bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generation of review task sequences based on teaching‐material structures and learning progress
Authors: Yonezawa Nobuyoshi 
Published: July 2007

AbstractWhen two‐dimensionally structured teaching materials are rearranged into a one‐dimensional sequence according to the teaching strategy, it is called teaching task sequence. The teaching is executed by presenting the tasks in the order in this sequence.This paper considers the situation where a task arises in the teaching task sequence whereby the learner cannot understand and proposes an algorithm to generate the review task sequence so that the learner can understand the task as fast as possible. The review task sequence is derived from learning progress and the structure of the teaching material.The directional connection called influential strength is introduced between the nodes in the teaching material structure graph, and the structure of the teaching material composed of N nodes is described by a square influence matrix of N‐th order with the influential strength as the element. The review task sequence is a real‐valued sort, which is obtained by operating the teaching record matrix to the influence matrix representing the tree structure, not by tracing the directed edges of the graph.
Algorithm–oriented information‐processing education
Authors: Kusunoki Fusako , Miyauchi Arata , Ozawa Shinji 
Published: July 2007

AbstractRecently, information‐processing education has increasingly been called upon to teach problem analysis and solution skills. However, due to the burden of having to learn many programming language rules, beginners cannot adequately acquire these skills in conventional information‐processing education.This paper proposes algorithm‐oriented information‐processing education. First, to teach good algorithm style, algorithm teaching is separated from programming language instruction. To enable beginning students to study algorithms without knowing a programming language, the program analysis diagram (PAD) compiler and the PAD simulator are prepared as educational tools.It is believed that in this algorithm‐oriented curriculum students can learn problem analysis and solution skills and, as a result, will be able to write highly maintainable computer programs. A curriculum based on the suggestions from the authors' research was implemented for two years and yielded favorable results which are reported here.
Small love‐wave SAW resonators with very low capacitance ratio
Authors: Shimizu Hiroshi , Suzuki Yuji 
Published: July 2007

AbstractWhen a strip grating of periodic strips of Au, Ag, or Pt is produced on a rotated Y‐cut LiNbO3, a Love‐type surface wave with a high coupling (K2 > 30 percent) is formed and the reflection coefficient per strip is as large as several tens percent.In this paper, a small IDT resonator, with an extremely low capacitance ratio making use of the Love‐type surface wave, is studied theoretically and experimentally.First, the admittance characteristics of the IDT are studied by means of the mode‐coupling equation, which is determined by the dispersion characteristics derived from the Floquet theorem. It can be shown that the IDT exhibits resonant characteristics and the capacitance ratio is 2.4 – 2.7 if the number of pairs is more than 10.Next, an experiment was carried out by using a combination of the Y‐X LiNbO3 substrate and the Au electrodes. It is demonstrated that the resonator with a low‐capacitance ratio can be realized, as predicted by the theory. Further, rhombically weighted electrodes are proposed. It is confirmed that the spurious transverse mode and the spurious longitudinal mode can be suppressed simultaneously.
Synthesis of low‐sensitivity second‐order real digital filters using complex two‐port adapters
Authors: Murakoshi Nobuo , Nishihara Akinori , Watanabe Eiji 
Published: July 2007

AbstractIf complex coefficients are used in the realization of the real‐coefficient transfer function, the degree of freedom in the circuit construction is enhanced. This creates a possibility that a lower‐sensitivity filter can be realized than in the traditional low‐sensitivity filter using the real coefficients.This paper discusses a method to construct the second‐order real‐coefficient IIR filter using the complex two‐port adapter. First, by using the complex two‐port adapter, a method for circuit construction is proposed where the second‐order bandpass, lowpass, high‐pass, and asymmetrical bandstop transfer functions are realized.The proposed circuit can be realized with fewer number of multipliers than the conventional circuits using complex coefficients. Then a method is shown which selects the complex two‐port adapter according to the value of the real part of the coefficient of the complex multiplier.By this selection method, the circuit with the lowest sensitivity in regard to the real part can be realized without increasing the computational complexity for the circuit. Furthermore, a method is considered to reduce the sensitivity also for the imaginary part of the complex multiplier coefficient. Finally, using a simple example, it is verified that the circuit obtained by the proposed construction method has the low sensitivity.
Bifurcation set in a nonlinear compound system
Authors: Hirai Kazumasa , Adachi Tomohiko 
Published: July 2007

