bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulated Cleavages at the West Nile Virus NS4A-2K-NS4B Junctions Play a Major Role in Rearranging Cytoplasmic Membranes and Golgi Trafficking of the NS4A Protein
Authors: Roosendaal Jojanneke , Westaway Edwin G. , Khromykh Alexander , Mackenzie Jason M.
Published: April 2006

A common feature associated with the replication of most RNA viruses is the formation of a unique membrane environment encapsulating the viral replication complex. For their part, flaviviruses are no exception, whereupon infection causes a dramatic rearrangement and induction of unique membrane structures within the cytoplasm of infected cells. These virus-induced membranes, termed paracrystalline arrays, convoluted membranes, and vesicle packets, all appear to have specific functions during replication and are derived from different organelles within the host cell. The aim of this study was to identify which protein(s) specified by the Australian strain of West Nile virus, Kunjin virus (KUNV), are responsible for the dramatic membrane alterations observed during infection. Thus, we have shown using immunolabeling of ultrathin cryosections of transfected cells that expression of the KUNV polyprotein intermediates NS4A-4B and NS2B-3-4A, as well as that of individual NS4A proteins with and without the C-terminal transmembrane domain 2K, resulted in different degrees of rearrangement of cytoplasmic membranes. The formation of the membrane structures characteristic for virus infection required coexpression of an NS4A-NS4B cassette with the viral protease NS2B-3pro which was shown to be essential for the release of the individual NS4A and NS4B proteins. Individual expression of NS4A protein retaining the C-terminal transmembrane domain 2K resulted in the induction of membrane rearrangements most resembling virus-induced structures, while removal of the 2K domain led to a less profound membrane rearrangement but resulted in the redistribution of the NS4A protein to the Golgi apparatus. The results show that cleavage of the KUNV polyprotein NS4A-4B by the viral protease is the key initiation event in the induction of membrane rearrangement and that the NS4A protein intermediate containing the uncleaved C-terminal transmembrane domain plays an essential role in these membrane rearrangements.
Generation of Infectious Hepatitis C Virus in Immortalized Human Hepatocytes
Authors: Kanda Tatsuo , Basu Arnab , Steele Robert , Wakita Takaji , Ryerse Jan S. , Ray Ranjit , Ray Ratna B.
Published: April 2006

Progress in understanding hepatitis C virus (HCV) biology has remained a challenge due to the lack of an efficient cell culture system for virus growth. In this study, we examined HCV core protein-mediated immortalized human hepatocytes (IHH) for growth of HCV. In vitro-transcribed full-length RNA from HCV genotype 1a (clone H77) was introduced into IHH by electroporation. Reverse transcription-PCR of cellular RNA isolated from HCV genome-transfected IHH suggested that viral RNA replication occurred. IHH transfected with the full-length HCV genome also displayed viral protein expression by indirect immunofluorescence. In contrast, cells transfected with polymerase-defective HCV (H77/GND) RNA as a negative control did not exhibit expression of the viral genome. Immunogold labeling demonstrated localization of E1 protein in the rough endoplasmic reticulum of RNA-transfected IHH. Virus-like particles of ∼50 nm were observed in the cytoplasm. After being inoculated with culture media of cells transfected with the full-length HCV genome, naïve IHH displayed NS5a protein expression in a dilution-dependent manner, but expression of NS5a was inhibited by prior incubation of culture medium with HCV-infected patient sera. NS5a-positive immunofluorescence of cell culture media of IHH transfected with full-length H77 RNA yielded ∼4.5 × 10
4
to 1 × 10
5
focus-forming units/ml. A similar level of virus growth was observed upon transfection of RNA from HCV genotype 2a (JFH1) into IHH. Taken together, our results suggest that IHH support HCV genome replication and virus assembly.
COMPETITION OF LANGUAGES AND THEIR HAMMING DISTANCE
Authors: TEŞILEANU TIBERIU , MEYER-ORTMANNS HILDEGARD
Published: April 2006

We consider the spreading and competition of languages that are spoken by a population of individuals. The individuals can change their mother tongue during their lifespan, pass on their language to their offspring and finally die. The languages are described by bitstrings, their mutual difference is expressed in terms of their Hamming distance. Language evolution is determined by mutation and adaptation rates. In particular we consider the case where the replacement of a language by another one is determined by their mutual Hamming distance. As a function of the mutation rate we find a sharp transition between a scenario with one dominant language and fragmentation into many language clusters. The transition is also reflected in the Hamming distance between the two languages with the largest and second to largest number of speakers. We also consider the case where the population is localized on a square lattice and the interaction of individuals is restricted to a certain geometrical domain. Here it is again the Hamming distance that plays an essential role in the final fate of a language of either surviving or being extinct.
MILITARY VEHICLE CLASSIFICATION VIA ACOUSTIC AND SEISMIC SIGNALS USING STATISTICAL LEARNING METHODS
Authors: XIAO HANGUANG , CAI CONGZHONG , CHEN YUZONG
Published: April 2006

