bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance analysis under dynamic loading of wavelength continuous and non‐continuous WDM networks with shortest‐path routing
Authors: Shen Gangxiang , Bose Sanjay K. , Cheng Tee Hiang , Lu Chao , Chai Teck Yoong
Published: August 2002

The performance of WDM networks using shortest path routing is studied under wavelength continuous (WC) and non‐continuous (NWC) constraints and dynamic traffic loading. Approximate analytical models are presented for the performance studies of such systems. Results of numerical calculations based on these models and simulations are given for different network topologies for the purposes of comparison. These analytical and simulation results are used to study the performance of these WDM networks under dynamic traffic loading. Copyright © 2001 John Wiley & Sons, Ltd.
Active versus latent representations: A neural network model of perseveration, dissociation, and decalage
Authors: Morton J. Bruce , Munakata Yuko
Published: August 2002

Children of different ages often perseverate, repeating previous behaviors when they are no longer appropriate, despite appearing to know what they should be doing. Using neural network models, we explore an account of these phenomena based on a distinction between active memory (subserved by the prefrontal cortex) and latent memory (subserved by posterior cortex). The models demonstrate how (a) perseveration occurs when an active memory of currently relevant knowledge is insufficiently strong to overcome a latent bias established by previous experience, (b) apparent dissociations between children's knowledge and action may reflect differences in the amount of conflict between active and latent memories that children need to resolve in the tasks, and (c) differences in when children master formally similar tasks (decalage) may result from differences in the strength of children's initial biases. The models help to clarify how prefrontal development may lead to advances in flexible thinking. © 2002 Wiley Periodicals, Inc. Dev Psychobiol 40: 255–265, 2002. DOI 10.1002/dev.10033
Intentional social action in virtual communities
Authors: Bagozzi Richard P. , Dholakia Utpal M.
Published: August 2002

There is growing evidence of the increasing participation in, and influence of, virtual communities in digital environments. To help explain this irresistible allure, the individual and social determinants of the member's intentions to participate are investigated. Conceptualizing virtual community participation as intentional social action, we explicate the concept of “we-intentions”, and use the Model of Goal-Directed Behavior to explain members’ we-intentions. Virtual community influences pertaining to compliance, internalization, and social identity are also elaborated on. An empirical study of regular virtual community participants ( N = 157) finds that we-intentions to participate are functions of both individual determinants (positive anticipated emotions and desires), and community influences (social identity). Implications for marketing and future research opportunities are discussed.
Heparan sulfate proteoglycans in experimental models of diabetes: a role for perlecan in diabetes complications
Authors: Conde‐Knape Karin
Published: August 2002

Proteoglycans are ubiquitous extracellular proteins that serve a variety of functions throughout the organism. Unlike other glycoproteins, proteoglycans are classified based on the structure of the glycosaminoglycan carbohydrate chains, not the core proteins. Perlecan, a member of the heparan sulfate proteoglycan (HSPG) family, has been implicated in many complications of diabetes. Decreased levels of perlecan have been observed in the kidney and in other organs, both in patients with diabetes and in animal models. Perlecan has an important role in the maintenance of the glomerular filtration barrier. Decreased perlecan in the glomerular basement membrane has a central role in the development of diabetic albuminuria. The involvement of this proteoglycan in diabetic complications and the possible mechanisms underlying such a role have been addressed using a variety of models. Due to the importance of nephropathy among diabetic patients most of the studies conducted so far relate to diabetes effects on perlecan in different types of kidney cells. The various diabetic models used have provided information on some of the mechanisms underlying perlecan's role in diabetes as well as on possible factors affecting its regulation. However, many other aspects of perlecan metabolism still await full elucidation.

The present review provides a description of the models that have been used to study HSPG and in particular perlecan metabolism in diabetes and some of the factors that have been found to be important in the regulation of perlecan. Copyright © 2001 John Wiley & Sons, Ltd.
Region‐ and stage‐specific effects of FGFs and BMPs in chick mandibular morphogenesis
Authors: Mina Mina , Wang Yu‐Hsing , Ivanisevic Ana‐Maria , Upholt William B. , Rodgers Barbara
Published: August 2002