AbstractA bifurcation phenomenon may occur in a nonlinear system where the number of equilibrium points or their properties change by a small change of parameter. The set of parameters that can produce the bifurcation phenomenon is called the bifurcation set.In general, it is difficult to determine the bifurcation set when the order of the system is increased. However, when the linear part of the system can be transformed into the controllable canonical form, the determination of the bifurcation set for the higher‐order system can be reduced to that of the one‐dimensional system.This paper derives the method to determine the bifurcation set for the compound discrete‐time system based on that idea. First, a certain class of compound system composed of a series connection is considered and the kind of bifurcations that can be generated is analyzed. Then it is shown that the number of variables needed to determine the bifurcation set can be reduced to the number of decomposable subsystems in the case of a generally connected system.
Design of IIR digital filters with given magnitude specifications using allpass networks
Authors: Zhang Xi , Iwakura Hiroshi 
Published: July 2007

AbstractThis paper proposes a direct design method in the z‐domain for the IIR digital filter with a parallel structure composed of allpass networks with complex and real coefficients, with the specifications for the bandedge frequencies of the passband and stopband as well as the magnitude in the passband (or stopband).First, a filter composed of two allpass networks with conjugate complex coefficients is considered. Also, the phase difference characteristic between the two networks is considered. By specifying the phase difference error, the determination of the filter coefficients is reduced to the eigenvalue problem of the matrix using Remez' algorithm. The filter coefficients are determined from the eigenvector corresponding to the maximum eigenvalue. Then iterative calculation is executed to realize the equiripple characteristic, and the optimal solution is derived.Next, the relation between the phase difference errors and the magnitude errors is discussed and it is shown that the filter can be designed by the proposed method by specifying the absolute value of the magnitude error. The usefulness of the proposed method is shown by design examples. The filter based on two allpass networks with real coefficients is also considered, and it is shown that the filter can be designed by the same procedure by formulating the procedure for the sum and the difference of the filter coefficients.
Concatenated coding scheme with variable coding gain
Authors: Kojima Toshiharu , Fujimura Akinori , Miyake Makoto , Fujino Tadashi , Yoshida Hideo , Yamagishi Atsuhiro 
Published: July 2007

AbstractThe concatenated coding scheme using convolutional coding with Viterbi decoding for inner code and Reed‐Solomon (RS) code for outer codes is an attractive scheme that can achieve a coding gain larger than that of the convolutional coding with the Viterbi decoding scheme. Hence, it has attracted attention in a wide range of fields in satellite communications from space communications to digital image transmission systems.This paper presents the configuration and characteristics of a newly developed concatenated coding scheme with variable coding gain. This scheme enables selection of a coding gain considering the signal processing time of coding and decoding by enabling selection of: 1) the block length of the RS code (and its error‐correction capability); 2) the depth of interleaving combining the inner and outer code by a single codec. In addition, in this scheme, a new synchronization word detection method was developed and employed. In this method, nonlinear conversion is applied to soft decision demodulated data to synchronize the RS codeword and interleaving. It has been confirmed by numerical calculations that this synchronization word detection method has characteristics further improved over those of the conventional soft decision synchronization word detection method which is superior to the hard decision method. An experimental system was developed and the field test via Ka‐band satellite of communication satellite No. 3 (CS‐3) was performed, and the tradeoff relationships between the coding/decoding signal processing time and coding gain have been clarified quantitatively.
Bit error rate analysis of multilevel coding scheme and optimum error‐correcting capability assignment for impulsive noise
Authors: Kaneda Kazuyuki , Ogiwara Haruo 
Published: July 2007

