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1.
The capability-based distributed layout approach was first proposed by Baykasoğlu (Int J Prod Res 41, 2597–2618, 2003) for
job shops which are working under highly volatile manufacturing environments in order to avoid high reconfiguration costs.
It was argued that the capability-based distributed layout can also be a valid (or better) option for “classical functional
layouts” which are generally operating under “high variety” and “low-stable demand”. In this paper first the capability-based
distributed layout approach and related issues are reviewed and discussed afterwards the performance of “Capability Based
Distributed Layout: (CB-DL)” is tested via extensive simulation experiments. After the simulation experiments, it is observed
that capability-based distributed layout has a big potential and can also be considered as an alternative to classical process
types of layouts. 相似文献
2.
Ramakrishnan Ramanathan 《Electronic Commerce Research》2010,10(2):191-208
We explore in this paper how performance of e-commerce websites in terms of various criteria influences customers’ intention
to shop again in the same website. Our approach is based on an interesting use of statistical regression in the hotel literature
that attempted to classify different cues in hotels as critical, satisfier, dissatisfier, etc. We use online ratings for 484
e-commerce websites for this study. Our study shows that “satisfaction with claims” is the single most important criterion
valued as critical by online customers. “Comparative prices” and “Refunds/returns” are desirable criteria. “Management accessibility”,
“Payment process” and “Privacy experience” are satisfiers while “on-time delivery” is a dissatisfier. 相似文献
3.
W. M. P. van der Aalst V. Rubin H. M. W. Verbeek B. F. van Dongen E. Kindler C. W. Günther 《Software and Systems Modeling》2010,9(1):87-111
Process mining includes the automated discovery of processes from event logs. Based on observed events (e.g., activities being
executed or messages being exchanged) a process model is constructed. One of the essential problems in process mining is that
one cannot assume to have seen all possible behavior. At best, one has seen a representative subset. Therefore, classical synthesis techniques are not suitable as they aim at
finding a model that is able to exactly reproduce the log. Existing process mining techniques try to avoid such “overfitting” by generalizing the model to allow for more behavior.
This generalization is often driven by the representation language and very crude assumptions about completeness. As a result,
parts of the model are “overfitting” (allow only for what has actually been observed) while other parts may be “underfitting”
(allow for much more behavior without strong support for it). None of the existing techniques enables the user to control
the balance between “overfitting” and “underfitting”. To address this, we propose a two-step approach. First, using a configurable
approach, a transition system is constructed. Then, using the “theory of regions”, the model is synthesized. The approach
has been implemented in the context of ProM and overcomes many of the limitations of traditional approaches. 相似文献
4.
5.
Erik Hollnagel’s body of work in the past three decades has molded much of the current research approach to system safety,
particularly notions of “error”. Hollnagel regards “error” as a dead-end and avoids using the term. This position is consistent
with Rasmussen’s claim that there is no scientifically stable category of human performance that can be described as “error”.
While this systems view is undoubtedly correct, “error” persists. Organizations, especially formal business, political, and
regulatory structures, use “error” as if it were a stable category of human performance. They apply the term to performances
associated with undesired outcomes, tabulate occurrences of “error”, and justify control and sanctions through “error”. Although
a compelling argument can be made for Hollnagel’s view, it is clear that notions of “error” are socially and organizationally
productive. The persistence of “error” in management and regulatory circles reflects its value as a means for social control. 相似文献
6.
Facial expression recognition of a speaker using front-view face judgment, vowel judgment, and thermal image processing 总被引:1,自引:1,他引:0
Tomoko Fujimura Yasunari Yoshitomi Taro Asada Masayoshi Tabuse 《Artificial Life and Robotics》2011,16(3):411-417
For facial expression recognition, we selected three images: (i) just before speaking, (ii) speaking the first vowel, and
(iii) speaking the last vowel in an utterance. In this study, as a pre-processing module, we added a judgment function to
distinguish a front-view face for facial expression recognition. A frame of the front-view face in a dynamic image is selected
by estimating the face direction. The judgment function measures four feature parameters using thermal image processing, and
selects the thermal images that have all the values of the feature parameters within limited ranges which were decided on
the basis of training thermal images of front-view faces. As an initial investigation, we adopted the utterance of the Japanese
name “Taro,” which is semantically neutral. The mean judgment accuracy of the front-view face was 99.5% for six subjects who
changed their face direction freely. Using the proposed method, the facial expressions of six subjects were distinguishable
with 84.0% accuracy when they exhibited one of the intentional facial expressions of “angry,” “happy,” “neutral,” “sad,” and
“surprised.” We expect the proposed method to be applicable for recognizing facial expressions in daily conversation. 相似文献
7.
