bluuebunny/crossref_metadata_2025 huggingface dataset:
A new approach to global routing for three‐metal‐layer gate arrays
Authors: Terai Masayuki , Sato Koji , Takahashi Kazuhiro , Matsuzaki Hideo
Published: July 2007

We propose a new global routing approach for three‐metal‐layer gate arrays. A gate array chip handled in this paper consists of rows of cells of a uniform height, megacells such as RAMs or ROMs, and routing channels. The proposed approach breaks the gate array chip into a two‐dimensional array of rectangular global routing cells (in short, G cells) by coarse grid lines and constructs global routes for all the nets on the array of G cells. The feature of our approach is that the capacities of G‐cell boundaries corresponding to routing channels are variable. Utilizing freedom in the capacities of G‐cell boundaries, our global routing algorithm changes the capacities at a certain stage of its execution and reduces the number of nets rerouted in the subsequent rerouting phase, in order to speed up the global routing process. The effectiveness of our approach is demonstrated by our experimental results on 400 K‐gate sea‐of‐gates array chips.
Automatic generation of command level simulation model of a processor from rt level description
Authors: Akaboshi Hiroki , Yasuura Hiroto
Published: July 2007

In designing a digital circuit with a microprocessor, there are several simulation levels. Using a logic synthesis tool and a layout synthesis tool, a lower‐level simulation model can be generated from a design RT level described in HDLs. There is trade‐off between accuracy and speed of simulations. A lower‐level simulation model can simulate more accurately. There is little support for generating high‐level simulation models in which a human designer is required. In this paper, an algorithm is proposed for high‐level simulation model generation and experimental results are shown.
Modeling and simulation analysis of indoor packet radio communication systems
Authors: Kasahara Hirokazu , Hara Shinsuke , Morinaga Norihiko
Published: July 2007

The characteristics of wireless channels are greatly different from those of wire channels. In wireless channels, the capture effect and hidden terminal problems occur. Therefore, it is important that the characteristics of wireless channels are modeled accurately and efficiently when analyzing the total system performance of wireless systems. In this paper, we model the spatial distribution of mobile terminals and base stations for an indoor packet radio communication system. We also model a radio propagation path in terms of Rayleigh fading, logarithmic normal shadowing, and propagation path loss. We then evaluate the packet reception success rate from the channel use, condition of the propagation path, the given modulation/demodulation method and media access protocol, using a bit error rate table. We show a method of analyzing the system characteristics (through‐put, packet success rate, and average delay time) efficiently using computer simulations. Also, as an example of numerical analysis, we create simulation for an indoor radio packet communication system using the direct sequence/spread spectrum (DS/SS) method and analyze its system characteristics.
Error detection of real‐number input fast fourier transform networks
Authors: Chen Song , Goto Munehiro
Published: July 2007

Fast Fourier transform (FFT) is one of the techniques indispensable in signal processing. the recent development of hardware and parallel processing techniques makes it possible to use a specific chip circuit for signal processing such as FFT and in fact there exist systems that achieve high‐speed computation of FFT. Such systems use many processors in a chip. Consequently, these are likely to have high error probability and require on‐line fault detection. This paper treats the fault‐detection methods of the FFT‐CN (FFT calculation network) under the assumptions that the FFT‐CN is made up ofN/2, x log2Ntwo‐input butterfly modules, that itsNinputs are all restricted to the real values, and that the detection of the fault is performed by the comparison of the outputs of the network. the assumed structure of the FFT‐CN is symmetric so a simple fault‐detection method would not be successful. But we will show here that the restriction of the inputs to real numbers makes it possible to find a fault in the FFT‐CN.
Characteristics of short‐term memory of tone duration in the human auditory system
Authors: Kanoh Shin'ichiro , Futami Ryoko , Hoshimiya Nozomu
Published: July 2007

Information for “tone duration” (duration information) is an important parameter in representing the temporal sequence. This paper reports on the results of a basic auditory psychophysical experiment which was executed in order to estimate how information is represented in the process to be perceived and retained in the brain. the experiment focuses on the “gradual change of the retained duration information,” which has been intentionally excluded in the past acoustic psychology, in order to focus on the perception process. the subject is instructed to compare the durations of two successively presented tones. the experiment demonstrated that the interval of uncertainty, which is the index of forgetting the retained information, depends on the duration of the first tone as well as the interstimulus interval between the two tones. It is then suggested that there exists a “duration which is especially easily forgotten.” A result is also obtained that is consistent with the conjecture that the presented duration information is handled almost as a continuous value in the brain. It is expected that those findings will provide a clue to the modeling of temporal sequence processing in the brain.
The minimum number of sliding operations of palettes in a two‐dimensional automatic warehouse of size N × M (N, M ≥ 3) with three spaces
Authors: Kawaguchi Kimio , Wu Jingjun , Wada Koichi , Aoki Hitoshi
Published: July 2007

