Unequal Importance Research Articles

АКТУАЛЬНАЯ КОМПЬЮТЕРНАЯ ЛЕКСИКА В АССОЦИАЦИЯХ ШКОЛЬНИКОВ

The work is based on the materials of the Associative Dictionary of Saratov schoolchildren; it represents the research of the structure of the so-called computer lexicon in the associations of schoolchildren. It is shown that the computer words are a part of the vocabulary of all age groups, and that their importance increases as the schoolchildren become more mature. The data of the associative dictionary allow to reveal a number of factors (age, sex, place of residence, type of educational institution) defining unequal importance of the computer vocabulary in the language consciousness of different groups of schoolchildren.

News and households’ subjective macroeconomic expectations

The purpose of the present paper is to provide microfoundations of how households form subjective expectations of the macroeconomy. We focus on the role of perceived news; distinguishing between good and bad news. The paper introduces a testable model where households give unequal importance (or weights) to ‘good’ and ‘bad’ news. The model is empirically verified using household survey data compiled for the US. The results indicate clearly that households give no weight to bad news in the long-run.

Generalized Butterfly Graph and Its Application to Video Stream Authentication

This paper presents the generalized butterfly graph (GBG) and its application to video stream authentication. Compared with the original butterfly graph, the proposed GBG provides significantly increased flexibility, which is necessary for streaming applications, including supporting arbitrary bit-rate budget for authentication and arbitrary number of video packets. Within the GBG design, the problem of constructing an authentication graph is defined as follows: given the total number of packets to protect, the expected packet loss rate for the network, and the available overhead budget, how should one design the authentication graph to maximize the probability that the received packets are verifiable? Furthermore, given the fact that media packets are typically of unequal importance, we explore two variants of the GBG authentication, packet sorting and unequal authentication protection, which apply unequal treatment to different packets based on their importance. Lastly, we examine how the proposed GBG authentication can be applied within the context of rate-distortion-authentication (R-D-A) optimized streaming: given a media stream protected by GBG authentication, the R-D-A optimized streaming technique computes an optimized transmission schedule by recognizing and accounting for the authentication dependencies in the GBG authentication graph.

Multiuser Distortion Management Scheme for H.264 Video Transmission in OFDM Systems

In this paper, we propose a subcarrier resource allocation algorithm for managing the video quality degradation for multiuser orthogonal frequency division multiplex (OFDM) systems. The proposed algorithm exploits the unequal importance existing in different picture types for video coding and the diversity of subcarriers for multiuser systems. A model-based performance metric is first derived considering the error concealment and error propagation properties of the H.264 video coding structure. Based on the information on video quality enhancement existing in a packet to be transmitted, we propose the distortion management algorithm for balancing the subcarriers and power usages for each user and minimizing the overall video quality degradation. In the simulation results, the proposed algorithm demonstrates a more gradual video quality degradation for different numbers of users compared with other resource allocation schemes.

Thermosolutal Convection During Melting in a Porous Medium Saturated with Aqueous Solution

The thermosolutal convection in a porous medium saturated with an aqueous solution near the temperature of the density maximum is studied. The fixed temperatures applied to vertical walls include the density maximum. The formulation of the problem is based on the Darcy-Brinkman model and the density variation is governed by a nonlinear approximation. The equations are solved by a finite-volume method. The numerical model is validated through experimental results. We show that the nonlinear variation of the density influences strongly the flow structure and the heat transfer. The structures of this flow show that the density maximum generates a complex flow structure of two contrarotating cells of unequal importance.

Layer-weighted unequal error protection for scalable video coding extension of H.264/AVC

The scalable video coding extension of H.264/AVC is a current standardization project. This paper deals with unequal error protection (UEP) scheme for scalable video bitstream over packet-lossy networks using forward error correction (FEC). The proposed UEP scheme is developed by exploiting jointly the unequal importance existing both in temporal layers and quality layers of hierarchial scalable video bitstream. For efficient assignment of FEC codes, the proposed UEP scheme uses a simple and efficient performance metric, namely layer-weighted expected zone of error propagation (LW-EZEP). The LW-EZEP is adopted for quantifying the error propagation effect on video quality degradation from packet loss in temporal layers and in quality layers. Compared to other UEP schemes, the proposed UEP scheme demonstrates strong robustness and adaptation for variable channel status.