It is a difficult and important task to classify the types of military vehicles using the acoustic and seismic signals generated by military vehicles. For improving the classification accuracy and reducing the computing time and memory size, we investigated different pre-processing technology, feature extraction and selection methods. Short Time Fourier Transform (STFT) was employed for feature extraction. Genetic Algorithms (GA) and Principal Component Analysis (PCA) were used for feature selection and extraction further. A new feature vector construction method was proposed by uniting PCA and another feature selection method. K-Nearest Neighbor Classifier (KNN) and Support Vector Machines (SVM) were used for classification. The experimental results showed the accuracies of KNN and SVM were affected obviously by the window size which was used to frame the time series of the acoustic and seismic signals. The classification results indicated the performance of SVM was superior to that of KNN. The comparison of the four feature selection and extraction methods showed the proposed method is a simple, none time-consuming, and reliable technique for feature selection and helps the classifier SVM to achieve more better results than solely using PCA, GA, or combination.
CELLULAR NEURAL NETWORK MODELS OF GROWTH AND IMMUNE OF EFFECTOR CELLS RESPONSE TO CANCER
Authors: SU YONGMEI , MIN LEQUAN
Published: April 2006

Four reaction-diffusion cellular neural network (R-D CNN) models are set up based on the differential equation models for the growths of effector cells and cancer cells, and the model of the immune response to cancer proposed by Allison et al. The CNN models have different reaction-diffusion coefficients and coupling parameters. The R-D CNN models may provide possible quantitative interpretations, and are good in agreement with the in vitro experiment data reported by Allison et al.
NATIONAL SYSTEMS OF INNOVATION AND TECHNOLOGICAL DIFFERENTIATION: A MULTI-COUNTRY MODEL
Authors: RIBEIRO LEONARDO C. , RUIZ RICARDO M. , ALBUQUERQUE EDUARDO M. , BERNARDES AMÉRICO T.
Published: April 2006

Science and technology have a fundamental role in the economic development. Although this statement is generally well accepted, the internal mechanisms which are responsible for these interactions are not clear. In the last decade, dealing with this problem, many models have been proposed. In this paper, we introduce a model that creates an artificial world economy that is a network of countries. Each country has its own national system of innovation and the interactions between countries are given by functions that connect the competitiveness of their prices and their technological capabilities. Starting from different configurations, the artificial world economy self-organizes itself and creates a hierarchies of countries.
MULTISPIN CODING TECHNIQUE FOR NONEQUILIBRIUM REWEIGHTING
Authors: LEE HWEE KUAN , OKABE YUTAKA
Published: April 2006

We present the multispin coding for the nonequilibrium reweighting method of the Monte Carlo simulation, that was developed by the present authors. As an illustration, we treat the driven diffusive lattice gas model. We use the multispin coding technique both for the spin update and for the calculation of the histogram of incremental weights, which is needed in the calculation of nonequilibrium reweighting. All the operations are executed by the bitwise logical commands.
SINGLE WALL BAMBOO SHAPED CARBON NANOTUBE: A MOLECULAR DYNAMICS AND ELECTRONIC STUDY
Authors: MALCIOĞLU OSMAN BARIŞ , TAŞCI EMRE , ERKOÇ ŞAKİR
Published: April 2006

Thermal stability and molecular electronic properties of a single walled, bamboo shaped carbon nanotube has been investigated. Molecular dynamics method is applied to investigate thermal stability, and electronic properties are calculated at the Extended Huckel level. Although bamboo shaped carbon nanotubes observed in experimental literature are multi-walled, it is shown that the suggested structural model in this work, which is single-walled, is also both thermodynamically and energetically stable. Bamboo shape of the model investigated is due to periodical coronene-like spacers. The resultant structure is compartmented, having geometrical aberrations in the vicinity of spacers. There is no degradation in the average coordination number. The geometrical aberrations in the vicinity of spacers is due to curvature induced by the pentagons of the resultant geometry.
CONFORMATION AND PHASE TRANSITION OF POLY-GLUTAMINE
Authors: GÖKOĞLU GÖKHAN , ÇELİK TARIK
Published: April 2006

In order to provide insights into the misfolding mechanism and the subsequent aggregate formation which cause what are known as the neurodegenerative polyglutamine diseases, we have simulated a 10-residue polyglutamine (poly-Q) chain in vacuum and in solvent by multicanonical method, which enabled us to study the system in a wide temperature range and discuss thermodynamic properties. It is understood that the system in vacuum shows two phase transitions, first of them occur at high temperature that is the well-known helix-coil transition and the second one is a solid-solid transition. However, the poly-Q chain in solvent is in a random coil state at higher temperatures, goes through a conformational change at T = 200 K and assumes predominantly a mixture of anti-parallel β-sheet and α-helix structures at low temperatures. One-residue glutamine dipeptide is also simulated and low-energy stable conformations are identified.
SIMULATION OF MAD COW DISEASE PROPAGATION
Authors: MAGDOŃ-MAKSYMOWICZ M. S. , MAKSYMOWICZ A. Z. , GOŁDASZ J.
Published: April 2006

Computer simulation of dynamic of BSE disease is presented. Both vertical (to baby) and horizontal (to neighbor) mechanisms of the disease spread are considered. The game takes place on a two-dimensional square lattice Nx×Ny = 1000×1000 with initial population randomly distributed on the net. The disease may be introduced either with the initial population or by a spontaneous development of BSE in an item, at a small frequency. Main results show a critical probability of the BSE transmission above which the disease is present in the population. This value is vulnerable to possible spatial clustering of the population and it also depends on the mechanism responsible for the disease onset, evolution and propagation. A threshold birth rate below which the population is extinct is seen. Above this threshold the population is disease free at equilibrium until another birth rate value is reached when the disease is present in population. For typical model parameters used for the simulation, which may correspond to the mad cow disease, we are close to the BSE-free case.
MONTE CARLO SIMULATIONS OF THE INSIDE INTRON RECOMBINATION
Authors: CEBRAT STANISŁAW , PȨKALSKI ANDRZEJ , SCHARF FABIAN
Published: April 2006