Janet Rothwell Zuhair Bandar James O’Shea David McLean 《Neural computing & applications》2007,16(4-5):327-339
This paper describes the application of a backpropagation artificial neural network (ANN) for charting the behavioural state
of previously unseen persons. In a simulated theft scenario participants stole or did not steal some money and were interviewed
about the location of the money. A video of each interview was presented to an automatic system, which collected vectors containing
nonverbal behaviour data. Each vector represented a participant’s nonverbal behaviour related to “deception” or “truth” for
a short period of time. These vectors were used for training and testing a backpropagation ANN which was subsequently used
for charting the behavioural state of previously unseen participants. Although behaviour related to “deception” or “truth”
is charted the same strategy can be used to chart different psychological states over time and can be tuned to particular
situations, environments and applications.
We thank those who kindly volunteered to participate in the study. 相似文献
8.
Thomas Kühne 《Software and Systems Modeling》2006,5(4):369-385
With the recent trend to model driven engineering a common understanding of basic notions such as “model” and “metamodel” becomes a pivotal issue. Even though these notions have been in widespread use for quite a while, there is still little consensus about when exactly it is appropriate to use them. The aim of this article is to start establishing a consensus about generally acceptable terminology. Its main contributions are the distinction between two fundamentally different kinds of model roles, i.e. “token model” versus “type model” (The terms “type” and “token” have been introduced by C.S. Peirce, 1839–1914.), a formal notion of “metaness”, and the consideration of “generalization” as yet another basic relationship between models. In particular, the recognition of the fundamental difference between the above mentioned two kinds of model roles is crucial in order to enable communication among the model driven engineering community that is free of both unnoticed
misunderstandings and unnecessary disagreement. 相似文献
9.
In 1675, English scientist Robert Hooke discovered “the true... ...manner of arches for building,” which he summarized with
a single phrase: “As hangs the flexible line, so but inverted will stand the rigid arch.” In the centuries that followed,
Hooke’s simple idea has been used to understand and design numerous important works. Recent research at MIT on the interactive
analysis of structural forces provides new graphical tools for the understanding of arch behavior, which are useful for relating
the forces and geometry of masonry structures. The key mathematical principle is the use of graphical analysis to determine
possible equilibrium states. 相似文献
10.
In recent years, fierce market competition has increased the need for incorporating manufacturing flexibility into product
styling. The product styling platform approach proposed in this paper offers an insight into how this challenge can be dealt
with by transforming an existing product fashion into an intangible styling module with the view to refreshing its appeal.
This paper addresses the important issues of how the approach can be turned into a robust applicational tool to facilitate
the design of product families to satisfy diverse customer needs. The paper investigates the nature and quantification of
modular styling. By capturing and analysing design experts’ opinions on product styling, the evolution of a fashion can be
quantified in the form of a schema of diffusion styles. The study has also led to the development of the ideas of “Prompt
Time Market Segmentation Grid” and the “Active Style Diagnosis”. The concepts are applied in an “Active Product Styling Platform”
with scalable and expandable capabilities to enhance the effectiveness of conventional product styling practices. This approach
can also help the formation of product style families and facilitate the development of products particularly in a mass customisation
environment. 相似文献
11.
邵志清 《计算机科学技术学报》1993,8(2):155-161
In this paper we try to introduce a new approach to operational semantics of recursive programs by using ideas in the“priority method”which is a fundamental tool in Recursion Theory.In lieu of modelling partial functions by introducing undefined values in a traditional approach,we shall define a priority derivation tree for every term,and by respecting thr rule“attacking the subtem of the highest priority first”we define transition relations,computation sequences etc.directly based on a standard interpretation whic includes no undefined value in its domain,Finally,we prove that our new approach generates the same opeational semantics as the traditional one.It is also pointed out that we can use our strategy oto refute a claim of Loeckx and Sieber that the opperational semantics of recursive programs cannot be built based on predicate logic. 相似文献
12.
A. F. Newell P. Gregor M. Morgan G. Pullin C. Macaulay 《Universal Access in the Information Society》2011,10(3):235-243
Although “User-Centred”, “Participatory”, and other similar design approaches have proved to be very valuable for mainstream
design, their principles are more difficult to apply successfully when the user group contains, or is composed of, older and/or
disabled users. In the field of design for older and disabled people, the “Universal Design”, “Inclusive Design” and “Design
for All” movements have encouraged designers to extend their design briefs to include older and disabled people. The downside
of these approaches is that they can tend to encourage designers to follow a traditional design path to produce a prototype
design, and only then investigate how to modify their interfaces and systems to cope with older and/or disabled users. This
can lead to an inefficient design process and sometimes an inappropriate design, which may be “accessible” to people with
disabilities, but in practice unusable. This paper reviews the concept that the authors have called “User-Sensitive Inclusive
Design”, which suggests a different approach to designing for marginalised groups of people. Rather than suggesting that designers
rely on standards and guidelines, it is suggested that designers need to develop a real empathy with their user groups. A
number of ways to achieve this are recommended, including the use of ethnography and techniques derived from professional
theatre both for requirements gathering and for improving designers’ empathy for marginalised groups of users, such as older
and disabled people. 相似文献
13.
