bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance evaluation of mobile ad hoc routing protocols based on link expiration time and load of node
Authors: Hakoda Jun‐ichi , Uehara Hideyuki , Yokoyama Mitsuo 
Published: October 2003

AbstractIn mobile ad hoc networks, performance is degraded by link breakage due to node mobility and packet collision due to network congestion. Therefore, it is very attractive to investigate routing protocols which use a routing metric to discover long‐lived routes or to disperse network congestion instead of using hopwise shortest routes. In this paper, we examine three route selection schemes in a routing protocol which uses the link expiration time as a routing criterion. Furthermore, we present the Busy Node Avoidance Routing (BNAR) protocol that employs a busy rate representing the nodal load as a new route selection metric. Computer simulation results show the fundamental performance and effectiveness of routes based on the link state and node state. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(2): 68–78, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10137
MMSE adaptive array antenna with sequential processing
Authors: Ichikawa Yoshihiro , Tomitsuka Koji , Obote Shigeki , Kagoshima Kenichi 
Published: October 2003

AbstractAn important problem of the adaptive array antenna proposed previously in regard to its installation is the increased equipment size. This is because the adaptive array antenna requires as many RF circuits as the number of antenna elements. In this paper, in the case where there is an input in one system, we study an adaptive array antenna with sequential processing (AAA‐SP) in which the MMSE (minimum mean square error) criterion is used to control array weights by means of sequential processing of sampled signal data. Since there is only one input system in this case, it is found that the SINR is degraded due to reduction of correlation among elements if the conventional MMSE criterion is used as the adaptive control algorithm. Hence, in order to improve the deterioration of the SINR, a tapped‐delay‐line adaptive array antenna with sequential processing (TDL‐AAA‐SP) is proposed in which oversampling and a TDL‐AAA are combined. It is theoretically proven that the TDL‐AAA‐SP improves the SINR by recovering from reduction of correlation by means of correlation on the time axis. A computer simulation demonstrates that the proposed scheme is effective. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(2): 59–67, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10142
Measuring the sense of reality produced by highly realistic surround display systems: Application of an ARX model to observers' body‐sway data
Authors: Ohnishi Hitoshi , Mochizuki Kaname , Sugimoto Yuji Y. 
Published: October 2003

AbstractWe propose a quantitative method of evaluating observers' perceptions, that is, “feeling of immersion,” when a visual stimulus is displayed on a surround display. The proposed method uses the movement of an observer's center of gravity induced by a visual stimulus as an index. To analyze the quantitative relationship between body sway and visual stimuli, an ARX model was fitted to data obtained by measuring observers' body sway when a visual stimulus was displayed on surround displays. The results showed that adding horizontal screens increased the observers' body sway, whereas vertical screens did not when the visual stimulus moved in a rolling fashion. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(2): 46–58, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10150
Performance of an adaptive predistorted power amplifier with peak limited baseband code‐division multiplexed signal
Authors: Mizuta Shinji , Kawaguchi Hiroko , Akaiwa Yoshihiko 
Published: October 2003

AbstractIn FDM and CDM systems, the peak‐to‐average power ratio (PAPR) increases as the number of signals to be multiplexed is increased. When a signal with a large PAPR is incident on a power amplifier, either the out‐of‐band radiation is increased or the power efficiency is degraded. Methods of resolving these problems are nonlinear distortion compensation techniques, one of which is the predistorter. Another conceivable solution is to suppress the PAPR of the input signal. In this paper, we first study the performance when a limiter is used for the CDM signal in the baseband. By computer simulation, it is shown that the PAPR is suppressed by using a limiter and that the deterioration of the SIR performance is small if the PAPR is more than 6 dB. Next, the characteristics are studied by numerical simulation when a CDM signal with a limiter in the baseband is input to an adaptive predistorter‐type distortion‐compensated power amplifier. By combining the CDM signal with a limiter in the baseband and the adaptive predistorter‐type distortion‐compensated power amplifier, it is possible to suppress the out‐of‐band radiated power and simultaneously increase the power efficiency. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(2): 37–45, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10154
Characteristics of T‐type monopole antenna with parallel resonance mode
Authors: Sekine Syu‐ichi , Shoki Hiroki 
Published: October 2003