Biological genomes are divided into coding and non-coding regions. Introns are non-coding parts within genes, while the remaining non-coding parts are intergenic sequences. To study evolutionary significance of the inside intron recombination we have used two models based on the Monte Carlo method. In our computer simulations we have implemented the internal structure of genes by declaring the probability of recombination between exons. One situation when inside intron recombination is advantageous is recovering functional genes by combining proper exons dispersed in the genetic pool of the population after a long period without selection for the function of the gene. Populations have to pass through the bottleneck, then. These events are rather rare and we have expected that there should be other phenomena giving profits from the inside intron recombination. In fact we have found that inside intron recombination is advantageous only in the case when after recombination, besides the recombinant forms, parental haplotypes are available and selection is set already on gametes.
THE WORKING OF CIRCUIT BREAKERS WITHIN PERCOLATION MODELS FOR FINANCIAL MARKETS
Authors: EHRENSTEIN GUDRUN , WESTERHOFF FRANK
Published: April 2006

We use a modified Cont–Bouchaud model to explore the effectiveness of trading breaks. The modifications include that the trading activity of the market participants depends positively on historical volatility and that the orders of the agents are conditioned on the observed mispricing. Trading breaks, also called circuit breakers, interrupt the trading process when prices are about to exceed a pre-specified limit. We find that trading breaks are a useful instrument to stabilize financial markets. In particular, trading breaks may reduce price volatility and deviations from fundamentals.
A SIMPLE FORECASTING GAME
Authors: ANDRECUT M.
Published: April 2006

We consider a population of Boolean agents playing a simple forecasting game, in which the goal of each agent is to give a correct forecast of the future state of its neighbors. The numerical results show that by using a simple inductive learning algorithm the agents are able to accurately achive the goal of the game. However, this remarkable performance has an unexpected consequence: by learning to forecast the future, the agents dynamics freezes up at the end of the game; the only way to regain their dynamics is to forget what they have learned.
BANDGAP NARROWING IN NANO-WIRES
Authors: NOZARI KOUROSH , MADADI MAHYAR
Published: April 2006

In this paper we consider two different geometry of quasi one-dimensional semiconductors and calculate their exchange-correlation induced bandgap renormalization (BGR) as a function of the electron-hole plasma density and quantum wire width. Based on different fabrication scheme, we define suitable external confinement potential and then leading-order GW dynamical screening approximation is used in the calculation by treating electron–electron Coulomb interaction and electron-optical phonon interaction. Using a numerical scheme, screened Coulomb potential, probability of different states, profile of charge density and the values of the renormalized gap energy are calculated and the effects of variation of confinement potential width and temperature are studied.
COOPERATION AND DEFECTION IN GHETTO
Authors: KUŁAKOWSKI KRZYSZTOF
Published: April 2006

We consider ghetto as a community of people ruled against their will by an external power. Members of the community feel that their laws are broken. However, attempts to leave ghetto makes their situation worse. We discuss the relation of the ghetto inhabitants to the ruling power in context of their needs, organized according to the Maslow hierarchy. Decisions how to satisfy successive needs are undertaken in cooperation with or defection the ruling power. This issue allows to construct the tree of decisions and to adopt the pruning technique from the game theory. Dynamics of decisions can be described within the formalism of fundamental equations. The result is that the strategy of defection is stabilized by the estimated payoff.
DESIGN OF A MULTICODE BI-PHASE ENCODER FOR DATA TRANSMISSION
Authors: AL-ALAWI RAIDA , AL-SAMMAK A. J.
Published: April 2006

In this paper, we present a versatile Multicode Bi-Phase Encoder (MBPE) circuit capable of encoding five different Bi-Phase line codes, namely: Bi-Phase-Level (Bi-Φ-L), Bi-Phase-Mark (Bi-Φ-M), Bi-Phase-Space (Bi-Φ-S), Differential Manchester (DM) and Inverse Differential Manchester (IDM) codes. The design methodology is based on a new definition of these codes in terms of encoding rules and state diagrams, instead of the traditional way of representing them in terms of their bit transition. The operation mode of the MBPE is set by three selection lines, which can be either hardware or software controlled. This will facilitate the process of altering the data transmission protocol without the need of changing the encoder hardware. The functionality and design of the MBPE is outlined. VHDL has been used to describe the behavior of the MBPE whose operation was verified using the ModelSim XE II Simulation tools. Implementation and testing of the MBPE on XILINX Spartan-II FPGA showed that the MBPE circuit is capable of encoding NRZ data into any of the five codes.
DESIGNING QUADRATURE MIRROR FILTER BANKS USING STEEPEST DESCENT METHOD
Authors: SAHU O. P. , SONI M. K. , TALWAR I. M.
Published: April 2006

This paper proposes a new technique for the design of quadrature mirror filter (QMF) banks by exploiting steepest descent method. The design problem is formulated to minimize an objective function, which is a weighted sum of the pass band error and stop band residual energy of the low pass analysis filter of the QMF bank. The minimization has been carried out gradually by respective optimum step lengths in the corresponding steepest descent directions of a linear combination of the objective function and square of the reconstruction error of the QMF bank at the quadrature frequency by optimizing the filter tap weights. The design results show that the proposed method gives a comparable performance to the already existing methods.
64-BIT PIPELINE CARRY LOOKAHEAD ADDER USING ALL-N-TRANSISTOR TSPC LOGICS
Authors: CHENG KUO-HSING , CHENG SHUN-WEN , LEE WEN-SHIUAN
Published: April 2006