The mandibular processes are specified as at least two independent functional regions: two large lateral regions where morphogenesis is dependent on fibroblast growth factor (FGF)‐8 signaling, and a small medial region where morphogenesis is independent of FGF‐8 signaling. To gain insight into signaling pathways that may be involved in morphogenesis of the medial region, we have examined the roles of pathways regulated by FGFs and bone morphogenetic proteins (BMPs) in morphogenesis of the medial and lateral regions of the developing chick mandible. Our results show that, unlike in the lateral region, the proliferation and growth of the mesenchyme in the medial region is dependent on signals derived from the overlying epithelium. We also show that medial and lateral mandibular mesenchyme respond differently to exogenous FGFs and BMPs. FGF‐2 and FGF‐4 can mimic many of the effects of mandibular epithelium from the medial region, including supporting the expression of Msx genes, outgrowth of the mandibular processes and elongation of Meckel's cartilage. On the other hand, laterally placed FGF beads did not induce ectopic expression of Msx genes and did not affect the growth of the mandibular processes. These functional studies, together with our tissue distribution studies, suggest that FGF‐mediated signaling (other than FGF‐8), through interactions with FGF receptor‐2 and downstream target genes including Msx genes, is part of the signaling pathway that mediates the growth‐promoting interactions in the medial region of the developing mandible. Our observations also suggest that BMPs play multiple stage‐ and region‐specific roles in mandibular morphogenesis. In this study, we show that exogenous BMP‐7 applied to the lateral region at early stages of development (stage 20) caused apoptosis, ectopic expression of Msx genes, and inhibited outgrowth of the mandibular processes and the formation of Meckel's cartilage. Our additional experiments suggest that the differences between the effects of BMP‐7 on lateral mandibular mesenchyme at stage 20 and previously reported results at stage 23 (Wang et al., [1999] Dev. Dyn. 216:320–335) are related to differences in stages of differentiation in that BMP‐7 promotes apoptosis in undifferentiated lateral mandibular mesenchyme, whereas it promotes chondrogenesis at later stages of development. We also showed that, unlike mandibular epithelium and medially placed FGF beads, medially placed BMP‐7 did not support outgrowth of the isolated mesenchyme and at stage 20 induced the formation of a duplicated rod of cartilage extending from the body of Meckel's cartilage. These observations suggest that BMPs do not play essential roles in growth‐promoting interactions in the medial region of the developing mandible. However, BMP‐mediated signaling is a part of the signaling pathways regulating chondrogenesis of the mandibular mesenchyme. © 2002 Wiley‐Liss, Inc.
Matrix metalloproteinases mediate the dismantling of mesenchymal structures in the tadpole tail during thyroid hormone‐induced tail resorption
Authors: Jung Jae‐Chang , Leco Kevin J. , Edwards Dylan R. , Fini M. Elizabeth
Published: August 2002

It has been suggested that a family of tissue remodelling enzymes called matrix metalloproteinases (MMPs) play a causal role in the process of tail resorption during thyroid hormone‐induced metamorphosis of the anuran tadpole; however, this hypothesis has never been directly substantiated. We cloned two new Xenopus MMPs, gelatinase A (MMP‐2) and MT3‐MMP (MMP‐16), and the MMP inhibitor TIMP‐2. These clones were used along with several others to perform a comprehensive expression study. We show that all MMPs and TIMP‐2 are dramatically induced in the resorbing tail during spontaneous metamorphosis and are spatially coexpressed, primarily in the remodelling mesenchymal tissues. By Northern blotting, we show that all the examined MMPs/TIMP‐2 are also induced by treatment of organ‐cultured tails with thyroid hormone (T3). Using the organ culture model, we provide the first direct evidence that MMPs are required for T3‐induced tail resorption by showing that a synthetic inhibitor of MMP activity/expression can specifically retard the resorption process. By gelatin zymography, we also show T3 induction of a fifth MMP, preliminarily identified as gelatinase B (GelB; MMP‐9). Moreover, T3 not only induces MMP/TIMP expression but also MMP activation, and we provide evidence that TIMP‐2 participates in the latter process. These findings suggest that MMPs and TIMPs act in concert to effect the dismantling of mesenchymal structures during T3‐induced metamorphic tadpole tail resorption. © 2002 Wiley‐Liss, Inc.
Mouse PeP: A novel peroxisomal protein linked to myoblast differentiation and development
Authors: Ferrer‐Martínez Andreu , Ruiz‐Lozano Pilar , Chien Kenneth R.
Published: August 2002

The identification of several peroxisomal proteins in the past decade has deepened our understanding of the biology of peroxisomes and their involvement in human disorders. We report the cloning and expression pattern during the mouse development of a cDNA encoding a novel protein, named PeP, and show that its product is imported specifically to the peroxisome matrix in a variety of cell types. We also demonstrate that PeP is imported to the organelle through the PEX5 receptor pathway, which indicates that the C‐terminal tripeptide SKI behaves as a type 1 peroxisomal targeting signal (PTS1). PeP expression is tightly regulated, as shown by Northern and in situ hybridization experiments. Thus during embryonic development in the mouse, PeP mRNA is detected almost exclusively in the skeletal muscle, whereas in adult mice, strong expression is also found in the heart and brain. In addition, PeP mRNA accumulation is induced after myoblast differentiation in vitro, when myotube formation is promoted. Sequence analysis reveals that PeP has no significant homology to any known protein, except for a short stretch of amino acids containing the fingerprint of the fibronectin type III superfamily, a domain present in proteins often related to molecular and cellular recognition and binding processes. Thus our data suggest a connection between the function of PeP and murine cell differentiation and development. © 2002 Wiley‐Liss, Inc.
Disruption of erythropoiesis by dioxin in the zebrafish
Authors: Belair Cassandra D. , Peterson Richard E. , Heideman Warren
Published: August 2002