To utilize fully a planar automatic warehouse with a specified area, a larger number of goods should be stored and shipped efficiently. Consider the situation in which a planar rectangular automatic warehouse has N × M sections and (NM‐k) palettes 1 × 1 in size. Then, k sections are produced which are spaces without a palette. In the shipping operation process, the palette already loaded with the desired good at the position (n, m) (0 ⩽ n ⩽ N −1, 0 ⩽ m ⩽ M −1) slides to the exit at position (0, 0) by utilizing the places where the good is unloaded. Considering the N × M automatic warehouse with k spaces, a problem is posed to determine the function T(k; n, m), which represents the minimum time (the minimum number of parallel sliding operations, called minimum steps) needed for a palette at position (n, m) to slide to the position (0, 0); T(1; n, m), T(2; n, m), and T(k; n, m) (k4) are already derived by past studies [1, 2], but the derivation of T(3; n, m) has not been achieved. the purpose of this paper is to present the solution for this problem for the case of N ≥ 3, M ≥ 3.
Estimation of stochastic model for random moving image by means of noncausal model
Authors: Miyagi Shigeyuki , Ogura Hisanao , Takahashi Nobuyuki
Published: July 2007

A new method for estimating a stochastic model of a random moving image is proposed. Assuming that the spatiotemporal spectrum of a moving image is separable in space and time, a stochastic image model is obtained by combining a noncausal model in two‐dimensional space and a causal AR model in time. Model estimation uses the method of minimizing whiteness for the noncausal spatial model and the method of “sequential orthogonalization” for the causal temporal model. the separable spectrum can be readily applied to a drifting moving model. Applying the spatial filter to a drifting moving image, the moving image is decomposed into a set of uncorrelated time series along the drifting time axis; this allows the AR models to be estimated separately. It is confirmed by computer simulation that the correct model can be estimated by this method. On the other hand, in the model estimation for a real, natural moving image, spectral separability is not always valid and, therefore, the output time series of the spatial filter is not rigorously uncorrelated. For such a real moving image, the method devised is an extended AR model which takes into account the spatially correlated data for AR model estimation. For estimating an extended AR model, the method of quasisequential orthogonalization is developed by modifying the sequential orthogonalization. It is successfully applied to processing a real moving image taken from a video recording.
A second‐order active bandpass filter with complex coefficients and its applications to the hilbert transform
Authors: Zhang Xiaoxing , Shinada Yuji
Published: July 2007

In this paper, the direct realization of a second‐order active bandpass filter with complex coefficients using operational amplifiers, resistors, and capacitors is proposed and its application to the Hilbert transform is discussed. Then, an active analytic signal converter is realized through real coefficient circuits that are required for signal processing with complex coefficients. Finally, examples of these realizations are presented. the feasibility of the proposed circuit is confirmed by the simulation results which are in good agreement with the theoretical values.
Dependability assessment methods for factory automation systems using safety index
Authors: Mineo Yoshiyuki , Suzuki Yoshihisa
Published: July 2007

To evaluate the dependability of systems from the viewpoint of human safety, the magnitude of accidents in addition to the probability of the occurrence of accidents must be taken into consideration. Also, it is essential to be able to cope with various levels of accidents consistently, not to set different criteria according to the system.

Research is underway to standardize the safety index and put it to practical use as a criterion to quantitatively decide the dependability of the systems from the viewpoint of safety for people. However, as the safety index had the defect of being unable to represent the magnitude of accidents, its use as an index for evaluation was limited. to overcome this problem, this paper shows that the tree analysis for safety (TAS), which is a combination of the fault‐tree analysis (FTA) and human effectiveness, can be classified by factors of physical accidents such as high‐velocity machinery or high‐temperature substances. A method of evaluating such safety indices according to the criteria classified by the potential of the factors of physical accidents is proposed. By applying this method to examples of factory automation (FA) system accidents, whose patterns are seven at normal operation and four at maintenance, it is effective as a practical system evaluation method.
Stability‐guaranteed adaptive algorithm and its application to active noise canceling
Authors: Ojiro Naotaka , Kajiki Makoto , Ohmori Hiromitsu , Sano Akira , Tsujii Hiroyuki
Published: July 2007

There are some cases where feedforward control can be utilized effectively, e.g., the active noise control and the vibration control of a building. When there exists an indeterministic factor or a fluctuation, the adaptive filter must be introduced. the algorithm that adjusts the coefficient of the adaptive filter has mostly been based on the filtered‐x algorithm. A problem in this approach, however, is that the stability is not guaranteed and the stepwidth of least‐mean square (LMS) algorithm must carefully be determined.