This paper proposes two improved circuit techniques of True Single-Phase Clocking (TSPC) logic, which called Nonfull Swing TSPC (NSTSPC) and All-N-TSPC (ANTSPC). The voltage of internal node of the NSTSPC is not full swing; it saves partial dynamic power dissipation. And the ANTSPC uses NMOS transistors to replace PMOS transistors, the output loading of Φ-section is therefore reduced and a higher layout density is obtained. Through postlayout simulation comparisons between number of stacked MOS transistors and delay time, and supply voltage vs maximum frequency, the proposed NSTSPC and ANTSPC circuits show better operation speed and power performance than the conventional TSPC circuit. Finally, the new TSPC circuits are applied to a 64-bit hierarchical pipeline Carry Lookahead Adder (CLA), which based on TSMC 0.35 μm CMOS process technology. By using the techniques of NSTSPC and ANTSPC alternately, the 64-bit CLA is successfully implemented as a pipelined structure. The results of post-layout simulation show that the 64-bit CLA can be operated on 1.25 GHz clock frequency and its power/maximal frequency ratio is 151.4 μW/MHz.
INFLUENCE OF INPUT/OUTPUT OPERATIONS ON PROCESSOR PERFORMANCE
Authors: RODRÍGUEZ CORRAL JOSE MARIA , BALCELLS ANTON CIVIT , MORENO GABRIEL JIMENEZ , SEVILLANO RAMOS JOSE LUIS , ESTEVEZ ARTURO MORGADO
Published: April 2006

Nowadays, computers are frequently equipped with peripherals that transfer great amounts of data between them and the system memory using direct memory access techniques (i.e., digital cameras, high speed networks, …). Those peripherals prevent the processor from accessing system memory for significant periods of time (i.e., while they are communicating with system memory in order to send or receive data blocks). In this paper we study the negative effects that I/O operations from computer peripherals have on processor performance. With the help of a set of routines (SMPL) used to make discrete event simulators, we have developed a configurable software that simulates a computer processor and main memory as well as the I/O scenarios where the peripherals operate. This software has been used to analyze the performance of four different processors in four I/O scenarios: video capture, video capture and playback, high speed network, and serial transmission.
PERFORMANCE ANALYSIS OF MULTICARRIER CDMA SYSTEM BASED ON COMPLEX WAVELET PACKET AND SPACE–TIME BLOCK CODES IN RAYLEIGH FADING CHANNEL
Authors: YU XIANGBIN , ZHANG XIAODONG , BI GUANGGUO
Published: April 2006

On the basis of analyzing the principle of multicarrier CDMA (MC-CDMA) technique and space–time coding technique, using the optimized complex wavelet packet as multicarrier modulation, a novel MC-CDMA system based on complex wavelet packet and space–time block codes is proposed. The bit error rate (BER) performance of the system is investigated in Rayleigh fading channel, and the corresponding BER expression is derived in detail. The system can overcome the decrease of spectrum efficiency of conventional MC-CDMA due to inserting cyclic prefix (CP). Moreover, the application of space–time coding technique strengthens the capability against fading channel significantly and perfects the system performance. Theoretical analysis shows that the proposed system with 2-transmitter antenna and 2-receiver antenna space–time block codes performs four times better than the single-antenna MC-CDMA system based on complex wavelet packet (CWP-MC-CDMA); the same conclusion is also reached by the simulation results in fading channel. As a result, the performance of the proposed CWP-MC-CDMA system outperforms a conventional MC-CDMA system based on DFT, it is close or superior to that of the conventional MC-CDMA with CP. Especially, the CWP-MC-CDMA system with space–time coding has superior ability to combat spatial fading and multi-access interference, and it slightly outperforms conventional MC-CDMA with CP and space–time coding.
MODERN FLOORPLANNING WITH BOUNDARY AND FIXED-OUTLINE CONSTRAINTS VIA GENETIC CLUSTERING ALGORITHM
Authors: LIN CHANG-TZU , CHEN DE-SHENG , WANG YI-WEN
Published: April 2006

Typical floorplanning problem concerns a series of objectives, such as area, wirelength and routability, etc., without any specific constraint in a free-outline style. Entering SOC era; however, modern floorplanning takes more care of providing extra options, such as boundary constraint for I/O connections and fixed-outline constraint for hierarchical designs. It has been empirically shown that one of the modern constraints extremely restricts the solution space; that is, a large number of randomly generated floorplans might be infeasible. This paper tackles modern floorplanning with both boundary and fixed-outline constraints. A novel genetic clustering algorithm was proposed to guarantee to produce slicing floorplans with satisfying boundary constraint. By analyzing the properties of the slicing floorplan, the algorithm is effective to cluster the boundary-constrained modules into four constrained sub-floorplans. Afterward, the four sub-floorplans were combined to satisfy the boundary constraint. We then extend the algorithm with minor modification to enable the slicing floorplans with boundary constraint to be gradually fit into the desirable fixed outline. The methods were verified by using the MCNC and GSRC benchmarks, and the empirical results show that our methods can obtain promising solutions using short time.
ON THE REDUCTION OF INTERCONNECT EFFECTS IN DEEP SUBMICRON IMPLEMENTATIONS OF DIGITAL MULTIPLICATION ARCHITECTURES
Authors: MOKRIAN PEDRAM , AHMADI MAJID , JULLIEN GRAHAM
Published: April 2006