2,3,7,8‐Tetrachlorodibenzo‐p‐ dioxin (TCDD, or dioxin) causes early life stage mortality in a variety of fish species. We have used the zebrafish (Danio rerio) to study the cardiovascular effects of TCDD treatment over the time course of zebrafish development. Early TCDD exposure (6 ng/ml) starting at 4 hr postfertilization (hpf) produced reductions in blood flow and in the number of circulating erythrocytes. These defects were consistently observable by 72 hpf. However, these responses were not observed when TCDD exposure was delayed until 96 hpf or later. These results suggest a model in which TCDD interferes with cardiovascular and erythropoietic developmental processes that are normally completed by 96 hpf. This model is strengthened by the finding that TCDD exposure blocks the step in hematopoiesis in which developing zebrafish switch from the primitive phase to the definitive phase of erythropoiesis. We observed no effect of TCDD on the levels of circulating primitive erythrocytes before 72 hpf and the expression of markers for early hematopoiesis, GATA‐1 and GATA‐2. However, early TCDD exposure prevented the appearance of definitive phase erythrocytes. TCDD produced a small delay in the migration of blood cells expressing SCL from the intermediate cell mass to the dorsal mesentery and dorsal aorta. Despite the decrease in blood flow produced by TCDD, confocal microscopy of the trunk vasculature by using a Tie2/green fluorescence protein endothelial marker at 48, 60, 72, and 96 hpf of TCDD‐exposed (4 hpf) revealed no apparent defects in blood vessel structure. © 2001 Wiley‐Liss, Inc.
Evidence for implicit sequence learning in dyslexia
Authors: Kelly Steve W. , Griffiths Sarah , Frith Uta
Published: August 2002

Nicolson and Fawcett (Cognition 1990; 35: 159–182) have suggested that a deficit in the automatization of skill learning could account for the general impairments found in dyslexia. Much of the evidence for their claims has been collected via a dual task paradigm, which might allow for alternative explanations of the data. The present study examines automatic skill learning in a single task paradigm and extends previous studies by independently examining the contribution of stimulus‐based and response‐based learning. The task replicates Mayr's (J. Exp. Psychol.: Learning Memory Cognition 1996; 22: 350–364) methodology in the Serial Reaction Time task by exposing participants to two structured displays, simultaneously. Learning is measured by comparing RT to the learned sequence against RT to a random display. This study demonstrates learning for both dyslexic and control groups for a spatial sequence which was observed and a concurrent non‐spatial sequence which was responded to via a keypress. Learning of the sequence did not seem to depend on awareness of the sequence structure. These results suggest that automatic skill learning is intact in dyslexic individuals. Copyright © 2002 John Wiley & Sons, Ltd.
The media's representation of the ideal male body: A cause for muscle dysmorphia?
Authors: Leit Richard A. , Gray James J. , Pope Harrison G.
Published: August 2002

Objective

This study sought to examine the effects of media images on men's attitudes toward their body appearance.

Method

A group of college men viewed advertisements showing muscular men, whereas a control group viewed neutral advertisements. Immediately thereafter, participants performed a computerized test of body image perception while unaware of the hypotheses being tested in the study.

Results

The students exposed to the muscular images showed a significantly greater discrepancy between their own perceived muscularity and the level of muscularity that they ideally wanted to have.

Discussion

These findings suggest that media images, even in a brief presentation, can affect men's views of their bodies. © 2002 by Wiley Periodicals, Inc. Int J Eat Disord 31: 334–338, 2002; DOI 10.1002/eat.10019
The impact of body image experiences: Development of the body image quality of life inventory
Authors: Cash Thomas F. , Fleming Emily C.
Published: August 2002

Objective

Substantial research confirms that body image affects multiple aspects of psychosocial functioning, yet there is no direct assessment to quantify its impact on an individual's quality of life.

Method

In the present study, the Body Image Quality of Life Inventory was developed and empirically evaluated with 116 college women.

Results and Discussion

This 19‐item assessment was internally consistent and stable over a 2‐ to 3week period. It converged significantly with multiple measures of body image evaluation and investment and with body mass. The results further revealed that women in the sample reported more positive than negative consequences of their body image for various domains of life. The implications of these findings and directions for continued validation of this unique measure are considered. © 2002 by Wiley Periodicals, Inc. Int J Eat Disord 31: 455–460, 2002
Homosexuality as a specific risk factor for eating disorders in men
Authors: Russell Christopher J. , Keel Pamela K.
Published: August 2002

Objective

The current study examined whether homosexuality is a specific risk factor for disordered eating in men.

Method

Men (64 heterosexual and 58 homosexual) completed the Beck Depression Inventory (BDI), the Rosenberg Self‐Esteem Scale (RSE), the Masculinity and Femininity scales of the Bem Sex‐Role Inventory (BSRI), the Bulimia Test‐Revised (BULIT‐R), the Eating Attitudes Test (EAT‐26), and the Body Shape Questionnaire (BSQ).

Results

Homosexual men had more pathological scores on the BDI, RSE, BULIT‐R, EAT‐26, and BSQ. Additionally, homosexual men reported greater discomfort with sexual orientation. After controlling for differences in depression, self‐esteem, and comfort with sexual orientation, sexual orientation continued to account for significant variance in BULIT‐R, EAT‐26, and BSQ scores.