Quality-Optimized and Secure End-to-End Authentication for Media Delivery

The need for security services, such as confidentiality and authentication, has become one of the major concerns in multimedia communication applications, such as video on demand and peer-to-peer content delivery. Conventional data authentication cannot be directly applied for streaming media when an unreliable channel is used and packet loss may occur. This paper begins by reviewing existing end-to-end media authentication schemes, which can be classified into stream-based and content-based techniques. We then motivate and describe how to design authentication schemes for multimedia delivery that exploit the unequal importance of different packets. By applying conventional cryptographic hashes and digital signatures to the media packets, the system security is similar to that achievable in conventional data security. However, instead of optimizing packet verification probability, we optimize the quality of the authenticated media, which is determined by the packets that are received and able to be decoded and authenticated. The quality of the authenticated media is optimized by allocating the authentication resources unequally across streamed packets based on their relative importance, thereby providing unequal authenticity protection. The effectiveness of this approach is demonstrated through experimental results on different media types (image and video), different compression standards (JPEG, JPEG2000, and H.264), and different channels (wired with packet erasures and wireless with bit errors).

Studying the relation of high-school youth value orientations to the way of spending their free time

The interests and system of individual values is a special domain of human functioning which is mostly influenced by the closest social surrounding. Individuals regard different values with unequal importance and that way value hierarchy is formed. Due to cognitive development the value hierarchy is gradually changing during adolescence. Considering the fact that useful spending of one’s free time has a great influence on an individual’s personality development, his cognitive and will structures and for successful functioning, this paper presents a scientific-research attempt to study the existence of some relation between value orientations and the way s of spending free time. The choice of a research issue is motivated by aspiration for closer insight that would enable greater comprehension, explanation and guiding of educational processes in a contemporary school. 300 high-school students from five Federation towns (Zenica, Travnik, Kakanj, Visoko I Zavidovići) were the respondents. Statistically important relation between high-school student value orientation and both positive and negative spending of free time has been established.

A consensus model of political decision-making

In this paper, a model of political consensus is introduced. Parties try to reach consensus in forming a government. A government is defined as a pair consisting of a winning coalition and a policy supported by this coalition, where a policy consists of policies on given issues. A party evaluates all governments the party belongs to with respect to some criteria. We allow the criteria to be of unequal importance to a party. These criteria concern winning coalitions and policy issues. Parties may be advised to adjust their preferences, i.e., to change their evaluation concerning some government(s) or/and the importance of the criteria, in order to obtain a better political consensus.

Multistreaming of 3-D Scenes With Optimized Transmission and Rendering Scalability

Three-dimensional (3D) graphic scenes require considerable network bandwidth to be transmitted and computing power to be rendered on a user's terminal. Toward high-quality display in real time, we propose a sender-driven mechanism for streaming 3D scenes in a resource-constrained environment. In doing so, objects are encoded into multiresolutions to provide transmission and rendering scalability, and a weighted distortion metric is developed to measure the quality of a scene rendered with multiresolution objects, modeling objects' unequal importance regarding display. To preserve the manipulation independency of multiple objects in data delivery while provide preferential treatment for different objects as well as different layers of each object, transmission of the objects is performed over multiple streams in a partially sequenced and partially reliable fashion. A rate-distortion optimization framework is developed, which determines an optimal level of reliability for every chunk of data in each stream, taking into account the rendering importance of the object, the distortion-rate performance of the data chunks, and the statistics of the network link. Compared with heuristical methods, simulation results show that the proposed framework maximizes the display quality of the scene while minimizing the amount of data that needs to be processed by the client's rendering engine