From such a viewpoint, this paper proposes the adaptive algorithm both in the time and the frequency domains, where an arbitrary stepwidth can be used, and the robust stability is guaranteed even if an additive noise is mixed. As the first step, the infinite impulse response (IIR) adaptive filter is considered, aiming at implementation of the controller in the time domain, and the properties of the adaptive algorithm are analyzed. Then, the adaptive algorithm in the frequency domain is proposed where the controller is implemented using the frequency‐sampling filter and the stability is guaranteed.

In contrast to the case of the design in the time domain, the implementation in the frequency domain has the advantage that the realization is ensured independently of the order or the structure. Finally, the usefulness of the proposed adaptive algorithm is demonstrated by numerical example and experiment in the active noise canceler.
Representation and detection of multiscale, multiorientation fields using local differentiation filters
Authors: Shizawa Masahiko , Iso Toshiki
Published: July 2007

A basic theory is proposed for detecting multiorientation fields from images that have multiple orientations at each point in the field. This theory, representing a multiorientation field by a single set of fundamental constraint equations, differs from conventional methods which use many filters tuned to different orientations. It is also different from the steerable filters proposed by Freeman and Adelson [12]. This theory renders implementation of a selection process of orientation‐tuned filters with high‐magnitude output unnecessary. It also makes it unnecessary to implement a search process for an extreme value output of steerable filters. This theory lets analytical solutions to be derived that explicitly compute multiple orientations. This theory is derived from the operational formalism of the principle of linear superposition. Conventional methods suffer from interference between component signals when multiorientation signal components fall in the tuning range of each filter. As a result, filters with a narrow tuning range are necessary in conventional methods. the algorithms derived from out theory are not negatively influenced by interference. By using these algorithms in multiscale image representation, characteristic image structures such as junctions can be extracted from low‐order image derivatives. This theory is expected to provide a theoretical foundation for the image representation of multiple orientations of the hypercolumn structure in the primary visual cortex of the brain.
Maximum‐weight‐window problem of a planar graph
Authors: Yamaguchi Kazuaki , Kotani Ken , Masuda Sumio , Kashiwabara Toshinobu
Published: July 2007

When a planar graph is drawn, the drawing plane is divided into several regions, each of which is called a face. A subgraph composing the periphery of a face is called a window. For each window W that exists in the drawing of a planar graph G, the total sum of the weights of the vertices and the edges is called the weight of the window W. Among all windows that can appear in drawings, the window with the maximum weight is called the maximum‐weight‐window of G.

This paper considers the problem of determining the drawing with the maximum‐weight‐window. the result for this problem is already obtained for the case where the graph is 2‐connected, as well as for the case where the graph is not necessarily 2‐connected but all weights are nonnegative. This paper considers also the arbitrary planar graph with real‐valued weights, and shows that the drawing with the maximum‐weight‐window can be determined in O(n + e) time. This result can be applied to the layout design for LSI and printed board, as well as to the diagram representation of the network. It can also be applied to the solution of the maximal planarization problem for the graph.
An efficient approach for finding all solutions based on submatrix estimation
Authors: Kinoshita Hidetoshi , Asai Hideki
Published: July 2007

Finding all solutions based on the piecewise‐linear search is one of the steadiest methods to solve the nonlinear equation. A feature of the method is that the local convergence problem is not involved. On the other hand, the number of region searches required even for a smallscale problem is tremendous.

This paper proposes an efficient method for finding all solutions, restricting the problem to the anlayis of bipolar circuits. Based on the range of values that each variable can take and the liearity of the equation, the solution candidate regions are restricted by evaluating the existence possibility of the solution for each of the multiple subset variables. the submatrix is considered and the size is varied, and the efficiency of the solution search is improved by testing a large number of linear regions at the same time.

The proposed method works especially effectively when the signal propagation in the circuit has a directivity or the subcircuits have high independencies. Finally, the effectiveness of the proposed method is shown through actual compution exemples.
An adaptive algorthm based on nonuniform resolution filter
Authors: Naito Yukihiro , Tokuda Keiichi , Keneko Mineo
Published: July 2007

Recently, in acoustic and audio engineering where wideband signals are handled, it has become required to realize a large‐scale adaptive filter by small computational complexity. This paper proposes an efficient adaptive filter, based on the time‐frequency characteristics of the impulse response of the unknown system.

First, the filter structure is shown which can extract the time‐frequency characterstics of the impulse response of the unknown system. Then a nonuniform resolution filter is proposed which can represent the impulse response in the time‐frequency domain with a nonuniform resolution by allocating a small number of tap coefficients. an adaptive algorithm based on the proposed filter structure is derived. Finally, it is shown by a simulation that the computational complexity can be reduced by the proposed method when the unknown system has a nonuniform structrue in the time‐frequency domain.
Relationships between physical traits and subjective impressions of faces ‐ age and gender information
Authors: Yamaguchi Masami K. , Kato Takashi , Akamatsu Shigeru
Published: July 2007