AbstractUse of dipole antennas for portable wireless transceivers has been attempted. In order to realize this application, it is necessary to add a matching network and a balun or a folded configuration. Hence, integration is found difficult. In this paper, a T‐type monopole antenna with a parallel resonance mode is proposed. It is shown by simulation and measurement with a 2‐GHz handset model that this antenna does not require any balun, is capable of self‐matching, and can suppress unwanted radiation from the case as for a dipole antenna. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(2): 28–36, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10157
Service specification description method for advanced intelligent network
Authors: Okamoto Mitsuhiro , Niitsu Yoshihiro 
Published: October 2003

AbstractThe communication service software (SLP) which realizes the communication service in advanced IN is usually generated automatically through a description of the service specification in a diagram format in the service generation environment (SCE). This paper considers such a description of the service specification in diagram format for SLP generation, and proposes a method of service specification description which allows easier description, is easier to understand, and has greater descriptive capability than the conventional description method. A widely used conventional description is the method proposed in ITU‐T, in which the descriptive elements (having the role of icons) correspond one‐to‐one to the service‐independent building blocks (SIBs). It sometimes happens, however, that the SIB as a functional unit is too large, degrading the reusability and understandability of the service specification. In contrast, the proposed description method is based on the information sequence diagram previously proposed by the authors, and extends the descriptive capability by adding descriptive elements so that the service specification of advanced IN can be described. The proposed description method was evaluated by nonexpert examinees, and it was verified that the description is easy and understandable. The proposed description method is also applied to SLP description of many commercial services, and it is verified that the necessary descriptive capability is provided. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(2): 17–27, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10162
Coaxial feed‐type microstrip patch antenna with variable antenna height
Authors: Kitatani Kazuhiro , Yamamoto Sadahiko 
Published: October 2003

AbstractThis paper describes a functional antenna with variable antenna height in which the coaxial feed section of the microstrip patch antenna is engineered. This is a new type of antenna combining mechatronic technology and the microstrip antenna so that the resonant frequency of the antenna can be varied by mechanical adjustment of the antenna height. In addition, since the patch can be rotated, the plane of polarization can also be rotated. This antenna has these two functionalities. In this paper, a simple theoretical investigation is carried out on the resonant frequency of the antenna. Further, the experimental results of the test antenna using a conventional dielectric substrate are presented. In the X band, the resonant frequency of the patch antenna can be varied by about 10% when the antenna height is changed by 0.3 mm. Larger variations of the resonant frequency are expected if high‐permittivity materials such as alumina are used as the substrate. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(2): 10–16, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10173
Permeable wave absorber
Authors: Nakamura Takashi , Ichikawa Takeshi , Sato Risaburo 
Published: October 2003

AbstractIn this paper, a new type of wave absorber permitting transmission is proposed. This absorber has a simple configuration consisting of a resistive film attached to the location where a metal backing is placed in an ordinary absorber. Allowance for transmitted waves and use of a lossless dielectric layer are the unique features. In contrast to the conventional wave absorber, a new degree of freedom is added to the structure and characteristics. By means of equivalent circuit analysis, the reflection and transmission coefficients of the present wave absorber are derived. The nonreflection condition is derived by taking into account the region behind the wave absorber. Based on this derivation, a wave absorber is designed and various characteristics are calculated. The validity of the theoretical results is confirmed by experiment. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(2): 1–9, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10174
Delay difference between tracking loops of different types or TL with various bandwidths of C/A code in GPS
Authors: Tachita Ryobun , Yasuda Akio 
Published: October 2003