Joint Source and Channel Coding for 3-D Scene Databases Using Vector Quantization and Embedded Parity Objects

Three-dimensional graphic scenes contain various mesh objects in one geometric space where different objects have potentially unequal importance regarding display. This paper proposes an object-oriented system for efficiently coding and streaming 3-D scene databases in lossy and rate-constrained environments. Vector quantization (VQ) is exploited to code 3-D scene databases into multiresolution hierarchies. For the best distortion-rate performance, adaptive quantization precisions are allocated to different objects and different layers of each object based on a weighted distortion model. Upon transmission, scalably coded objects are delivered in respective packet sequences to preserve their manipulation independency. For packet loss resilience, a plurality of FEC codes are generated as "parity objects" parallel to graphic objects, which protect the graphic objects concurrently and also preferentially in regard to their unequal decoding importance. A rate-distortion optimization framework is then developed, which performs rate allocation between graphic objects and parity objects and generates the parity data properly. We show that, by treating graphic objects jointly and preferentially in source and channel coding while preserving their independencies in transport, the proposed system reduces the receiving distortion of the 3-D database significantly compared to conventional methods.

Consensus reaching in committees

In this paper, we apply a consensus model to decision-making in committees that have to choose one or more alternatives from a set of alternatives. The model does not use a voting rule nor a set of winning coalitions. Every decision maker evaluates each alternative with respect to given criteria. The criteria may be of unequal importance to a decision maker. Decision makers may be advised by a chairman to adjust their preferences, i.e., to change their evaluation of some alternative(s) or/and the importance of the criteria, in order to obtain a better consensus. The consensus result should satisfy constraints concerning the consensus degree and the majority degree. A simple example is presented.

A flexible approach to evaluating soft conditions with unequal preferences in fuzzy databases

A flexible model for evaluating soft query with unequal preferences in fuzzy databases is proposed. We assume that conditions with unequal preferences have an exclusive meaning like in the request “find a holiday accommodation such that big apartments are preferred to high rating hotels.” In this case it is assumed that the aggregator of the soft conditions is an implicit OR. Conversely, conditions with unequal importance have an inclusive meaning, like in the query “find a house to rent that is cheap (most important), big (important), new (fairly important).” In this case the implicit aggregator is an AND. What we propose in this article is to model preferences as modifiers of the semantics of the evaluation function of the conditions. Because the soft conditions are aggregated by an OR, the more a soft condition is preferred, the more its evaluation function tolerates a greater undersatisfaction of the soft condition. The proposed approach is formalized by considering two alternative semantics of the evaluation function: the first semantics defines the evaluation function by means of a generalized fuzzy inclusion measure, and the second one as a generalized similarity measure. These functions are parameterized so that their modification is simply achieved by tuning the functions' parameters. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 665–689, 2007.

Multi-criteria group consensus under linear cost opinion elasticity

Consensus is a pivotal concept in group decision making. Many times, such a consensus is achieved by the experts shifting their opinion towards a point of mutual consent. Such a shift in many cases is the result of laborious negotiations, which escalates the cost of reaching the consensus. Moreover, many times the group decision is multi-criteria oriented in which the experts need to agree on each criterion separately. This paper describes three problems where experts of unequal importance and with a linear cost of changing their opinion (opinion elasticity) consider a single and a multi-criteria decision consensus. These problems achieve a minimum cost consensus without a budget limit. It turns out that the optimal consensus point is at the median opinion for rectilinear cost function and at the weighted average opinion for squared geometric distance calculations. Linear-time algorithms are presented for all cost consensus problems with no budget limits. Proofs, computational complexity and examples are provided for these algorithms.