This article presents two studies investigating the relationships between physical measurements and psychological judgments of human faces. The first study is concerned with gender and age classification, the second with femininity‐masculinity and childlike‐adultlike judgments of Japanese faces. The results indicate that (1) faces can be accurately classified into age categories based on physical measurements, (2) whereas age classification depends on the global information of a face, gender classification depends on its local information and (3) the femininity‐masculinity judgment of male faces tends to be made on the basis of age information. The authors relate these results to the processing of KANSEI‐information of, or subjective feelings about, a biological stimulus.
Adaptability of K‐L expansion technique for ambiguous face image retrieval
Authors: Oda Masaomi , Akamatsu Sigeru , Fukamachi Hideo
Published: July 2007

Some facial images are not necessarily clear images in the human brain. However, it can be easily judged whether a face matches the image in our mind; this is true even when the drawing or the expression of the target image is difficult to comprehend. This is because even if the image cannot be imagined like a picture, it does exist. the authors have proposed a system with which a retriever can retrieve an ambiguous target image from an image database. the system's retrieval efficiency and ease‐of‐retrieval were clarified by experiments using line‐drawn facial images. In this paper, the system is extended to photographs of faces. the most difficult problem in treating photographs is determining the retrieval key. One consideration is to add the subjective impressions or features of physical figures as keywords for each image data. Regardless of the method, however, significant manpower is necessary. the K‐L expansion technique is used here, which has been verified as effective for face identification, and expect to need only a small amount of manpower. This paper investigates whether the technique can also be useful in ambiguous image retrieval.
Color coordinate supporting system with navigating state of user's mind
Authors: Yagyu Tomohiko , Hisamori Yosihiko , Yagi Yasushi , Yachida Masahiko
Published: July 2007

A Color Coordinate Supporting System is proposed for detecting color coordination that matches a current state of user's mind from the design database through communication between a user and a computer. First, the user selects a few keywords, and the system extracts the initial candidates of color coordination from the design database that corresponds to the keywords. Next, these initial candidates are narrowed down to candidates adapting to the state of the user's mind. the user can com‐municate his candidate's preference to the computer. This result is recorded in the user's personal database, which then reference. Finally, the most favorite design is decided by Pair Comparisons. In Pair Comparison, the system changes the balance of color coordination with the user's preference database. Thus, the user can retrieve his/her most favorite design.
Realization of 3‐D adaptive separable‐denominator state‐space filters suitable for parallel processing
Authors: Muneyasu Mitsuji , Ishizaki Naoya , Hinamoto Takao
Published: July 2007

This paper introduces the parallel processing into the separable‐denominator 3‐D adaptive state‐space filter, and discusses a realization method which is suited to the high‐speed processing. the LMS (least‐mean‐square) algorithm is used as the adaptive algorithm, and the parallel processing‐oriented structure of the separable‐denominator 3‐D filter is used as the filter model.

The parallel processing‐oriented structure of the 3‐D adaptive state‐space filter is obtained by extending the adaptive algorithm of the 2‐D state‐space adaptive filter to the above 3‐D structure. the proposed algorithm is evaluated in this paper in terms of the time required for the filtering and the coefficient update, as well as the number of multipliers (adders). Finally, the proposed adaptive filter is applied to the design of the 3‐D state‐space digital filter, and the effectiveness of the algorithm is demonstrated.
Two‐phase controlled switched‐capacitor inductance simulation circuits using one second‐generation current conveyor (CC II)
Authors: Ono Toshio
Published: July 2007

Recently, second‐generation current conveyors (CC II) have been used widely in various analog circuits to simplify the circuits and to develop new circuits. However, there have been few reports on the application of CC to element level switched capacitor (SC) simulation.

This paper reports the development of an SC inductance simulation circuit using CC II, which is one of the complex cases of element level SC simulation. the proposed circuit uses one CC II active element and is operated by a two‐phase clock. the circuit has a smaller number of switches, capacitors, spread of capacitor values, and sum of capacitor values compared to the previously reported two‐phase controlled circuits using a single operational amplifier or a voltage follower; and the circuit configuration also is simpler. Moreover, its basic operation is confirmed by discrete components and the effect of parasitic capacitance is described.
Fundamental theory of natural observation method with complete reconstruction property by finite sum‐natural observation theory of normal type
Authors: Iijima Taizo , Iwaki Mamoru
Published: July 2007

A theory of natural observation methods was originally formulated for two complementary systems: neighboring type and equilibrium type. This paper introduces a new system, normal‐type system, that is different from the forementioned two types. One characteristic feature of the normal‐type natural observation method is its ability to reconstruct an original waveform from the sum of a finite number of observation values. the natural observation theory of a normal type evolves naturally under the condition that a waveform and its power component can be expressed in the sum form. These meanings are discussed by comparing a frequency response of the normal‐type natural observation transform with that of a conventional filter bank. Further more, a criterion for determining observation parameters in order to realize the natural observation of normal type under a given tolerance of error is described. It is believed that the proposed theory offers new insights into systematization of the natural observation theory.
Adaptive spectrum estimation considering the time variation in analysis intervals
Authors: Nakagaki Atsushi , Shibata Koji , Miyanaga Yoshikazu , Tochinai Koji
Published: July 2007