AbstractIn GPS positioning by code timing, the accuracy of the basic stand‐alone positioning based only on information broadcast from GPS satellites is approximately 10 m (2 drms). But in GPS utilizing the results of observation by a reference station, the error due to the satellite and the channel can be eliminated, resulting in a positioning accuracy of 1 m (2 drms) or less. In applications in which high accuracy is required, although not as high as in carrier positioning, but in which the satellite signal is often interrupted, it is effective to use DGPS based on code timing. In DGPS based on code timing, the information acquired by a single reference station can be utilized by many rover stations. Different trackers are used in the reference and rover stations. This paper considers the DLL (delay lock loop) system, which is widely used in code tracking, and the SCELL (sampled code edge locked loop) system, with different characteristics. The differential error between the reference and rover stations which is caused by the difference in the receiver bandwidth, the satellite transmission bandwidth, and the difference in code numbers, is analyzed. It is shown that by widening the tracker bandwidth, the error is made sufficiently small compared to that obtained in ordinary DGPS. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(2): 91–98, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1186
Short proofs of classical theorems
Authors: Bondy J. A. 
Published: October 2003

AbstractWe give proofs of Ore's theorem on Hamilton circuits, Brooks' theorem on vertex coloring, and Vizing's theorem on edge coloring, as well as the Chvátal‐Lovász theorem on semi‐kernels, a theorem of Lu on spanning arborescences of tournaments, and a theorem of Gutin on diameters of orientations of graphs. These proofs, while not radically different from existing ones, are perhaps simpler and more natural. © 2003 Wiley Periodicals, Inc. J Graph Theory 44: 159–165, 2003
A list analogue of equitable coloring
Authors: Kostochka A. V. , Pelsmajer M. J. , West D. B. 
Published: October 2003

AbstractGiven lists of available colors assigned to the vertices of a graph G, a list coloring is a proper coloring of G such that the color on each vertex is chosen from its list. If the lists all have size k, then a list coloring is equitable if each color appears on at most $\lceil n (G)/k \rceil$ vertices. A graph is equitably k‐choosable if such a coloring exists whenever the lists all have size k. We prove that G is equitably k‐choosable when $k \ge {\rm max} \{ {\Delta (G),n(G)/2}\}$ unless G contains $K_{k+1}$ or k is odd and $G=K_{k,k}$. For forests, the threshold improves to $k \ge 1+\Delta (G)/2$. If G is a 2‐degenerate graph (given k ≥ 5) or a connected interval graph (other than $K_{k+1}$), then G is equitably k‐choosable when $k\ge \Delta(G)$. © 2003 Wiley Periodicals, Inc. J Graph Theory 44: 166–177, 2003
Critical groups for complete multipartite graphs and Cartesian products of complete graphs
Authors: Jacobson Brian , Niedermaier Andrew , Reiner Victor 
Published: October 2003

AbstractThe critical group of a connected graph is a finite abelian group, whose order is the number of spanning trees in the graph, and which is closely related to the graph Laplacian. Its group structure has been determined for relatively few classes of graphs, e.g., complete graphs and complete bipartite graphs. For complete multipartite graphs $K_{n_{1},\ldots, {n_k}}$, we describe the critical group structure completely. For Cartesian products of complete graphs $K_{n_{1}} \times \cdots \times K_{n_{k}}$, we generalize results of H. Bai on the k‐dimensional cube, by bounding the number of invariant factors in the critical group, and describing completely its p‐primary structure for all primes p that divide none of $n_1, \ldots, n_k$. © 2003 Wiley Periodicals, Inc. J Graph Theory 44: 231–250, 2003
Steiner type problems for digraphs that are locally semicomplete or extended semicomplete
Authors: Bang‐Jensen Jørgen , Gutin Gregory , Yeo Anders 
Published: October 2003