Discussion

Future research may benefit from exploring aspects of homosexuality that may contribute specifically to risk for disordered eating in men. © 2002 by Wiley Periodicals, Inc. Int J Eat Disord 31: 300–306, 2002; DOI 10.1002/eat.10036
A randomized trial of a dissonance‐based eating disorder prevention program
Authors: Stice Eric , Chase Allison , Stormer Susan , Appel Anne
Published: August 2002

Objective

As psychoeducational eating disorder prevention programs have not been shown to reduce bulimic pathology, we developed and evaluated a dissonance‐based intervention for high‐risk populations.

Method

Young women (N = 87) with body image concerns were randomized to this intervention, which involves verbal, written, and behavioral exercises requiring them to critique the thin‐ideal, or to a healthy weight management control group. Participants completed a baseline, termination, and 4‐week follow‐up survey.

Results

Participants in the dissonance intervention reported decreased thin‐ideal internalization, body dissatisfaction, dieting, negative affect, and bulimic symptoms at termination and at 4‐week follow‐up. Unexpectedly, participants in the healthy weight management control group also reported some benefits.

Discussion

Taken in conjunction with past findings, these preliminary results suggest that the dissonance intervention, and to a lesser extent the healthy weight management intervention, may reduce bulimic pathology and risk factors for eating disturbances. © 2001 by John Wiley & Sons, Inc. Int J Eat Disord 29: 247–262, 2001.
Sexual orientation and eating psychopathology: The role of masculinity and femininity
Authors: Meyer Caroline , Blissett Jackie , Oldfield Claire
Published: August 2002

Objective

Previous research suggests that eating disorders are related to homosexuality in men, although links with female sexual orientation are less clear. Appearance factors have generally been implicated in this relationship. However, previous studies have failed to consider the role of femininity, even though evidence suggests that this is a more critical factor than sexual preference. The aim of this study was to consider the relationship between gender‐role orientation and eating psychopathology in nonclinical men and women of different sexual orientations.

Method

One hundred university students (40 homosexual; 60 heterosexual) completed the Bem Sex Role Inventory and the Eating Attitudes Test.

Results

For the group as a whole, there were links between femininity and high levels of eating psychopathology, whereas masculinity was associated with relatively healthy eating‐related attitudes and behaviors. When considering the role of sexual orientation, these links were specific to homosexual men and women.

Conclusions

In relation to homosexual men and women, the results support a model where femininity might be seen as a specific risk factor for eating disorders, whereas masculinity is likely to be a protective factor. Methodological and conceptual implications are discussed. © 2001 by John Wiley & Sons, Inc. Int J Eat Disord 29: 314–318, 2001.
Body image in boys: A review of the literature
Authors: Cohane Geoffrey H. , Pope Harrison G.
Published: August 2002

Objective

Both scientific research and popular attention have begun to focus on the neglected issue of body image in boys. We reviewed the findings of this emerging literature.

Method

Using computer and manual search techniques, we located 17 studies that assessed body image attitudes in boys under age 18.

Results

We located 17 studies, most performed within the last 10 years. Eight studies used exclusively questionnaires or interviews; the rest also used figure drawings from which the subjects could choose specific images in answer to questions. Although boys generally displayed less overall body concern than girls, many boys of all ages reported dissatisfaction with their bodies, often associated with reduced self‐esteem. Whereas girls typically wanted to be thinner, boys frequently wanted to be bigger. However, most studies failed to distinguish between “bigness” due to increased muscle and that due to fat.

Conclusions

Body image dissatisfaction in boys is common and often associated with distress. To better assess this phenomenon, future studies should take care to separate the indices of muscle and fat. © 2001 by John Wiley & Sons, Inc. Int J Eat Disord 29: 373–379, 2001.
A crossbar ATM switch for multicast traffic
Authors: Sakuta Makoto , Hiyama Satoshi , Nishino Yoshiyuki , Sasase Iwao
Published: August 2002

A crossbar ATM switch for multicast traffic is proposed. First, we propose a crossbar ATM switch to which is added a new state of a switch element capable of performing cell replication at the routing crossbar, with a header translator placed in front of the concentrator following the routing crossbar, as the proposed model 1. By adding minimal faculties to the conventional model, proposed model 1 can cope with multicast traffic without degrading the performance of the conventional model. However, due to treatment of multicast traffic in proposed model 1, output congestion is liable to occur. Furthermore, cells which do not complete cell replication and cell routing at the routing crossbar are sent to the concentrator. That is, the ratio of cells lost by concentration at the concentrator increases and the cell loss probability is degraded. Second, we propose a crossbar ATM switch where the concentrator is removed and all the output lines of the header translator are connected to a shared buffer, as the proposed model 2. We use computer simulations to compare the performance of proposed model 2 with that of proposed model 1 for mixed traffic with unicast and multicast cells with respect to cell loss probability and mean delay. It is shown that proposed model 2 can improve cell loss probability performance dramatically for low and medium loads. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 84(11): 16–25, 2001
Study of cluster feed system with hybrid low‐level beam‐forming network
Authors: Tokunaga Kyoko , Tsunoda Hiroaki , Yamasa Yasuhiko , Orikasa Teruaki
Published: August 2002