In spectrum estimation of nonstationnary signals, the modeling of time‐varying characteristics and the parameter estimation of the model are important. Several adaptive estimation methods such as the recursive least‐squares (RLS) method are often used for parameter estimation of time‐varying models. However, the RLS method becomes less efficient for rapidly time‐varying models because this method assumes short‐time stationarity. This paper proposes an adaptive estimation method of time‐varying parameters modeled as linear combinations of a set of basis functions. In this method, linear or exponential time functions. In this method, linear or exponential time functions are employed as basis functions. This algorithm is relaized by the RLS algorithm with a rectangular window and a procedure that shifts basis functions. In some experiments, the performance of the proposed method is compared with that of the conventional method with short‐time stationarity assumed.
Quasi‐synchronous code division multiple access (CDMA) with binary shift‐register sequences
Authors: Kuno Seiji , Yamazato Takaya , Katayama Masaaki , Ogawa Akira
Published: July 2007

This paper discusses the quasi‐synchronous code‐division multiple access system (QS‐CDMA), where the time error in the synchronized access is allowed for a certain range, based on the spread‐spectrum communication technique. the Gold sequence and the M sequence, which are the binary shift‐register sequences, are used to derive the set of quasi‐synchronous spread sequences (QS‐sequence) considering the auto‐ and cross‐correlation characteristics, realizing a wide tolerable range for the timing error.

The QS‐CDMA system using such QS‐sequence is investigated, and the effectiveness is examined. As a result, it is seen that the performance is improved greatly by using the QS‐sequence presented in this paper, compared to the asynchronous CDMA system. It is shown also that the tolerable range for the access timing error is enlarged compared to the synchronous CDMA system.
Two‐dimensional neural hybrid filters using adaptive windows and layered median filters
Authors: Muneyasu Mitsuji , Maeda Takahiro , Hinamoto Takao
Published: July 2007

A new 2‐D neural hybrid filter tha combines a layered median filter with adaptive‐window linear filters is described. the filter can eliminate both impulsive and Gaussian noise and has good edge preservation characteristics, owing in particular to the 3‐point layered median filter design. the size of the adaptive windows is maximized in regions where the neighboring pixel values differ relatively little from that at the working point. the design yields effective noise removal without edge degradation, and learning by the neural network allows the filter to adapt to image characteristics.
Field investigation on rilling in the experimental Sparacia area, South Italy
Authors: Bruno Carmelo , Stefano Costanza Di , Ferro Vito
Published: July 2007

In this paper the results of a field investigation on rilling carried out in the experimental Sparacia area are reported.

The measurements were made on a plot 6 m wide and 22 m long subjected to natural rainfalls. For ten rainfalls the total soil loss (interrill and rill erosion) was collected in a storage system consisting of two tanks arranged in series at the base of the plot. Rill morphology (rill length and cross‐sections) was measured for five rainfall events, while the rill profile was surveyed for three events.

First the contribution of each component (rill and interrill erosion) to total soil loss was established. Then the analysis allowed establishment of a power relationship between the rill length and the rill volume. Finally, for three events detailed information on rill erosion and rill morphology allowed verification of the applicability of WEPP and estimation of the rill erodibility constant. Copyright © 2007 John Wiley & Sons, Ltd.
Nitric oxide‐induced apoptosis in cultured rat astrocytes: Protection by edaravone, a radical scavenger
Authors: Kawasaki Toshiyuki , Kitao Tatsuya , Nakagawa Katsuhiro , Fujisaki Hiroko , Takegawa Yoshimi , Koda Ken , Ago Yukio , Baba Akemichi , Matsuda Toshio
Published: July 2007

Nitric oxide induces apoptosis‐like cell death in cultured astrocytes, but the exact mechanism is not known. This study further characterized the mechanism of nitric oxide‐induced cytotoxicity, and examined the effect of edaravone, a radical scavenger, on cytotoxicity. Treatment of cultured rat astrocytes with sodium nitroprusside (SNP), a nitric oxide donor, for 72 h, decreased cell viability by causing apoptosis‐like cell death. The injury was accompanied by increases in the production of reactive oxygen species and in the level of nuclear apoptosis‐inducing factor, but not in caspase activity. SNP‐induced cytotoxicity was blocked by the c‐jun N‐terminal protein kinase (JNK) inhibitor SP600125 (20 μM), the p38 mitogen‐activated protein (MAP) kinase inhibitor SB203580 (20 μM), and the extracellular signal‐regulating kinase (ERK) inhibitor U0126 (10 μM), and the nitric oxide donor stimulated the phosphorylation of p38 MAP kinase, JNK, and ERK. Edaravone (10 μM) protected astrocytes against SNP‐induced cell injury and it inhibited SNP‐induced phosphorylation of p38 MAP kinase, JNK, and ERK, and the production of reactive oxygen species. Edaravone also attenuated SNP‐induced increase in nuclear apoptosis‐inducing factor levels. These results suggest that MAP kinase pathways play a key role in nitric oxide‐induced apoptosis and that edaravone protects against nitric oxide‐induced cytotoxicity by inhibiting nitric oxide‐induced MAP kinase activation in astrocytes. © 2007 Wiley‐Liss, Inc.
Astrocytes—Friends or foes in multiple sclerosis?
Authors: Williams Anna , Piaton Gabrièle , Lubetzki Catherine
Published: July 2007