AbstractThe advantage of the multilevel coding scheme is that the coding can be performed independently for each level, and the optimal coding can easily be determined for the channel with superposed noise with arbitrary probability density distribution. To evaluate the performance of this coding scheme, an approximate formula for the bit error rate after decoding is derived. As an example, the channel with the impulsive noise is considered. Using the approximate formula, the error‐correcting capability is assigned optimally to the levels and the coding gain of 20 dB is obtained for the BCH code of code length 31. The foregoing result is confirmed by a computer simulation. A report has already been proposed for the case where the errors of the decoder outputs are randomized except for the top level, by interleaving among the levels. However, a problem arises in that the delay as well as the circuit scale is increased. From such a viewpoint, this paper discusses the case without inter‐leaving. Finally, the performances are compared between the cases with and without interleaving among levels.
Optimal diagonal approximation of the covariance function with respect to the relative entropy using the wavelet basis
Authors: Sakaguchi Fuminori 
Published: July 2007

AbstractIf the covariance function of a random signal can be written in a diagonal form via the wavelet basis, this random signal can be regarded as a superposition of the wavelets which arise randomly. However, it is known that, in general, such an expression is not possible.In this paper, in place of a perfect diagonalization, an optimal approximate diagonalization in the sense of the relative entropy is investigated theoretically. Especially, it is shown that when a set of wavelets forming complete orthonormal sets (expressed in a vector form as {ϕi} is used as the basis, an optimal diagonal approximation of the covariance matrix Γ is not the diagonal form\documentclass{article}\pagestyle{empty}\begin{document}$ \sum\limits_k {\left({\bar \phi _k ^T \Gamma \phi _k} \right)} \phi _k \bar \phi _k ^T $\end{document}using the so‐called “wavelet spectrum” but\documentclass{article}\pagestyle{empty}\begin{document}$ \sum\limits_k {\left({\bar \phi _k ^T \Gamma ^{- 1} \phi _k} \right)^{- 1}} \phi _k \bar \phi _k ^T $\end{document}Further, several examples are given where Haar wavelets are used.
Immunopathology in schistosomiasis is controlled by antigen‐specific regulatory T cells primed in the presence of TLR2
Authors: Layland Laura E. , Rad Roland , Wagner Hermann , da Costa Clarissa U. Prazeres 
Published: July 2007

AbstractRegulatory T cells (Treg) are vital in maintaining the homeostasis of immune reactions. In chronic infections, such as schistosomiasis, it remains unclear whether engagement of the TLR family is required to induce Treg activity. Thus, we performed in vivo studies using TLR2–/– mice infected with Schistosoma mansoni and found elevated immunopathology, decreased egg burden and extended antigen‐specific Th1 responses. Simultaneously, the population of Treg failed to expand. To evaluate the role of Treg during infection, we functionally inactivated CD4+CD25+ T cells and observed that the resulting immunopathology mirrored that in TLR2–/– mice. Egg burden was also reduced in anti‐CD25‐treated mice, indicating that without Treg eggs are more efficiently destroyed. In addition, antigen‐specific T cells from both TLR2–/– and anti‐CD25‐treated mice displayed an extended Th1 phase. Finally, adoptive transfer of schistosome‐primed, but not naive CD4+CD25+ T cells was able to resolve the immunopathology in TLR2–/– recipients and interestingly, this amelioration was independent of TLR2 being present on the transferred Treg. We conclude that TLR2 is necessary for priming active Treg and their expansion during schistosomiasis.
Thermodynamics of Complexes between Dibenzo‐24‐crown‐8 Derivatives and 1,2‐Bis(pyridinium)ethanes
Authors: Liu Yu , Li Chun‐Ju , Zhang Heng‐Yi , Wang Li‐Hua , Li Xiao‐Yun 
Published: July 2007

AbstractThe binding behavior of para‐substituted 1,2‐bis(pyridinium)ethane derivatives (X‐PyCH2–CH2Py‐X, X = H, Me, Ph, and Py) a–d with dibenzo‐24‐crown‐8 (DB24C8, 1) and its derivatives, diformyldibenzo‐24‐crown‐8 (2), dinitrodibenzo‐24‐crown‐8 (3), dimethyldibenzo‐24‐crown‐8 (4) and diaminodibenzo‐24‐crown‐8 (5), has been comprehensively investigated by 1H NMR and UV absorption spectroscopy and isothermal titration microcalorimetry in acetonitrile. The results obtained indicated that some of the complexes constructed from DB24C8 derivatives and 1,2‐bis(pyridinium)ethane derivatives resulted in visible color changes. For example, upon the addition of equimolar proportions of 5, the colorless CH3CN solution of d changed to red. Furthermore, we investigated the thermodynamics of the complexation of crown ethers 1–5 with guests a–d, and found that the nature of the substituents attached to 1,2‐bis(pyridinium)ethanes and the catechol rings on DB24C8 dramatically affects the molecular recognition behavior and the binding thermodynamics. Thermodynamically, the formation of these complexes is an enthalpy‐driven process. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Copper‐Catalyzed Synthesis of 2,3‐Disubstituted Indoles
Authors: Tanimori Shinji , Ura Haruna , Kirihata Mitsunori 
Published: July 2007