The minority game (MG) comes from the so-called “El Farol bar” problem by W.B. Arthur. The underlying idea is competition
for limited resources and it can be applied to different fields such as: stock markets, alternative roads between two locations
and in general problems in which the players in the “minority” win. Players in this game use a window of the global history
for making their decisions, we propose a neural networks approach with learning algorithms in order to determine players strategies.
We use three different algorithms to generate the sequence of minority decisions and consider the prediction power of a neural
network that uses the Hebbian algorithm. The case of sequences randomly generated is also studied.
Research supported by Local Project 2004–2006 (EX 40%) Università di Foggia. A. Sfrecola is a researcher financially supported
by Dipartimento di Scienze Economiche, Matematiche e Statistiche, Università degli Studi di Foggia, Foggia, Italy. 相似文献
14.
Antti Oulasvirta Tye Rattenbury Lingyi Ma Eeva Raita 《Personal and Ubiquitous Computing》2012,16(1):105-114
Examining several sources of data on smartphone use, this paper presents evidence for the popular conjecture that mobile devices
are “habit-forming.” The form of habits we identified is called a checking habit: brief, repetitive inspection of dynamic content quickly accessible on the device. We describe findings on kinds and frequencies
of checking behaviors in three studies. We found that checking habits occasionally spur users to do other things with the
device and may increase usage overall. Data from a controlled field experiment show that checking behaviors emerge and are
reinforced by informational “rewards” that are very quickly accessible. Qualitative data suggest that although repetitive
habitual use is frequent, it is experienced more as an annoyance than an addiction. We conclude that supporting habit-formation
is an opportunity for making smartphones more “personal” and “pervasive.” 相似文献
15.
This paper discusses a study on the mechanism of self-organization. A global order is organized by the simple and locally
coordinated actions of autonomous agents using only local information, so complex or globally coordinated actions which use
global communication and high-level strategies are not necessary. The fundamental factors for establishing a global order
using self-organization are a “dissipative structure,” an “autocatalysis mechanism,” and “intentional fluctuations.” If an
environment where there are agents has a dissipative structure and those agents have some sort of autocatalysis and intentional
fluctuation mechanisms within themselves, it is possible to form a global order for them using only their simple and locally
coordinated actions. “The blind-hunger dilemma” is used as an example to simulate the self-organization and coordinated actions
of agents. In this simulation environment, there are many ant-like agents which must get energy. However, there is only one
small energy supply base, so either an efficient method or the coordinated actions of agents is needed. As a result, the agents
using our approach could move and get energy more efficiently than agents using conventional coordination mechanisms involving
global communication and high-level strategies.
Real World Computing Partnership
This work was presented, in part, at the Second International Symposium on Artificial Life and Robotics, Oita, Japan, February
18–20, 1997 相似文献
16.
Massively multi-player games hold a huge market in the digital entertainment industry. Companies invest heavily in game developments
since a successful online game can attract millions of users, and this translates to a huge investment payoff. However, multi-player
online games are also subjected to various forms of “hacks” and “cheats”. Hackers can alter the graphic rendering to reveal
information otherwise be hidden in a normal game, or cheaters can use software robots to play the game automatically and thus
gain an unfair advantage. To overcome these problems, some popular online games release software patches constantly to block
“known” hacks or incorporate anti-cheating software to detect “known” cheats. This not only creates deployment difficulty
but new cheats will still be able to breach the normal game logic until software patches or updates of the anti-cheating software
are available. Moreover, the anti-cheating software themselves are also vulnerable to hacks. In this paper, we propose a “scalable”
and “efficient” method to detect whether a player is cheating or not. The methodology is based on the dynamic Bayesian network
approach. The detection framework relies solely on the game states and runs in the game server only. Therefore, it is invulnerable
to hacks and it is a much more deployable solution. To demonstrate the effectiveness of the proposed method, we have implemented
a prototype multi-player game system to detect whether a player is using any “aiming robot” for cheating or not. Experiments
show that the proposed method can effectively detect cheaters on a first-person shooter game with extremely low false positive
rate. We believe the proposed methodology and the prototype system provide a first step toward a systematic study of cheating
detection and security research in the area of online multi-player games. 相似文献
17.
