalting and the placement of digests for MALDI TOF analysis.  相似文献   

19.
In previous work with Bono we introduced a calculus for modelling “environment-aware” computations, that is computations that adapt their behavior according to the capabilities of the environment. The calculus is an imperative, object-based language (with extensible objects and primitives for discriminating the presence or absence of attributes of objects) equipped with a small-step operational semantics.In this paper we define a type and effect system for the calculus. The typing judgements specify, via constraints, the shape of environments which guarantees the correct execution of expressions and the typing rules track the effect of expression evaluation on the environment. The type and effect system is sound w.r.t. the operational semantics of the language.  相似文献   

20.
A study was conducted to assess the noise levels of popular Karaoke environments in Korea and the degree of potential noise-induced hearing loss due to commercial Karaoke noise. Using 18 subjects with normal hearing, a two-way, mixed-factors experimental design was used with two independent variables of “noise source” (no-singer, one-singer, and two-singer conditions) and “music type” (Trot, Ballad, and Rock music). For each experimental condition, average sound pressure levels and maximum sound pressure levels were measured. For assessing amount of temporary hearing threshold shift as a measure of potential hearing loss index, pure-tone audiometry was applied for measuring subjects’ hearing threshold levels of both ears before and after 100 min exposure to Karaoke noise. Questionnaires from 155 actual Karaoke users were also obtained to evaluate realistic user subjective perception on the Karaoke environment. Results showed that noise levels of typical Karaoke singing environments were higher than 95 dBA, with maximum noise levels often exceeded the US OSHA's non-permissible 115 dBA level. Further statistical analysis of hearing threshold shift revealed that up to 8 dB of significant hearing loss was found at the most important human hearing frequency band, centered at 4000 Hz, after about less than 2 h of Karaoke noise exposure, indicating that Karaoke facilities may pose a serious threat to noise-induced hearing loss. Along with some ergonomic/safety issues, practical hearing protection strategies are suggested and discussed.

Relevance to industry

Since noise levels from popular commercial Karaoke facilities are found to be potentially dangerous, the Karaoke-related industries, of supporting a big consumer market of entertainment, need to provide safer environments to protect naive users from potential hearing loss. Providing better design of Karaoke facilities with some ergonomic intervention strategies (such as proper sound absorptive treatment in Karaoke rooms, displaying warning signs of potential hearing loss, and setting up an upper safety volume limit in the Karaoke machine, etc.) may help those industries not only contribute for consumer protection but also develop better market with strong ethical and legal support in the future.  相似文献   


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