Cluster feeds have been widely adopted as multibeam antenna feeds for communications satellites because they can realize high edge levels. A low‐level feed system in which amplifiers are connected after beam‐forming networks is especially effective in reducing the feed loss. The beam‐forming network is not required to withstand high powers. This system is promising as a feed system of a multibeam antenna that needs to transmit high power. However, it is difficult to equalize the operational level of amplifiers in a low‐level feed system. This paper proposes a hybrid low‐level feed system that can equalize the operational levels of amplifiers in order to use the amplifiers more efficiently. Analysis shows properties of a design of an antenna that adopted this system. Antenna elements and beam‐forming networks were produced. The primary patterns were measured, and the secondary patterns were calculated using these results. A comparison of the design with the calculation results shows that a multibeam antenna with high gain and low side lobes is realizable with this system. The components into which high power is input, are proved capable of withstanding high power and verified the generated level of PIM. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 84(11): 35–43, 2001
Identification of propagation path from low antenna height base station in urban area
Authors: Furuno Tatsuo , Taga Tokio
Published: August 2002

The delay spread characteristics in low antenna height propagation in urban areas are difficult to accurately estimate by statistical methods that are highly dependent on the location. To understand how the road system affects the propagation characteristics, the propagation mechanism was analyzed. In practice, the identification of the propagation paths has been attempted by measuring the direction of arrived waves and the delay propagation time (propagation path length) at line‐of‐sight and non‐line‐of‐sight locations. The results clearly showed that many arrived waves are propagated by geometric optical reflections by the walls of buildings, diffractions at the corners of intersections, and their combinations. Furthermore, the calculated results and measurements were compared based on geometric optical methods and wedge diffraction theory to demonstrate the usefulness of geometric optical computational methods. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 84(12): 41–51, 2001
Performance analysis of indoor infrared wireless systems using PPM CDMA
Authors: Ohtsuki Tomoaki
Published: August 2002

Indoor infrared wireless systems using pulse position modulation (PPM) code division multiple access (CDMA) have attracted much attention, because PPM CDMA can realize random access with the same wavelength. In addition, PPM CDMA has high power efficiency. The system referred to as PPM CDMA in the field of infrared wireless communications is usually referred to as CDMA with multibits/sequence in the field of optical fiber networks. The interference probability used in the literature on infrared wireless PPM CDMA systems is not applicable, and thus the correct performance of such systems has not been clarified. In this paper, we analyze the correct performance of indoor infrared wireless PPM CDMA systems. We assume a system using APD and use Gaussian approximation for the APD output. We analyze the performance in the chip synchronous case with consideration of APD noise, thermal noise, background noise, and interference noise. We show that indoor infrared wireless PPM CDMA can realize multiple access while reducing the required transmit power, compared with systems using on‐off keying (OOK) CDMA. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 85(1): 1–10, 2002
A proposal of a vehicle network using intervehicle transmission method
Authors: Yashiro Tomoyuki , Matsushita Yutaka
Published: August 2002

In this paper, a mobile vehicle network is proposed to be utilized for intervehicle communication. A network building method is described based on using spread spectrum communication technique and establishing individual links between each vehicle while combining communication and distance measurement between the vehicles within a defined area. In order to more completely utilize network capability, a new concept of zone is introduced and defined. Along with the explanation of the network building method, the evaluation of practical usage of such networks based on computer simulation techniques is also provided. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 85(3): 40–50, 2002
A method of SAR measurement using a high‐molecular‐weight gel phantom: On the correspondence of the surface of the clouded region to the surface of equipower absorption
Authors: Hoshina Shinichiro , Miyakawa Michio , Kanai Yasushi , Kashiwa Tatsuya
Published: August 2002

As a method for evaluating the electromagnetic exposure of biological bodies, a visualization technique of the absorbed power inside the phantom using high‐molecular‐weight gel is proposed. Such gel containing a small amount of nonionic surfactants has the property of quickly becoming clouded at a temperature above a certain value. Therefore, it is possible to observe the portion with a temperature increase due to absorption of electromagnetic energy as a clouded region. The surface of the clouded region represents an equitemperature surface indicating the temperature at which the phantom is clouded. Hence, this is basically the equal power absorption surface. However, depending on the influence of the thermal conduction, the shape of the clouded region and the absorption power distribution may not coincide. In this paper, the equality of the clouded region shape and the equal power absorption surface is verified. The measured shape of the clouded region formed inside the phantom and the absorbed power distribution within the phantom derived by the three‐dimensional FD‐TD (Finite‐Difference Time‐Domain) method are compared. In addition, the influence of thermal conduction on the temperature distribution in the phantom is discussed. It is confirmed that the clouded shape caused by electromagnetic wave exposure and the computed equal power absorption surface agree well if the electromagnetic wave illumination time is less than about 1 minute. The validity of this method measuring the amount of electromagnetic wave exposure from the clouded shape is confirmed. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 85(3): 51–60, 2002
Study of statistical model and power measurement results for distortions due to clipping in SCM optical transmission system
Authors: Maeda Kazuki , Tsukamoto Katsutoshi , Komaki Shouzo
Published: August 2002