A. A. Voina 《Cybernetics and Systems Analysis》2011,47(4):649-658
This paper considers the possibility of using a multidimensional compound Poisson process controlled by a continuous-time
Markov chain in mathematical decision-making models. A definition of this process is presented and examples are given that
illustrate its use in formalizing the concepts of “uncertainty” and “risk” and constructing risk functions and objective functions
for the corresponding optimization problems. Some approaches are proposed to solve these problems, in particular, a direct
analytic approach consisting of finding explicit formulas for a risk function and a method of approximate solution based on
limit theorems of stochastic process theory. 相似文献
18.
Daniel S. Yeung Defeng Wang Wing W. Y. Ng Eric C. C. Tsang Xizhao Wang 《Machine Learning》2007,68(2):171-200
This paper proposes a new large margin classifier—the structured large margin machine (SLMM)—that is sensitive to the structure
of the data distribution. The SLMM approach incorporates the merits of “structured” learning models, such as radial basis
function networks and Gaussian mixture models, with the advantages of “unstructured” large margin learning schemes, such as
support vector machines and maxi-min margin machines. We derive the SLMM model from the concepts of “structured degree” and
“homospace”, based on an analysis of existing structured and unstructured learning models. Then, by using Ward’s agglomerative
hierarchical clustering on input data (or data mappings in the kernel space) to extract the underlying data structure, we
formulate SLMM training as a sequential second order cone programming. Many promising features of the SLMM approach are illustrated,
including its accuracy, scalability, extensibility, and noise tolerance. We also demonstrate the theoretical importance of
the SLMM model by showing that it generalizes existing approaches, such as SVMs and M4s, provides novel insight into learning models, and lays a foundation for conceiving other “structured” classifiers.
Editor: Dale Schuurmans.
This work was supported by the Hong Kong Research Grant Council under Grants G-T891 and B-Q519. 相似文献
19.
Design and analysis of a video-on-demand server 总被引:6,自引:0,他引:6
The availability of high-speed networks, fast computers and improved storage technology is stimulating interest in the development
of video on-demand services that provide facilities similar to a video cassette player (VCP). In this paper, we present a
design of a video-on-demand (VOD) server, capable of supporting a large number of video requests with complete functionality
of a remote control (as used in VCPs), for each request. In the proposed design, we have used an interleaved storage method
with constrained allocation of video and audio blocks on the disk to provide continuous retrieval. Our storage scheme interleaves
a movie with itself (while satisfying the constraints on video and audio block allocation. This approach minimizes the starting delay and the
buffer requirement at the user end, while ensuring a jitter-free display for every request. In order to minimize the starting
delay and to support more non-concurrent requests, we have proposed the use of multiple disks for the same movie. Since a
disk needs to hold only one movie, an array of inexpensive disks can be used, which reduces the overall cost of the proposed
system. A scheme supported by our disk storage method to provide all the functions of a remote control such as “fast-forwarding”,
“rewinding” (with play “on” or “off”), “pause” and “play” has also been discussed. This scheme handles a user request independent
of others and satisfies it without degrading the quality of service to other users. The server design presented in this paper
achieves the multiple goals of high disk utilization, global buffer optimization, cost-effectiveness and high-quality service
to the users. 相似文献
20.
This paper identifies a widely existing phenomenon in social media content, which we call the “words of few mouths” phenomenon.
This phenomenon challenges the development of recommender systems based on users’ online opinions by presenting additional
sources of uncertainty. In the context of predicting the “helpfulness” of a review document based on users’ online votes on
other reviews (where a user’s vote on a review is either HELPFUL or UNHELPFUL), the “words of few mouths” phenomenon corresponds to the case where a large fraction of the reviews are each voted only
by very few users. Focusing on the “review helpfulness prediction” problem, we illustrate the challenges associated with the
“words of few mouths” phenomenon in the training of a review helpfulness predictor. We advocate probabilistic approaches for
recommender system development in the presence of “words of few mouths”. More concretely, we propose a probabilistic metric
as the training target for conventional machine learning based predictors. Our empirical study using Support Vector Regression
(SVR) augmented with the proposed probability metric demonstrates advantages of incorporating probabilistic methods in the
training of the predictors. In addition to this “partially probabilistic” approach, we also develop a logistic regression
based probabilistic model and correspondingly a learning algorithm for review helpfulness prediction. We demonstrate experimentally
the superior performance of the logistic regression method over SVR, the prior art in review helpfulness prediction. 相似文献