In multiple sclerosis (MS), the presence of demyelinating plaques has concentrated researchers' minds on the role of the oligodendrocyte in its pathophysiology. Recently, with the rediscovery of early and widespread loss of axons in the disease, new emphasis has been put on the role of axons and axon‐oligodendrocyte interactions in MS. Despite the fact that, in 1904, Müller claimed that MS was a disease of astrocytes, more recently, astrocytes have taken a back seat, except as the cells that form the final glial scar after all hope of demyelination is over. However, perhaps it is time for the return of the astrocyte to popularity in the pathogenesis of MS, with recent reports on the dual role of astrocytes in aiding degeneration and demyelination, by promoting inflammation, damage of oligodendrocytes and axons, and glial scarring, but also in creating a permissive environment for remyelination by their action on oligodendrocyte precursor migration, oligodendrocyte proliferation, and differentiation. We review these findings to try to provide a cogent view of astrocytes in the pathology of MS. © 2007 Wiley‐Liss, Inc.
Increased gallstone risk in humans conferred by common variant of hepatic ATP-binding cassette transporter for cholesterol
Authors: Grünhage Frank , Acalovschi Monica , Tirziu Simona , Walier Maja , Wienker Thomas F. , Ciocan Anca , Mosteanu Ofelia , Sauerbruch Tilman , Lammert Frank
Published: July 2007

Genomewide scans of inbred strains of mice have linked the genes encoding the hepatocanalicular cholesterol transporter ABCG5/G8 to gallstone formation. Five nonsynonymous coding single-nucleotide polymorphisms (SNPs) in the orthologous human genes are associated with differences in serum cholesterol and plant sterol levels. We now tested these

ABCG5/G8

SNPs for linkage and association with gallstone susceptibility in humans. Prospectively, we collected data from 178 white individuals with gallbladder stones or history of cholecystectomy in 84 families and from 70 stone-free controls, as confirmed by abdominal ultrasound. We performed nonparametric linkage (NPL) analysis of affected sib pairs (ASPs) and association tests of cases and controls. In ASPs, gallstones were strongly linked to the D19H variant of the

ABCG8

gene (NPL score = 7.1;

P

= 4.6 × 10−13). The risk of gallstones in carriers of the 19H allele was significantly increased in randomly selected cases from the ASP cohort compared to the stone-free controls (OR = 3.018;

P

= 0.017). Consistent with the mouse model, heterozygosity for the lithogenic

ABCG8

allele was associated with gallstones in humans; 21.4% of gallstone patients carried the heterozygous D19H genotype, compared with 8.6% of controls (OR = 2.954;

P

= 0.026).

Conclusion:

The linkage and association studies identified the cholesterol transporter

ABCG5/G8

as a genetic determinant of gallstone formation, or

LITH

gene, in humans. The function of this transporter and the results of the genetic study taken together indicate that in gallstone-susceptible carriers of the

ABCG8

19H allele, cholesterol cholelithiasis is secondary to increased hepatobiliary cholesterol secretion. (Hepatology 2007.)
Design of work and technology in manufacturing
Authors: Brödner Peter
Published: July 2007

Due to profound changes in the world markets, the traditional structures of production and new market requirements have recently begun to contradict one another. The factory stands at the crossroads of technology‐ and human‐centered production concepts. In view of this radical change, designers must develop appropriate production systems as integrated wholes, taking into account the mutual dependencies between skills, organization, and technology, rather than install high‐tech systems only. This has been demonstrated by two recent developments (order control for production islands and shop‐floor programming methods) in the context of integrated group manufacturing as a human‐centered production concept.
Towards the model human scheduler
Authors: Sanderson Penelope M.
Published: July 2007