In the SCM optical transmissions used in optical CATV, it has been pointed out that the distortion generated by clipping behaves in the same way as impulse noise. In this paper, it is assumed that the distortion due to clipping is generated following the Poisson distribution, with the same characteristics as the band‐limited noise, and it is demonstrated theoretically that the amplitude distribution follows Middleton's class A model. On the other hand, there have been many discussions of the theoretical value of the distortion power due to clipping. This study notes that the measurement of the noise power by the spectrum analyzer essentially contains a measurement error. Using the statistical model for the distortion amplitude derived in this paper, the measurement error is calculated for the case in which the amplitude distribution of the distortion due to clipping follows that of the impulse noise. The calculation result is compared to the measurement results and the amount of correction is theoretically derived for the very large error present in the distortion value indicated by the spectrum analyzer. In the SCM optical transmission used in optical CATV, the measured distortion is smaller than the actual value at the ordinary employed optical modulation index. The difference may sometimes reach 20 dB. When the measured value is corrected for the error by the method presented in this paper, the theoretical value of the distortion by clipping, as obtained from Saleh's expression, is almost entirely adequate. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 85(8): 13–22, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1114
A 2‐V, 1‐MHz, 7‐bit, third‐order noise shaping A‐D converter
Authors: Terada Jun , Matsuya Yasuyuki
Published: August 2002

With the aim of stabilizing high‐order noise‐shaping circuits, a third‐order swing‐suppression A‐D converter featuring low‐voltage operation and megahertz‐band conversion has been developed. This converter achieves a high S/N ratio without having to insert attenuation coefficients as in conventional integrators. In this design, output from quantizers is fed back to a third integrator input to stabilize the loop, and degradation of the S/N ratio due to stabilizing coefficients is suppressed since their insertion is not needed. This A‐D converter operates at a power‐supply voltage of 2 V, achieves accuracy of 7 and 6 bits at input signal bands of 1 and 2 MHz, respectively, and consumes 45 mW of power. © 2001 Scripta Technica, Electron Comm Jpn Pt 2, 84(4): 1–8, 2001
Initial anomalous diffusion of boron atoms at low‐temperature annealing
Authors: Saito Tomoya , Xia Jianxin , Kim Ryangsu , Aoki Takenori , Kobayashi Hiroyuki , Furuta Yoshikazu , Kamakura Yoshinari , Taniguchi Kenji
Published: August 2002

Experiments on the transient enhanced diffusion (TED) of boron in superlattice silicon wafers, for the first time demonstrated the existence of the anomalous enhanced diffusion of boron at the very early stage of low‐temperature annealing at locations situated deeper than the implantation damage zone. It was confirmed that this phenomenon is caused by free self‐interstitial silicon atoms present in the implantation tail region. © 2001 Scripta Technica, Electron Comm Jpn Pt 2, 84(10): 59–64, 2001
DANSE: Dynamically adaptive networking service environment
Authors: Itao Tomoko , Matsuo Masato
Published: August 2002

The DANSE (Dynamically Adaptive Networking Service Environment), which constructs an environment (service environment) for utilizing services over a multimedia network in response to the context and the requirements of a user (the state established by a user), is proposed. The DANSE treats uniformly all service‐constituting elements from hardware to software as network resources (NR), searches the NRs required for the user requirements and context during service execution and allocates them to a service environment by combining these. It proposes a substitute plan which corresponds to the context when no match is found for an NR required by the service required by the user. The user can thus utilize the service environment which combines NRs corresponding to the context without realizing it. In addition, the network can respond to the requirements of the user as much as possible by indicating a substitute plan even in a state in which the service contents could not be realized in the past. In addition, by using the mechanism of the DANSE, a service can be created and provided by specifying the service execution procedure, using the existing NRs. © 2001 Scripta Technica, Electron Comm Jpn Pt 2, 84(11): 30–40, 2001
Series connection of resonant tunneling diodes for eliminating spurious oscillations
Authors: Fujii Tetsu , Boric‐Lubecke Olga , Bae Jongsuck , Mizuno Koji
Published: August 2002

Resonant tunneling diodes, which have the highest operating frequencies among solid‐state oscillating devices at millimeter and submillimeter wave frequencies, generate spurious low‐frequency oscillations easily. As a method of suppressing spurious oscillation of negative resistance devices, the oscillation devices may be connected in series. In this paper, this approach is applied to resonant tunneling diodes. If two diodes are connected in series, no spurious oscillation is observed in the oscillation output spectrum. The effect of suppression of spurious oscillation is experimentally confirmed. Further, from the output characteristic, it is found that the devices are useful as low‐noise high‐ frequency amplifiers and frequency multipliers. © 2001 Scripta Technica, Electron Comm Jpn Pt 2, 84(12): 17–25, 2001
Information Criteria for Statistical Model Selection
Authors: Shibata Ritei
Published: August 2002