The conventional trend in algorithm implementation has been the reliance on advancements in process technology in order to satisfy the ever-increasing demand for high-speed and low power processors, and computational systems. As current device technology approaches sub-100 nm minimum device size, not only does the device geometry decrease, but switching times and operating voltages also scale down. These gains come at the expense of increased layout complexity, and a greater susceptibility to parasitic effects in the interconnections. In this paper we briefly overview the challenges that digital arithmetic designers will have to face in the imminent future, and we provide suggestions on algorithmic measures which may be taken in order to overcome some of these challenges. To illustrate our point, we will present an analysis of a digital multiplication algorithm, which is predicted to outperform currently preferred architectures for future technologies. We then apply the algorithm to form a multiplier architecture that alleviates many of the problems associated with interconnect scaling; in addition, our new architecture allows for simple variable precision reconfiguration.
NOVEL FLOATING INDUCTANCE AND FDNR SIMULATORS EMPLOYING CCII+s
Authors: YUCE ERKAN , CICEKOGLU OGUZHAN , MINAEI SHAHRAM
Published: April 2006

In this paper, a floating inductance and frequency-dependent negative resistance (FDNR) depending on the passive element selection is presented. The proposed circuit employs only plus-type second-generation current conveyors (CCII+s) as active elements, together with two resistors and two capacitors for realizing floating inductance and FDNR. Both of the capacitors in the floating inductance realization are grounded. Also, electronically tunable floating FDNR is obtained with the proposed circuit. The nonideality effects of the current conveyors on the proposed circuit are given. The proposed circuit is used in a low-pass ladder filter, and simulated with SPICE to exhibit its performance.
MODULO (2p ± 1) MULTIPLIERS USING A THREE-OPERAND MODULAR SIGNED-DIGIT ADDITION ALGORITHM
Authors: WEI SHUGANG , SHIMIZU KENSUKE
Published: April 2006

In this paper, a new three-operand modulo (2p ± 1) addition is implemented by performing a carry-save addition and a two-operand modular addition based on the p-digit radix-two signed-digit (SD) number system. Thus, the delay time of the three-operand modular adder is independent of the word length of the operands. A modulo (2p ± 1) multiplier is constructed as a ternary tree of the three-operand modular SD adders, and the modular multiplication time is proportional to log 3 p. When a serial modular multiplier is constructed using the three-operand modular SD adder, two modular partial products can be added to the sum at the same time. Two kinds of Booth recoding methods are also proposed to reduce the partial products from p to p/2. Therefore, the performance of a parallel modular multiplier can be modified by reducing half of the modular SD adders in the adder tree. For a serial modular multiplication, two partial products are generated from two Booth recoders and added to the sum by using one three-operand modular SD adder, so that the speed of the modular multiplication is three times as fast as the speed without using the three-operand modular SD adder and the Booth recoding method. A very large-scale integration (VLSI) implementation method by VHDL is also discussed. The design and simulation results show that high-speed modular multipliers can be obtained by the algorithms presented.
ON ČERNIKOV-BY-NILPOTENT GROUPS
Authors: LEMNOUAR NOUI
Published: April 2006

In this paper, we study the class (Ω, ∞) of groups whose every infinite subset contains two distinct elements generating an Ω-group where Ω is either the class of Černikov groups, or the class of Černikov-by-nilpotent groups and we deduce some characterizations of finite-by-nilpotent groups.
COMPARISON OF FINITE VOLUME AND FINITE DIFFERENCE METHODS AND APPLICATION
Authors: FAURE S. , PHAM D. , TEMAM R.
Published: April 2006

In this article, we consider finite volume methods based on a non-uniform grid. Finite volume methods are compared to finite difference methods based on a related grid. As an application, various convergence results are proved for the finite volume function spaces and for some model elliptic and parabolic boundary value problems using these discretization spaces.
ON THE OSEEN PROBLEM IN THREE-DIMENSIONAL EXTERIOR DOMAINS
Authors: AMROUCHE CHÉRIF , RAZAFISON ULRICH
Published: April 2006

In this paper, we prove existence and uniqueness results for the Oseen problem in exterior domains of ℝ3. To prescribe the growth or decay of functions at infinity, we set the problem in weighted Sobolev spaces. The analysis relies on a Lp-theory for any real p such that 1 < p < ∞.
GLOBAL MULTIDIMENSIONAL SHOCK WAVE FOR THE STEADY SUPERSONIC FLOW PAST A THREE-DIMENSIONAL CURVED CONE
Authors: XIN ZHOUPING , YIN HUICHENG
Published: April 2006

In this paper, we establish the global existence and stability of a multidimensional conic shock wave for three-dimensional steady supersonic flow past an infinite cone. The flow is assumed to be hypersonic and described by a steady potential flow equation. Under an appropriate boundary condition on the curved cone, we show that a pointed shock attached at the vertex of the cone will exist globally in the whole space.
AN ALTERNATIVE APPROACH TO FIRMS' EVALUATION: EXPERT SYSTEMS AND FUZZY LOGIC
Authors: MAGNI CARLO ALBERTO , MALAGOLI STEFANO , MASTROLEO GIOVANNI
Published: April 2006