This article presents a framework for understanding and modeling the human operator when performing scheduling functions. The eventual goal is to build a complete model of the human scheduler, which will be termed theModel Human Scheduler(MHS). Presented is a framework for the MHS based on Rasmussen's (1986) decision ladder. This framework consists of a collection of 27 production rules which link different types of scheduling activities, from skill‐based through rule‐based to knowledge‐based activities. The framework defines the task that lies ahead if we are to achieve a fully computational MHS. The MHS incorporates Card, Moran, and Newell's (1986)Model Human Processor(MHP) as a computational operationalization of just one of the 27 production rules. An example is given of how the MHP can describe, in detail, the process of planning a sequence of steps according to the Moore‐Hodgson dispatch rule. This is the first step in developing the full model, and it starts to define an appropriate program of empirical research to support the modeling effort.
Using employee participation to implement advanced manufacturing technology
Authors: Levi Daniel J. , Slem Charles M. , Young Andrew
Published: July 2007

The implementation of advanced manufacturing technology (AMT) often requires a shift to teamwork. How should a company make this transition to team‐oriented AMT? Companies can let technology be the driving force and organize teams after the change process, or they can create teams and use employee participation to implement the technology. This study examined the attitudes of employees in five electronics companies which shifted to team‐based AMT. Employees in the companies which used employee participation to help implement the technological changes had more positive beliefs about their companies' ability to manage technological change. They were also more likely to believe that technological changes would help their careers and improve their jobs, and less likely to experience job insecurity and job stress due to technological change.
Personal Perspective: Critical human factors contributions in modern manufacturing
Authors: Wilson John R.
Published: July 2007

The roles of all personnel in manufacturing companies are changing as different forms of advanced technology and different methods of organizing production are introduced. There is some degree of freedom in defining these roles, and there is increasing recognition of the gains to be had from developing systems around the concept of the skilled, responsible operator with local control. In consequence, there is increasing recognition in industry of the input that can be made by the human factors profession. A number of critical human factors issues for modern manufacturing are identified in this article; these are critical both in terms of the relevant research gaps and application needs. Connections are drawn between these issues. Successful human factors initiatives in advanced manufacturing technology will only result from integration of approaches from the hitherto somewhat separate worlds of cognitive ergonomics as applied to human‐machine systems, and psycho‐social ergonomics as applied to work organization and job design.
Computer support for cooperative work in advanced manufacturing
Authors: Schmidt Kjeld
Published: July 2007

In order to prevail in the emerging turbulent business environment, the work organization of advanced manufacturing must be able to adapt diligently and dynamically to the vicissitudes of a volatile market. Meeting this demand requires horizontal exchange of information within a self‐organizing cooperative ensemble of decision makers with a high degree of autonomy in their strategies and conceptualizations. Advanced manufacturing, therefore, poses new demands on the information system of the enterprise that are not addressed in the prevailing approach to computer‐integrated manufacturing.
From machine‐centered to human‐centered manufacture
Authors: Dawson Patrick
Published: July 2007

This article provides a case study analysis of the process of transition from a traditional machine‐centered job‐shop working environment to a human‐centered manufacturing facility at a hardware fabrication plant in South Australia. The origination, design, and implementation of cellular manufacturing is examined, and the consequences of change for the organization and control of work is critically appraised. Employees operating under the new system take greater responsibility for their work performance and positively appraise the practice of cellular manufacture.
Representing organizational behavior in a bayesian belief network, and making the resulting inferences accessible to users
Authors: Toth‐Fejel T. T. , Clark S. J. , Kindrick J. D.
Published: July 2007

This article describes work on Dr. FactoryTM, a manufacturing plant diagnosis application, and Cause‐MICTM, an expert system shell on which it is based. The Dr. FactoryTMand Cause‐MICTMsystems are described in detail, followed by a description of how a knowledge‐based system can represent organizational behavior in terms of important concepts and their functional relationships. This article explains how domain experts increased their understanding of the knowledge they thought they knew, and how the results of the computation of Bayesian Belief Networks can be presented to users.
Organization design for factory 2000
Authors: Bessant John , Levy Paul , Ley Clive , Smith Stuart , Tranfield David
Published: July 2007

Evidence suggests that the effective implementation of advanced computer‐integrated technologies in manufacturing depends upon a considerable degree of organizational adaptation. One interpretation of such radical technological change suggests that it is part of a pervasive paradigm shift which is reframing the rules governing best practice in manufacturing and that organization design needs to involve a complete reappraisal rather than a minor adjustment. This article reviews evidence for the emergence of such a paradigm shift and presents some case study data on the nature of organizational changes which characterize it. It concludes with some suggested guidelines for organization designers working toward suitable models for factory organization and management into the next century.
The dual design approach as a tool for the interdisciplinary design of human‐centered systems
Authors: Bohnhoff Armin , Brandt Dietrich , Henning Klaus
Published: July 2007

During recent years, developments in production seem to have shown a strong orientation toward finding the best technical solution to a problem. Frequently, there has been little consideration of people concerned. This approach may be called “technocentric.” In contrast to this approach, it may be feasible to look for solutions which balance the advantages of a merely technical solution, and the skills and competencies of people. Systems of this latter kind may be called “human‐centered.” Such systems support flexible production processes based on skill‐based workplaces and group work, and they are embedded into flat hierarchical structures in industry. They are increasingly considered viable in economic terms. This article discusses the concept of human‐centered systems in some detail. It suggests the dual design approach as a tool to design such systems.
Societal embedding of production and inventory control systems: American and japanese influences on adaptive implementation in britain
Authors: Clark Peter , Newell Sue
Published: July 2007