AbstractThe copper‐catalyzed one‐step synthesis of 2,3‐disubstituted indoles from readily available starting materials, 2‐iodoaniline and various β‐keto esters was described. The advantage of this method is the use of cheap catalysts and simple experimental procedures under mild reaction conditions. As the substituted indole derivatives are important starting materials for the synthesis of biologically active indole alkaloids and drug candidates, this method would have potential usage for above purpose.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Patterns of decline and evidence of subgroups in patients with Alzheimer's disease taking galantamine for up to 48 months
Authors: Rockwood Kenneth , Dai Dingwei , Mitnitski Arnold 
Published: July 2007

AbstractBackgroundLacking long‐term placebo‐controlled trials of cholinesterase inhibitors (ChEIs) in Alzheimer's disease, how decline is modeled is crucial to interpreting the effects of long‐term, open‐label use. We aimed to: 1) understand changes in cognition and function in people taking galantamine; (2) identify treatment subgroups.MethodsThis is an open‐label long‐term extension (up to 48 months) of two placebo‐controlled clinical trials from Europe and Canada. At baseline, 240 patients with mild‐moderate Alzheimer's disease at baseline had received galantamine continuously for 36 months. The trajectory of scores on the Alzheimer's Disease Assessment Scale—Cognitive Subscale (ADAS‐Cog) and the Disability Assessment for Dementia (DAD) was modeled over 48 months. Goodness of fit was compared using normalized residuals and by calculating correlation coefficients between observed and fitted data. Iterative K‐means clustering identified subgroups.ResultsOf 240 patients, 51 (21%) withdrew between months 36–48 (nine died and 12 with adverse events). The mean ADAS‐Cog worsened from 22.6 (mean) ± 8.6 (SD) at baseline to 31.3 ± 3.1, with similar changes in the DAD. The logistic function fit better (ADAS‐Cog norm of residuals = 2.05, r = 0.993; DAD = 2.21, r = 0.998) than the commonly used Stern equation (ADAS‐Cog = 4.22, r = 0.944; DAD = 7.51, r = 0.986). K‐means clustering identified three stable groups; least decline (n = 82), persistent progression (n = 75), and an intermediate group (n = 82). Initial conditions were important: the mean ADAS‐Cog score for those with least decline was 15 ± 8, better than both the intermediate group (20 ± 9) and persistent progressors (30 ± 10; p < 0.001).ConclusionsAlzheimer's disease patients show variable long‐term decline that is best modeled as a logistic function, not as linear decline. Over 48 months, about one‐third of patients showed little decline, while one‐third showed important decline. Copyright © 2007 John Wiley & Sons, Ltd.
Does physical activity moderate the association between depressive symptoms and disability in older adults?
Authors: Lee Yunhwan , Park Kyunghye 
Published: July 2007