Discounted cash flow techniques are the generally accepted methods for valuing firms. Such methods do not provide explicit acknowledgment of the value determinants and overlook their interrelations. This paper proposes a different method of firm valuation based on fuzzy logic and expert systems. It does represent a conceptual transposition of discounted cash flow techniques but, unlike the latter, it takes explicit account of quantitative and qualitative variables and their mutual integration. Financial, strategic and business aspects are considered by focusing on 29 value drivers that are combined together via "if–then" rules. The output of the system is a real number in the interval [0, 1], which represents the value-creation power of the firm. To corroborate the model a sensitivity analysis is conducted. The system may be used for rating and ranking firms as well as for assessing the impact of managers' decisions on value creation and as a tool of corporate governance.
A DECISION TREE-BASED CLASSIFICATION APPROACH TO RULE EXTRACTION FOR SECURITY ANALYSIS
Authors: REN N. , ZARGHAM M. , RAHIMI S.
Published: April 2006

Stock selection rules are extensively utilized as the guideline to construct high performance stock portfolios. However, the predictive performance of the rules developed by some economic experts in the past has decreased dramatically for the current stock market. In this paper, C4.5 decision tree classification method was adopted to construct a model for stock prediction based on the fundamental stock data, from which a set of stock selection rules was derived. The experimental results showed that the generated rules have exceptional predictive performance. Moreover, it also demonstrated that the C4.5 decision tree classification model can work efficiently on the high noise stock data domain.
NETWORK PERFORMANCE IMPACTS ON OPERATORS IN SAFETY-CRITICAL SYSTEMS
Authors: BAYRAK TUNCAY , GRABOWSKI MARTHA R.
Published: April 2006

Safety-critical wide area networks are comprised of human and technical elements cooperatively performing tasks in a safety-critical setting. In such settings, both human and technical dimensions are critical in performance evaluation. It is the relationships between changes in network performance and their impacts on human operator performance with safety-critical wide area networks that we investigate in this research. The paper begins by examining the theoretical background for this research, and then describes the research model. It was found that decreases in network reliability were associated with expected degradations in operator satisfaction, operator confidence, and increases in operator workload. Likewise, it was found that an increased number of network tasks processed was associated with a decrease in operator accuracy and decreased operator communication. The results of this study suggest that understanding the impact of the network performance on human performance is important in safety-critical settings employing wide-area networks.
ENHANCED INTERACTIVE SATISFYING OPTIMIZATION APPROACH TO MULTIPLE OBJECTIVE OPTIMIZATION WITH PREEMPTIVE PRIORITIES
Authors: HU CHAOFANG , LI SHAOYUAN
Published: April 2006

This paper proposes an enhanced interactive satisfying optimization method based on goal programming for the multiple objective optimization problem with preemptive priorities. Based on the previous method, the approach presented makes the higher priority achieve the higher satisfying degree. For three fuzzy relations of the objective functions, the corresponding optimization models are proposed. Not only can satisfying results for all the objectives be acquired, but the preemptive priority requirement can also be simultaneously actualized. The balance between optimization and priorities is realized. We demonstrate the power of this proposed method by illustrative examples.
N-SITE: A DISTRIBUTED CONSENSUS BUILDING AND NEGOTIATION SUPPORT SYSTEM
Authors: TAVANA MADJID , KENNEDY DENNIS T.
Published: April 2006

This paper presents N-Site, a distributed consensus building and negotiation support system, which is used to provide geographically dispersed teams with agile access to a Web-based group decision support system. Four teams located in France, Mexico, the Ukraine, and the United States participated in the N-Site project. Each team was required to research the problem using the World Wide Web (WWW). With this background, each team identified opportunities, threats and alternatives as a basis for developing a response to the Cuban Missile Crisis that confronted President Kennedy in October 1962. The strategic assessment model (SAM) (M. Tavana, J. Multi-Criteria Decision Anal.11 (2002) 75–96; M. Tavana and S. Banerjee, Decision Sci.26 (1995) 119–143.) was used by each team to choose a strategy that best fit the team's perspective. SAM and WWW enabled the teams to evaluate strategic alternatives and build consensus based on a series of intuitive and analytical methods including environmental scanning, the analytic hierarchy process (AHP) and subjective probabilities. The WWW was used to achieve interaction among the international teams as they attempted to negotiate a decision framework and select a diplomatic response. The project was assessed with a Web-distributed survey instrument. This use of the WWW has implications for international diplomacy as well as global business.
PREDICTING GLOBAL INTERNET GROWTH USING AUGMENTED DIFFUSION, FUZZY REGRESSION AND NEURAL NETWORK MODELS
Authors: BAGCHI KALLOL , MUKHOPADHYAY SOMNATH
Published: April 2006

Quantitative models explaining and forecasting the growth of new technology like the Internet in global business operation appear infrequently in the literature. This paper introduces two artificial intelligence (AI) models such as the neural network and fuzzy regression along with an augmented diffusion model to study and predict the Internet growth in several OECD nations. First, a linear version of an augmented diffusion model is designed. An augmented diffusion model is constructed by including an economic indicator, gross domestic product per capita, into the model. In the next step, two soft AI models are calibrated from the augmented diffusion model. Performance measures of predictions from these models on new samples show that these soft models provide improved forecast accuracy over the augmented diffusion model. The results confirm the major contribution of this research in predicting global Internet growth.
A CASE STUDY IN PARTICIPATORY PRIORITY SETTING FOR A SCANDINAVIAN RESEARCH PROGRAM
Authors: SALO AHTI , LIESIÖ JUUSO
Published: April 2006