AbstractWe consider the following three problems: (P1) LetDbe a strong digraph and letXbe a non‐empty subset of its vertices. Find a strong subdigraphD′ ofDwhich contains all vertices ofXand has as few arcs as possible. This problem is also known under the name the directed Steiner problem. (P2) LetDbe a strong digraph with real‐valued costs on the vertices. Find a strong subdigraph ofDof minimum cost. (P3) LetDbe a strong digraph with real‐valued costs on the vertices. Find a cycle of minimum cost inD. All three problems are NP‐hard for general digraphs. The second problem generalizes the problem of finding a smallest strong subdigraph (measured in the number of vertices) which covers a given non‐empty setXof vertices. We describe polynomial algorithms for the problems (P1) and (P2) in the case whenDis either locally semicomplete or extended semicomplete and for (P3) in the case of locally semicomplete digraphs. A polynomial algorithm for (P3) in the case of extended semicomplete digraphs was given by Bang‐Jensen et al.,2002. © 2003 Wiley Periodicals, Inc. J Graph Theory 44: 193–207, 2003
Hamilton decompositions of complete multipartite graphs with any 2‐factor leave
Authors: Leach C. D. , Rodger C. A. 
Published: October 2003

AbstractFor m ≥ 1 and p ≥ 2, given a set of integers s1,…,sq with $s_j \geq p+1$ for $1 \leq j \leq q$ and ${\sum _{j\,=\,1}^q} s_j = mp$, necessary and sufficient conditions are found for the existence of a hamilton decomposition of the complete p‐partite graph $K_{m,\ldots,m} - E(U)$, where U is a 2‐factor of $K_{m,\ldots,m}$ consisting of q cycles, the jth cycle having length sj. This result is then used to completely solve the problem when p = 3, removing the condition that $s_j\ge p+1$. © 2003 Wiley Periodicals, Inc. J Graph Theory 44: 208–214, 2003
On a conjecture of Brualdi and Shen on block transitive tournaments
Authors: Acosta P. , Bassa A. , Chaikin A. , Riehl A. , Tingstad A. , Zhao L. , Kleitman D. J. 
Published: October 2003

AbstractThe following conjecture of Brualdi and Shen is proven in this paper: let n be partitioned into natural numbers no one of which is greater than (n + 1) / 2. Then, given any sequence of wins for the players of some tournament among n players, there is a partition of the players into blocks with cardinalities given by those numbers, and a tournament with the given sequence of wins, that is transitive on the players within each block. © 2003 Wiley Periodicals, Inc. J Graph Theory 44: 215–230, 2003
Self‐clique graphs and matrix permutations
Authors: Bondy Adrian , Durán Guillermo , Lin Min Chih , Szwarcfiter Jayme L. 
Published: October 2003

AbstractThe clique graph of a graph is the intersection graph of its (maximal) cliques. A graph is self‐clique when it is isomorphic with its clique graph, and is clique‐Helly when its cliques satisfy the Helly property. We prove that a graph is clique‐Helly and self‐clique if and only if it admits a quasi‐symmetric clique matrix, that is, a clique matrix whose families of row and column vectors are identical. We also give a characterization of such graphs in terms of vertex‐clique duality. We describe new classes of self‐clique and 2‐self‐clique graphs. Further, we consider some problems on permuted matrices (matrices obtained by permuting the rows and/or columns of a given matrix). We prove that deciding whether a (0,1)‐matrix admits a symmetric (quasi‐symmetric) permuted matrix is graph (hypergraph) isomorphism complete. © 2003 Wiley Periodicals, Inc. J Graph Theory 44: 178–192, 2003
If only I hadn't smoked: The impact of counterfactual thinking on a smoking‐related behavior
Authors: Page Christine M. , Colby Patricia M. 
Published: October 2003