In regard to the selection criteria of various statistical models based on the Kullback–Leibler information content, their characteristics are compared and the importance of distinguishing the use in terms of the objective is pointed out. In regard to references dependent on the asymptotic approximation, it is pointed out by examples that the effectiveness of the approximation is important. In particular, as regards the model for discrete values, the necessity of estimation of the Kullback–Leibler information content is presented based on a method not dependent on an asymptotic approximation such as the bootstrap method. © 2001 Scripta Technica, Electron Comm Jpn Pt 3, 85(4): 32–38, 2002
Decomposition of periodic time‐varying transfer function into phase and amplitude modulation components
Authors: Okumura Makiko , Tanimoto Hiroshi
Published: August 2002

A nonlinear circuit with periodic operation, such as a mixer and oscillator, can be modeled as a linear periodic time‐varying circuit by assuming a small‐signal input and output. This paper presents a method by which the transfer function of such a periodic time‐varying circuit can be decomposed into phase and amplitude modulation components. Assuming a small input, the phase modulation component can be interpreted as a result of narrow‐band phase modulation with a small modulation index. Thus, it suffices to consider only the first sideband. As regards the spectrum of the amplitude modulated signal, it suffices to consider only the first sideband, regardless of the modulation index. Thus, the two spectra corresponding to the upper and lower sidebands around the carrier are decomposed into narrow‐band phase and amplitude modulation components, and the transfer function can be decomposed into phase and amplitude modulation components. By this method, it becomes possible to decompose the noise of the mixer and the oscillator into the amplitude noise and the phase, or to simulate AM‐PM conversion. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 85(7): 29–37, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.1105
A study of rotor configuration for IPMSM with concentrated winding considering the iron loss
Authors: Murakami Hiroshi , Honda Yukio , Morimoto Shigeo , Takeda Yoji
Published: August 2002

This paper reports an IPMSM rotor configuration with a concentrated‐winding stator. The inductance of the concentrated winding is greater than that of the distributed winding and the flux density of the concentrated winding contains higher harmonic components. The result is higher winding losses than in the IPMSM with a distributed‐winding stator. We discuss three types of interior magnetic rotor with different saliency ratios. In the lower speed range, the highest‐saliency rotor is effective in decreasing the load current and copper losses. On the other hand, in the higher speed range, the higher‐saliency rotors result in greater iron losses and lower motor efficiency; in this range, the lower‐saliency rotor is effective in decreasing iron losses and increasing motor efficiency. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 139(4): 71–78, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10005
An FDTD analysis of electromagnetic fields caused by electrostatic discharge between metals with ferrite material attachments
Authors: Fujiwara Osamu , Kawaguchi Kei
Published: August 2002

The transient electromagnetic fields due to electrostatic discharge (ESD) between charged metals have wide‐band frequency spectra up to the microwave region, which create a serious malfunction for high‐tech information devices. For the above ESD fields, we previously analyzed them, using the finite‐difference time‐domain (FDTD) method, and showed that the metals enhance the field level according to the metal dimension. From the standpoint of reducing such ESD fields, the electromagnetic fields caused by the spark between the metals with ferrite core attachments were investigated. The FDTD method was also used to compute the ESD fields. An FDTD algorithm for the magnetic field inside the ferrite core was newly derived. The results show that the cores attached near the spark gap considerably reduce the magnetic field level, which is also confirmed experimentally. © 2001 Scripta Technica, Electr Eng Jpn, 138(1): 34–41, 2002
New block diagrams using vector signals in the general frame of reference for AC motors with stator core losses
Authors: Shinnaka Shinji
Published: August 2002

This paper presents new block diagrams for induction and synchronous motors with stator core losses such as eddy‐current and hysteresis losses. The proposed block diagrams succeed in realizing simple and clear configurations with physically meaningful vector signals, which are helpful for understanding motor electromagnetic mechanism and useful for designing controllers for them. Vector signals, which are defined in the general reference frame, are utilized as transfer signals between blocks. The proposed vector‐signal block diagram in the frame can be directly and easily reduced to the one in such a specific frame as a stationary or synchronous frame simply by adding certain constraints to it. Shown are three configurations for induction motor, two for synchronous motors including permanent magnet cylindrical motor, permanent magnet salient‐pole motor, and reluctance motor. © 2001 Scripta Technica, Electr Eng Jpn, 138(2): 59–70, 2002
Properties of liquid jet induced by electrohydrodynamic pumping in dielectric liquids
Authors: Hanaoka Ryoichi , Takata Shinzo , Murakumo Masatoshi , Anzai Hidenobu
Published: August 2002

Liquid‐jet phenomena induced by electrohydrodynamical (EHD) pumping were investigated in isothermal dielectric liquids without direct charge injection at a metal/liquid interface. A pseudo‐doughnut to plane electrode system was used to generate an EHD liquid jet, and the liquid jet properties were measured using four different dielectric liquids (which are referred to as DBDN, BCRA, Tr‐Oil, and FS‐Oil in this paper). The maximum velocity and pumping pressure achieved were 1.5 m/s and 5.5 kPa, respectively, at an applied voltage of 23 kV with approximately 2.5 W of electrical power consumption in BCRA. It is considered that this liquid jet is due to pure conduction pumping. This mechanism is associated with heterocharge layers near the electrodes which are based on the process of dissociation and recombination of the electrolytic species. Furthermore, to obtain high directivity of the liquid jet, two special nozzles (herein referred to as a normal nozzle and spiral nozzle) were designed. A highly directed liquid jet was obtained using the spiral nozzle. In this case, the flow pattern was of a spiral structure. It is considered that this spiral jet is produced by both the Coanda effect and the nozzle shape (conical hole). © 2002 Scripta Technica, Electr Eng Jpn, 138(4): 1–9, 2002; DOI 10.1002/eej.1132
An architecture of small‐scaled neuro‐hardware using probabilistically coded pulse neurons
Authors: Kawashima Takeshi , Ishiguro Akio , Okuma Shigeru
Published: August 2002