Production and inventory control systems as steering and monitoring mechanisms were formalized at an early stage in large American firms. The shape and use of these systems contains many core features which are identifiably American and reflect their societal embedding. These core features are evident in their contemporary variants. When the systems were transferred to Japan, key elements of the core were repositioned to create an alternative template of corporate coordination. In Britain their adaptive implementation is impeded by the competing templates of international best practice and by the structured inability to create a relevant blending of the available elements.
Implementation of CIM technology: The key role of organizational learning
Authors: Lei David , Goldhar Joel D.
Published: July 2007

This article develops a conceptual model by which to examine the relationship between effective implementation of CIM technology with different levels and characteristics of organizational learning. Although a large number of firms have invested enormous sums into CIM and other advanced manufacturing technologies recently, many have not been able to garner the full potential of these investments to produce high variety at low cost. This article contends that successful implementation and utilization of CIM require a commensurate organizational commitment to instill double‐loop learning in which experimentation, risk‐taking, and an open‐systems perspective become the basis for redesigning organizational structures, reward systems, and human resource practices. Firms that are locked into patterns of single‐loop learning in which organizational change is resisted face the greatest difficulties in making the transition from traditional to advanced manufacturing technologies.
Management of technology, corporate culture and educational paradigms: Lessons from a case study
Authors: Manders André J. C.
Published: July 2007

This article discusses the relationship between the behavior of Research and Development management, and corporate culture and general socialization processes. It shows that, on the one hand, managerial attitudes are the product of corporate culture and socialization processes and, on the other, that management significantly contributes to their legitimation. This aspect of management behavior raises some questions. The analysis of these attitudes reveals that at least to a degree they have an economically debilitating effect. It is argued in this article that Research and Development management attitudes are a block on the road to solve a well‐known management problem, namely of finding an equilibrium between stimulating individual creativity and organizing effective cooperation. In support of this proposition the results of a case study are presented in which the decision‐making process about production technology at the Center for Manufacturing Technology is analyzed. The CMT is a Research and Development department of Philips Electronics Corporation in The Netherlands. First, the article elaborates the major elements of the Philips corporate culture, and the characteristics of the ruling educational paradigm at Dutch Technical Universities. With regard to the Philips culture the following factors are dealt with: the historical background of the Research and Development department and the related ambiguity of its position, the autonomy of the researcher, the industrial background of the R&D manager, the impact of personal commitment for successful research, skepticism about the quality of the intermediate goods supplied by the company, and disciplinary chauvinism. In addition attention is given to the “frame of existing solutions” (Sinclair), the close relationship between university and industry and the emphasis on “personal achievement” which are characteristic of the mainstream educational paradigm at Dutch technical universities. Second, the management behavior of the Philips Center for Manufacturing Technology department is described from the point of view of corporate culture to illustrate how the attitudes of CMT management contribute to the corporate culture in the enterprise and to the dominating technological paradigm, and how these attitudes detract from successful Research and Development activities.
An empirical study of hybrid inspection systems and allocation of inspection functions
Authors: Hou Tung‐Hsu , And Drury Li Lin Colin G.
Published: July 2007

With the demand for zero‐defect products and the requirement of shorter lead‐time production, designs of inspection systems have changed from using sampling inspection and human inspectors to 100% inspection and automated inspection systems. Unfortunately, automated inspection systems usually cannot meet the required performance without some human intervention. The objectives of this research are to demonstrate the feasibility of hybrid inspection systems, to compare these systems with the unaided human system and unaided automated inspection systems, and to develop a framework to allocate humans and computers in an inspection system in order to achieve the best system performance. This research found that a hybrid inspection system had better performance than either human inspection or entirely automated inspection systems. A proposed function allocation procedure was found to be feasible.
Survey of robot safety in industry
Authors: Hirschfeld R. A. , Aghazadeh F. , Chapleski R. C.
Published: July 2007

A questionnaire was mailed to 55 industrial robot users in the United States to determine what safety measures were used in the field. Nineteen companies using a total of over 580 robots responded to the survey. The questionnaire investigated types of robots, types of safety devices, optimal work range, ability to enclose, and response to error condition. Only 20% of robots were found to be completely enclosed, while 60% had a limited barrier or no barrier. Active safety measures such as light curtains and floor mats were found to be the most widely used safety devices at 67% and 59%, respectively. In addition, industrial users demonstrated poor conformance to the Occupational Safety and Health Administration (OSHA) regulations and to the American National Standards Institute/Robot Industries Association (ANSI/RIA) standards.