AbstractThe role of counterfactual thinking as an effective antismoking communications strategy is examined. Specifically, this study investigates how various types of counterfactual thoughts, generated in response to a detrimental smoking scenario, impact individuals' affective evaluations of the scenario, as well as their willingness to participate in a smoking‐related behavioral test, a lung‐capacity test. This is tested in three experiments, which differ in the timing of gathering individuals' willingness to participate in the lung‐capacity test. Experiment 1 collected individuals' willingness to participate in the test shortly after the counterfactual task, whereas Experiments 2 and 3 made this assessment 2 and 7 days following the counterfactual task (respectively). The results of all three experiments indicated that although upward counterfactuals had a negative impact on individuals' affective evaluations of the scenario, they had no effect on participants' willingness to schedule a lung‐ capacity test. Alternatively, additive counterfactuals did have a significant impact on individuals' preparative actions, despite having no influence on their affective evaluations. This effect, however, decreased with time. By demonstrating that counterfactual thinking may significantly influence smoking‐related behaviors, this study's findings contribute to and extend prior counterfactual and antismoking research. © 2003 Wiley Periodicals, Inc.
The relationship between product involvement and product knowledge: Moderating roles of product type and product knowledge type
Authors: Park Chan‐Wook , Moon Byeong‐Joon 
Published: October 2003

AbstractTo shed further light on the correlation between consumer product involvement and consumer product knowledge, the authors examined such correlation by treating product type and product knowledge type as moderating variables. The results show that the correlation between a consumer's product involvement and objective product knowledge is higher in a utilitarian product than in a hedonic product. On the contrary, the correlation between a consumer's product involvement and subjective product knowledge is higher in a hedonic product than in a utilitarian product. The implications of these results are discussed. © 2003 Wiley Periodicals, Inc.
Dueling or the battle royale? The impact of task complexity on the evaluation of entry threat
Authors: Klemz Bruce R. , Gruca Thomas S. 
Published: October 2003

AbstractCurrent marketing research on response to entry assumes that an incumbent decision maker faces potential rivals one at a time as in a series of duels. In many circumstances, however, an incumbent decision maker faces a large number of entrants simultaneously (a “battle royale”). An experiment using experienced managers shows that the increased complexity produced by multiple entrants had a significant effect on the managers' decision processes and their decision outcomes. Specifically, when faced with multiple entrants, the managers adopted more noncompensatory decision processes, and were more likely to misidentify the most threatening entrant as defined by their self‐explicated weights or conjoint part‐worths. These results provide insight into an unexplained gap between the extant normative and empirical research on response to entry. © 2003 Wiley Periodicals, Inc.
“I know this brand, but did I like the ad?” An investigation of the familiarity‐based sleeper effect
Authors: Pashupati Kartik 
Published: October 2003

AbstractAn experiment was designed to investigate the existence of the familiarity‐based sleeper effect proposed by Moore and Hutchinson (1983, 1985). The study also investigated the effects of advertisement repetition on the relationship between attitude toward the ad (Aad) and attitude toward the brand (Ab). Television commercials, embedded in a 30‐min television program, were used as stimuli. A between‐subjects factorial design was used, with 12 cells: three ad types (positive, neutral, and negative), two repetition levels (one versus three exposures to the test commercial) and two delay conditions (Ab was measured either immediately after exposure or 7 days later). The data do not support the existence of a sleeper effect, and provide limited support for the other hypotheses proposed in the study. © 2003 Wiley Periodicals, Inc.
The effect of supply chain glitches on shareholder wealth
Authors: Hendricks Kevin B. , Singhal Vinod R. 
Published: October 2003

AbstractThis paper estimates the shareholder wealth affects of supply chain glitches that resulted in production or shipment delays. The results are based on a sample of 519 glitches announcements made during 1989–2000. Shareholder wealth affects are estimated by computing the abnormal stock returns (actual returns adjusted for industry and market‐wide influences) around the date when information about glitches is publicly announced. Supply chain glitch announcements are associated with an abnormal decrease in shareholder value of 10.28%. Regression analysis is used to identify factors that influence the direction and magnitude of the change in the stock market’s reaction to glitches. We find that larger firms experience a less negative market reaction, and firms with higher growth prospects experience a more negative reaction. There is no difference between the stock market’s reaction to pre‐1995 and post‐1995 glitches, suggesting that the market has always viewed glitches unfavorably. Capital structure (debt–equity ratio) has little impact on the stock market’s reaction to glitches. We also provide descriptive results on how sources of responsibility and reasons for glitches affect shareholder wealth.