Continuing attempts to align science and technology policies with industrial and societal needs have aroused interest in the determination of research priorities. In this paper, we report a case study where leading experts from industry and public administration were assisted by multicriteria decision analysis in the planning of a collaborative research program for Scandinavian forestry and forest industries. We also address processual and methodological challenges in the deployment of multicriteria methods, and argue that such methods can contribute to the quality of decision support processes in related contexts.
YINYANG BIPOLAR FUZZY SETS AND FUZZY EQUILIBRIUM RELATIONS: FOR CLUSTERING, OPTIMIZATION, AND GLOBAL REGULATION
Authors: ZHANG WEN-RAN
Published: April 2006

Based on the notions of bipolar lattices and L-sets, YinYang bipolar fuzzy sets and fuzzy equilibrium relations are presented for bipolar clustering, optimization, and global regulation. While a bipolar L-set is defined as a bipolar equilibrium function L that maps a bipolar object set X over an arbitrary bipolar lattice B as L:X ⇒ B, this work focuses on the unit square lattice B F = [-1, 0] × [0, 1]. A strong or weak bipolar fuzzy equilibrium relation in a bipolar set X is then defined as a reflexive, symmetric, and bipolar interactive (or transitive) fuzzy relation μR: X ⇒ B F . Three types of bipolar α-level sets are presented for bipolar defuzzification and depolarization. It is shown that a fuzzy equilibrium relation is a non-linear bipolar generalization and/or fusion of multiple similarity relations, which induces disjoint or joint bipolar fuzzy subsets including quasi-coalition, conflict, and harmony sets. Equilibrium energy and stability analysis can then be utilized on different clusters for optimization and global regulation purposes. Thus, this work provides a unified approach to truth, fuzziness, and polarity and leads to a holistic theory for cognitive-map-based visualization, optimization, decision, global regulation, and coordination. Basic concepts are illustrated with a simulation in macroeconomics.
THE EVALUATION OF INFORMATION TECHNOLOGY PROJECTS: A FUZZY MULTICRITERIA DECISION-MAKING APPROACH
Authors: THOMAIDIS NIKOLAOS S. , NIKITAKOS NIKITAS , DOUNIAS GEORGIOS D.
Published: April 2006

This paper presents a fuzzy set-based approach to the evaluation of information technology (IT) projects. We assume a multi-criteria decision-making framework, where sets of general and domain-specific criteria are used to judge the relative performance of alternative technologies. The methodology was originally developed for DIAS.net, an EU project aiming at the development of the Information Society in insular and isolated regions of Europe. In this paper, we present many aspects of our evaluation framework, including the synthesis of evaluation teams, the assessment of the importance of criteria, the evaluation of the performance of the alternatives and the final ranking and selection of projects. The methodology presented has the innovative feature of embodying techniques of fuzzy sets theory into the classical multi-criteria decision analysis. This combination enables us to handle efficiently the subjectiveness that often characterizes expert judgements on a decision problem. Fuzzy linguistic terms, such as "poor," "fair," "very important," etc. are proposed for assessing the relative merit of alternatives and criteria. The paper concludes by exploring the potentiality of the above methodology in providing a flexible and robust IT evaluation framework.
DECISION TRAPS AND COMPETENCE DYNAMICS IN CHANGEABLE SPACES
Authors: YU P. L. , CHIANGLIN C. Y.
Published: April 2006

There are many parameters in challenging decision problems, including the alternatives, the criteria, resources, the perception of decision problems, decision makers and their psychological states, information inputs from the environment, and self-suggestion, etc. At any moment of time, some of these parameters can catch our attention, called alerted parameters; some cannot, called unalerted parameters. Some parameters are visible, some are invisible. In addition, the parameters themselves can vary over certain ranges or domains. All of these make challenging decision problems very complex. We call this kind of problems as decision problems with changeable spaces (parameters).

We may focus on certain parameters with certain assumed values to find an "optimal" solution, which may lead to solve wrong problem with bad solution. Quite often, our focus may be just a small part of what we know, or just a part of what we are most familiar with. We may often neglect what we are not familiar with, and pay no attention to what we do not know. As a consequence, we may see just a small part of the problem domain (including all parameters and their possible variations over time). The portion (of the problem domain) that we cannot see is our decision blind. Suppose our alerted domain (those parameters and their variations that are currently under our consideration) to be fixed in only a small part of the problem domains. Then very likely we could end up with a serious mistake. This situation is known as decision trap.

In this article, we will introduce a systematic scheme, based on habitual domain theory, to help us reduce decision blinds and avoid decision traps so that we could make decision with good quality. Then we will also introduce the concept of competence set analysis to help us cope with challenging decision problems. This including: (i) how to effectively expand our competence (resources, skill, know-how, information, ideas, effort, etc.) as to solve a given problem effectively; and (ii) given a set of competence, how to maximize its value by solving a set of value added problems. Furthermore, we will introduce innovation dynamics which describe the dynamics of how to solve a set of problems with our existent or acquired competence (to relieve the pains or frustrations of "certain customers or decision makers" at certain situations) as to create value, and how to distribute this created value so that we can continuously expand out competence set to solve more challenging problems and create more value.
The effect of an acute elevation of NEFA concentrations on glucagon-stimulated hepatic glucose output
Authors: Everett-Grueter Carrie , Edgerton Dale S. , Donahue E. Patrick , Vaughan Suzan , Chu Chang An , Sindelar Dana K. , Cherrington Alan D.
Published: April 2006