AbstractObjectiveDepressive symptoms and disability are closely associated and known to have reciprocal relationships. This study examines whether physical activity moderates the association between depressive symptoms and disability in community‐dwelling older adults.MethodsBaseline and 1‐year follow‐up data of 645 persons aged 65 years or older from the Suwon Longitudinal Aging Study were analyzed. A 15‐item Geriatric Depression Scale, Physical Functioning scale, and physical performance tests were used to assess the individual's depressive symptoms and functional disability. Physical activity was defined as the recommended level of exercise based on its frequency and intensity. Multiple regression analysis with generalized estimating equations was conducted to examine the physical activity's role as an effect modifier in the association between depressive symptoms and disability.ResultsPhysical activity was a significant effect modifier in the ‘depressive symptoms–disability’ association, controlling for sociodemographic characteristics and health‐related covariates. Moderate‐intensity activity was as effective as vigorous activity in moderating the relationship. The moderating effect was notable among those displaying severe depressive symptoms and functional disability. Over time the strength of the association between depressive symptoms and disability tended to diminish for those engaging in physical activity.ConclusionThe association between depressive symptoms and disability is moderated by physical activity in older persons. The findings suggest that healthcare professionals need to promote moderate amount of physical activity as a potential intervention tool in attenuating the depression–disability connection in later life, especially among those with high levels of physical and mental impairments. Copyright © 2007 John Wiley & Sons, Ltd.
Vascular disease and apathy in old age. The Leiden 85‐plus Study
Authors: van der Mast R. C. , Vinkers D. J. , Stek M. L. , Bek M. C. , Westendorp R. G. J. , Gussekloo J. , de Craen A. J. M. 
Published: July 2007

AbstractBackgroundApathy is defined as an important loss of motivation in all domains of daily functioning. Especially in old age, apathy might be a specific neuropsychiatric syndrome separate from depression. There are indications that apathy in elderly subjects is related to vascular disease.ObjectiveTo assess the relation between vascular disease and apathy in subjects aged 85 years and older.MethodsThe Leiden 85‐plus Study is a prospective, population‐based study of 500 elderly subjects. Vascular disease including myocardial infarction, angina pectoris or myocardial ischemia, claudicatio intermittens, and arterial surgery was determined at baseline. Symptoms of apathy were assessed annually from age 85 through 90 years using the apathy questions of the 15‐item Geriatric Depression Rating Scale (GDS). Diagnostic accuracy of the apathy questions was validated using the Apathy Scale at age 90 years. The association between vascular disease and apathy was estimated both at baseline and longitudinally.ResultsThe apathy items of the GDS showed a sensitivity of 69% and a specificity of 85%. At baseline, 69 subjects with apathy but free of depression had significantly more cardiovascular pathologies compared to 287 subjects without apathy. In the 287 subjects who were free of apathy and depression, increase of apathy but not depression during follow‐up was significantly higher for each additional cardiovascular pathology at baseline.ConclusionIn community dwelling elderly, those with vascular disease were at higher risk of developing apathy but not depression. This suggests that apathy and depression in old age have different etiologies. Copyright © 2007 John Wiley & Sons, Ltd.
Screening for elder abuse in dementia in the LASER‐AD study: prevalence, correlates and validation of instruments
Authors: Cooper Claudia , Manela Monica , Katona Cornelius , Livingston Gill 
Published: July 2007

AbstractBackgroundSeveral studies have investigated abusive behaviour by carers towards people with dementia, most using unvalidated scales; only two reported correlates of abuse after controlling for mediators and confounders, and these controlled for different factors.ObjectiveTo investigate the acceptability and validity of the Modified Conflict Tactics Scale (MCTS) and abuse correlates.MethodsEighty‐six people with Alzheimer's disease and their family carers, originally recruited for a representative community study were interviewed. We asked carers about acceptability of the MCTS and investigated its validity by comparing scores to the Minimum Data Set (MDS) abuse screen (an objective measure) and testing hypotheses that MCTS score would correlate with the COPE dysfunctional coping scale but not carer education.ResultsTwenty‐four (27.9%) were identified as abuse cases by interview. No care recipients (CRs) screened positive for abuse using the MDS screen. Seventy‐two (83.7%) participants thought that the scale was acceptable, ten (11.6%) that it was neither acceptable nor unacceptable, and three (3.5%) that it was unacceptable. As hypothesised, MCTS scores correlated with dysfunctional coping scale score but not carer education.ConclusionsThis is the most comprehensive study so far in this field. The MCTS was acceptable and had convergent and discriminant validity for measuring carer abuse. The MDS failed to identify cases of abuse. Carer male gender and burden, and greater CR irritability, cognitive impairment but less functional impairment predicted carer abusive behaviour. Our findings appear to refute UK government elder abuse reduction policy which assumes that few incidents of abuse arise from carer stress. Copyright © 2007 John Wiley & Sons, Ltd.