Error-resilient transmission of resolution-scalable image and video over wireless channels

A new robust transmission strategy for scalable image and video is proposed. To protect the coded bit-stream according to the channel conditions, the proposed scheme exploits the 'progressive by resolution' structure of the scalable code-stream and takes into account the unequal importance as well as the effect of channel errors at different resolution levels towards reconstructing the source. A salient feature of the algorithm is its compatibility for multimedia applications requiring multi-resolution transmission to single or multiple clients. Results show that the proposed algorithm enables considerable gains in terms of subjective and objective image qualities over existing approaches

Control Combinations in Independent Marketing Channels

Continuing the emergent research on plural governance in interfirm relationships, we hypothesized and verified four control combinations, and empirically investigated antecedent factors resultant in the use of each combination. Different from other reported plural governance studies, we focused on control combinations, rather than each composing control mechanism, as the unit of analysis. Our results indicate that control mechanisms employed simultaneously could play roles of unequal importance: some plays the role of primary control, while others secondary control. This finding challenges the implicit assumption of the extant research that all control mechanisms employed are equal in importance. Additionally, questioning the implicit assumption of the extant research that all governance mechanisms are employed to achieve “active” controls, our results suggest that “passive” controls could be warranted under certain theoretical and practical circumstances. Our study also points to the importance of distinguishing “intended” versus “realized” control mechanisms in interfirm control research.

Optimal Allocation for Comparing k Test Treatments to Positive and Negative Control with Unequal Weighting Under A-optimality and MV-optimality

Experiments in real life often involve comparisons of test treatments to more than one control. However, the controls may not always be of equal importance. In this paper we introduce weighted MV optimality criterion and present a detailed study using both weighted A and MV optimality criteria, of the problem of optimally comparing a set of test treatments to two controls (positive and a negative) that are of unequal importance to the experimenter.

Reluctant to change: Self-enhancing responses to diverging performance measures

Although there is extensive evidence that past performance influences the propensity to make changes, research on how decision makers respond to diverging performance measures has been sparse. This paper addresses this gap in an experimental and a field study in which we examine how decision makers respond to the ambiguity introduced by two diverging performance indicators of unequal importance. Both studies suggest that decision makers respond to diverging performance indicators in a self-enhancing manner. Decision makers gave importance to a secondary performance indicator only when it helped them maintain a sense of positive performance, that is, when a secondary performance measure was high and a primary performance measure was low. The results suggest that, in contexts in which decision makers are likely to experience diverging performance indicators, perceptions of success and the associated reluctance to make changes might be more pervasive than is often thought.

Cross-layer conditional retransmission for layered video streaming over cellular networks

In cellular networks, a wireless access network is more error-prone as compared to a wired core network, where burst channel errors often occur because of fading, interference, or lossy handovers. In order to avoid unaccepted quality degradation of video streaming over cellular networks, we propose a cross-layer conditional retransmission scheme based on layered video which is divided into several types with unequal importance by using data partitioning tools. When basic quality-of-service (QoS) guarantees have been provided at the physical layer, the proposed scheme can coordinate mapping of QoS parameters at different layers of communication protocol stack. Considering the unequal importance of different video partitions under the real-time and bandwidth constraints, the proposed scheme first uses the unequal link-layer retransmission to combat channel residual errors in a wireless access network; and then uses the end-to-end transport-layer retransmission to provide enhanced QoS support over cellular networks. The simulation results show that the proposed scheme can effectively improve the perceptual quality of cellular video streaming compared with the traditional conditional retransmission schemes.

A Formal Approach to Handling Conflicts in Multiattribute Group Decision Making

Supporting the decision of a group in engineering design is a challenging and complicated problem when issues like consensus and compromise must be taken into account. In this paper, we present the foundations of the group hypothetical equivalents and inequivalents method and two fundamental extensions making it applicable to new classes of group decision problems. The first extension focuses on updating the formulation to place unequal importance on the preferences of the group members. The formulation presented in this paper allows team leaders to emphasize the input from certain group members based on experience or other factors. The second extension focuses on the theoretical implications of using a general class of aggregation functions. Illustration and validation of the developments are presented using a vehicle selection problem. Data from ten engineering design groups are used to demonstrate the application of the method.