To determine the effect of nonesterified fatty acids (NEFA) on glucagon action, glucagon was infused intraportally (1.65 ng·min−1·kg−1) for 3 h into 18-h-fasted, pancreatic-clamped conscious dogs in the presence [NEFA + glucagon (GGN)] or absence (GGN) of peripheral Intralipid plus heparin infusion. Additionally, hyperglycemic (HG), hyperglycemic-hyperlipidemic (NEFA + HG), and glycerol plus glucagon (GLYC + GGN) controls were studied. Arterial plasma glucagon concentrations rose equally in GGN, NEFA + GGN, and GLYC + GGN but remained basal in hyperglycemic controls. Peripheral infusions of Intralipid and heparin increased arterial plasma NEFA concentrations equally in NEFA + GGN and NEFA + HG and did not change in other protocols. After 15 min, glucagon infusion resulted in a rapid, brief increase in net hepatic glycogenolysis (NHGLY, mg·min−1·kg−1) of ∼6.0 in GGN and GLYC + GGN but only increased by 3.8 ± 1.3 in NEFA + GGN. Thus increases in NHGLY, and consequently net hepatic glucose output (NHGO), were blunted by 40%, with no difference between the groups in the last 2.5 h of the study. NHGO and NHGLY did not significantly change in HG and NEFA + HG. Net hepatic gluconeogenic flux did not change in GGN, GLYC + GGN, or HG. However, Intralipid and heparin infusion resulted in similar increases in net hepatic gluconeogenic flux in NEFA + GGN and NEFA + HG. Thus elevated NEFA limit the initial increase in glucagon-stimulated HGO by blunting glycogenolysis, without having any effect on the gluconeogenic or glycogenolytic contributions or NHGO thereafter.
Altered cardiac fatty acid composition and utilization following dexamethasone-induced insulin resistance
Authors: Qi Dake , An Ding , Kewalramani Girish , Qi Yadan , Pulinilkunnil Thomas , Abrahani Ashraf , Al-Atar Usama , Ghosh Sanjoy , Wambolt Richard B. , Allard Michael F. , Innis Sheila M. , Rodrigues Brian
Published: April 2006

Glucocorticoid therapy is often associated with impaired insulin sensitivity and cardiovascular disease. The present study was designed to evaluate cardiac fatty acid (FA) composition and metabolism following acute dexamethasone (Dex) treatment. Using the euglycemic hyperinsulinemic clamp, rats injected with Dex demonstrated a reduced glucose infusion rate. This whole body insulin resistance was also associated with a heart-specific increase in pyruvate dehydrogenase kinase 4 gene expression and a reduction in the rate of glucose oxidation. Dex treatment increased basal and postheparin plasma lipolytic activity. In the heart, palmitic and oleic acid levels were higher after 4 h of Dex and decreased to control (CON) levels within 8 h. Measurement of polyunsaturated FAs demonstrated a drop in linoleic and γ-linolenic acid, with an increase in arachidonic acid (AA) after acute Dex injection. Tissue FA can be either oxidized or stored as triglyceride (TG). At 4 h, Dex augmented cardiac TG accumulation. However, this increase in tissue TG could not be maintained, such that at 8 h following Dex, TG declined to CON levels. AMP-activated protein kinase (AMPK) activation is known to promote FA oxidation through its control of acetyl-CoA carboxylase (ACC). Acute Dex promoted ACC phosphorylation, and increased cardiac palmitate oxidation, likely through its effects in increasing AMPK phosphorylation and total AMPK protein and gene expression. Whether these acute effects of Dex on FA oxidation, TG storage, and arachidonic acid accumulation can be translated into increased cardiovascular risk following chronic therapy has yet to be determined.
GIP-(3–42) does not antagonize insulinotropic effects of GIP at physiological concentrations
Authors: Deacon Carolyn F. , Plamboeck Astrid , Rosenkilde Mette M. , de Heer Jocelyn , Holst Jens J.
Published: April 2006

Glucose-dependent insulinotropic polypeptide [GIP-(1–42)] is degraded by dipeptidyl peptidase IV (DPP IV), forming GIP-(3–42). In mice, high concentrations of synthetic GIP-(3–42) may function as a GIP receptor antagonist, but it is unclear whether this occurs at physiological concentrations. In COS-7 cells transiently transfected with the human GIP receptor, GIP-(1–42) and -(3–42) bind with affinities (IC50) of 5.2 and 22 nM, respectively. GIP-(1–42) was a potent agonist, stimulating cAMP accumulation (EC50, 13.5 pM); GIP-(3–42) alone had no effect. When incubated together with native GIP, GIP-(3–42) behaved as a weak antagonist (IC50, 92 and 731 nM for inhibition of cAMP accumulation elicited by 10 pM and 1 nM native GIP, respectively). In the isolated perfused rat pancreas, GIP-(3–42) alone had no effect on insulin output and only reduced the response to GIP (1 nM) when coinfused in >50-fold molar excess (IC50, 138 nM). The ability of GIP-(3–42) to affect the antihyperglycemic or insulinotropic actions of GIP-(1–42) was examined in chloralose-anesthetized pigs given intravenous glucose. Endogenous DPP IV activity was inhibited to reduce degradation of the infused GIP-(1–42), which was infused alone and together with GIP-(3–42), at rates sufficient to mimic postprandial concentrations of each peptide. Glucose, insulin, and glucagon responses were identical irrespective of whether GIP-(1–42) was infused alone or together with GIP-(3–42). We conclude that, although GIP-(3–42) can weakly antagonize cAMP accumulation and insulin output in vitro, it does not behave as a physiological antagonist in vivo.