In this paper, we present an architecture for neuro‐hardware that can be realized in circuits of far smaller scale than in the conventional approach. In order to reduce the scale of the circuits, the architecture employs a new method of computing the membrane potential and the sigmoidal function by encapsulating the probabilistic properties into the relative delay between two pulses. The proposed architecture makes it possible to integrate more than 100 neurons in the latest FPGA chip, which is a 13‐fold miniaturization compared to the conventional architecture. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 139(4): 48–55, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.1168
Imaging characteristics of a new magnetic microprobe with spatial differentiation property
Authors: Sasada Ichiro , Tomonari Toshio , Noda Tamotsu
Published: August 2002

A new type of magnetic microprobe by which surface anomalies of magnetic or conductive materials can be detected with enhanced spatial resolution and sensitivity is presented. The probe is fabricated using a pair of thin amorphous wires bent in a U‐shape, on each of which two identical copper wire coils are wound. Four identical coils are connected so as to make a bridge circuit, in which two positively coupled coils on the same wire core are placed on opposite sides of the bridge circuit (with positive mutual coupling). The characteristics of the new probe, including the point spread function (PSF), spatial resolution, and sensitivity, are compared with those of a Dahle microprobe having the same assembly but with the connections of the four coils changed. © 2001 Scripta Technica, Electr Eng Jpn, 135(2): 9–16, 2001
Psychological essentialism and the differential attribution of uniquely human emotions to ingroups and outgroups
Authors: Leyens Jacques‐Philippe , Rodriguez‐Perez Armando , Rodriguez‐Torres Ramon , Gaunt Ruth , Paladino Maria‐Paola , Vaes Jeroen , Demoulin Stéphanie
Published: August 2002

According to the psychological essentialism perspective, people tend to explain differences between groups by attributing them different essences. Given a pervasive ethnocentrism, this tendency implies that the human essence will be restricted to the ingroup whereas outgroups will receive a lesser degree of humanity. Therefore, it is argued that people attribute more uniquely human characteristics to the ingroup than to the outgroup. The present article focuses on secondary emotions that constitute such characteristics. Study 1 showed that members of high‐ and low‐status groups attribute more positive secondary emotions to the ingroup than to the outgroup. Study 2 verified that the differential attribution extended also to negative secondary emotions. No exemplars of emotions were provided in Study 3. Instead, participants had to estimate the means of two distributions of numbers that supposedly represented characteristics of the ingroup and of the outgroup. The results of this third experiment illustrated the reluctance to attribute secondary emotions to the outgroup. The findings are discussed from the perspective of psychological essentialism. Copyright © 2001 John Wiley & Sons, Ltd.
Effects of exposure to sexist humor on perceptions of normative tolerance of sexism
Authors: Ford Thomas E. , Wentzel Erin R. , Lorion Joli
Published: August 2002

The results of an experiment supported the hypotheses that (1) for men high in hostile sexism, exposure to sexist humor creates a perceived social norm of tolerance of sexism relative to exposure to nonhumorous sexist communication or neutral humor, and (2) due to this ‘relaxed’ normative standard in the context of sexist humor, men high in hostile sexism anticipated feeling less self‐directed negative affect upon imagining that they had behaved in a sexist manner. Finally, exposure to sexist humor did not affect the evaluative content of men's stereotypes of women relative to exposure to neutral humor or nonhumorous sexist communication for participants high or low in hostile sexism. Copyright © 2001 John Wiley & Sons, Ltd.
New directions in social comparison research
Authors: Buunk Bram P. , Mussweiler Thomas
Published: August 2002

This article notices that social comparison theory has developed from being a focused theoretical statement on the use of others for self‐evaluation into a lively and varied area of research encompassing many different paradigms, approaches and applications. A recent ‘renaissance’ in social comparison theory is described in which links were established with social comparison work from before Festinger's (1954) classic paper, and in which various new methods and theoretical models were developed. More recently, an ‘enlightment’ of social comparison theory seems to occur in which an integrative effort is made to link social comparison processes to more general principles that underlie our psychological functioning. Four trends in this enlightment are described: (1) the movement of social cognition to the centre stage of social comparison research; (2) the interest in more biological perspectives, including evolutionary theory; (3) the focus on the role of individual differences such as social comparison orientation (Gibbons & Buunk, 1999) in moderating the responses to social comparison; and (4) an emphasis on the social context of social comparisons, in particular the influence of social groups and social identity. Copyright © 2001 John Wiley & Sons, Ltd.