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Kinds of Bit Terms modified by Bit Selected AbstractsDesign, analysis, and synthesis of generalized single step single solve and optimal algorithms for structural dynamicsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 5 2004X. Zhou Abstract The primary objectives of the present exposition are to: (i) provide a generalized unified mathematical framework and setting leading to the unique design of computational algorithms for structural dynamic problems encompassing the broad scope of linear multi-step (LMS) methods and within the limitation of the Dahlquist barrier theorem (Reference [3], G. Dahlquist, BIT 1963; 3: 27), and also leading to new designs of numerically dissipative methods with optimal algorithmic attributes that cannot be obtained employing existing frameworks in the literature, (ii) provide a meaningful characterization of various numerical dissipative/non-dissipative time integration algorithms both new and existing in the literature based on the overshoot behavior of algorithms leading to the notion of algorithms by design, (iii) provide design guidelines on selection of algorithms for structural dynamic analysis within the scope of LMS methods. For structural dynamics problems, first the so-called linear multi-step methods (LMS) are proven to be spectrally identical to a newly developed family of generalized single step single solve (GSSSS) algorithms. The design, synthesis and analysis of the unified framework of computational algorithms based on the overshooting behavior, and additional algorithmic properties such as second-order accuracy, and unconditional stability with numerical dissipative features yields three sub-classes of practical computational algorithms: (i) zero-order displacement and velocity overshoot (U0-V0) algorithms; (ii) zero-order displacement and first-order velocity overshoot (U0-V1) algorithms; and (iii) first-order displacement and zero-order velocity overshoot (U1-V0) algorithms (the remainder involving high-orders of overshooting behavior are not considered to be competitive from practical considerations). Within each sub-class of algorithms, further distinction is made between the design leading to optimal numerical dissipative and dispersive algorithms, the continuous acceleration algorithms and the discontinuous acceleration algorithms that are subsets, and correspond to the designed placement of the spurious root at the low-frequency limit or the high-frequency limit, respectively. The conclusion and design guidelines demonstrating that the U0-V1 algorithms are only suitable for given initial velocity problems, the U1-V0 algorithms are only suitable for given initial displacement problems, and the U0-V0 algorithms are ideal for either or both cases of given initial displacement and initial velocity problems are finally drawn. For the first time, the design leading to optimal algorithms in the context of a generalized single step single solve framework and within the limitation of the Dahlquist barrier that maintains second-order accuracy and unconditional stability with/without numerically dissipative features is described for structural dynamics computations; thereby, providing closure to the class of LMS methods. Copyright © 2003 John Wiley & Sons, Ltd. [source] Crystallographic Texture Development in Bismuth Sodium Titanate Prepared by Reactive-Templated Grain Growth MethodJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2004Toshio Kimura Bi0.5Na0.5TiO3 (BNT) and 0.94Bi0.5Na0.5TiO3·0.06BaTiO3 (BNT,BT) bulk ceramics with extensive ,100, texture were prepared by the reactive-templated grain growth method, using platelike Bi4Ti3O12 (BIT) particles as templates for BNT. Calcined compacts were composed of matrix grains with random orientation and ,100,-oriented grains transformed from aligned BIT particles, and the texture developed by the growth of oriented grains during sintering. Ceramics with extensive texture were obtained by using the starting mixture containing the maximum concentration of platelike BIT to form the maximum volume fraction of oriented grains. [source] Left conjugate gradient method for non-Hermitian linear systemsNUMERICAL LINEAR ALGEBRA WITH APPLICATIONS, Issue 10 2008Li-Ping Wang Abstract Recently, Yuan et al. (BIT: Numer. Math. 2004; 44(1):189,207) proposed the left conjugate gradient (LCG) method for real positive-definite linear systems. This paper aims to generalize their method for solving complex non-Hermitian linear systems. To avoid the breakdown that possibly occurred in the LCG method, we also propose the block left conjugate direction method and the block LCG (BLCG) method. It is found that no breakdown occurs in the BLCG method and the block idea also applies to the real nonsymmetric case. Numerical experiments demonstrate the usefulness of the proposed LCG method. Copyright © 2008 John Wiley & Sons, Ltd. [source] On RD-rational Krylov approximations to the core-functions of exponential integratorsNUMERICAL LINEAR ALGEBRA WITH APPLICATIONS, Issue 5 2007I. Moret Abstract The paper deals with the application of the restricted-denominator rational Krylov method, recently discussed in (BIT 2004; 44(3):595,615; SIAM J. Sci. Comput. 2005; 27:1438,1457), to the computation of the action of the so-called ,- functions, which play a fundamental role in several modern exponential integrators. The analysis here presented is devoted in particular to the construction of error estimates of easy practical use. Copyright © 2007 John Wiley & Sons, Ltd. [source] BIT/SHPS-1 Enhances Brain-Derived Neurotrophic Factor-Promoted Neuronal Survival in Cultured Cerebral Cortical NeuronsJOURNAL OF NEUROCHEMISTRY, Issue 4 2000Toshiyuki Araki Abstract: Brain-derived neurotrophic factor (BDNF) activates a variety of signaling molecules to exert various functions in the nervous system, including neuronal differentiation, survival, and regulation of synaptic plasticity. Previously, we have suggested that BIT/SHPS-1 (brain immunoglobulin-like molecule with tyrosine-based activation motifs/SHP substrate 1) is a substrate of Shp-2 and is involved in BDNF signaling in cultured cerebral cortical neurons. To elucidate the biological function of BIT/SHPS-1 in cultured cerebral cortical neurons in connection with its role in BDNF signaling, we generated recombinant adenovirus vectors expressing the wild type of rat BIT/SHPS-1 and its 4F mutant in which all tyrosine residues in the cytoplasmic domain of BIT/SHPS-1 were replaced with phenylalanine. Overexpression of wild-type BIT/SHPS-1, but not the 4F mutant, in cultured cerebral cortical neurons induced tyrosine phosphorylation of BIT/SHPS-1 itself and an association of Shp-2 with BIT/SHPS-1 even without addition of BDNF. We found that BDNF-promoted survival of cultured cerebral cortical neurons was enhanced by expression of the wild type and also 4F mutant, indicating that this enhancement by BIT/SHPS-1 does not depend on its tyrosine phosphorylation. BDNF-induced activation of mitogen-activated protein kinase was not altered by the expression of these proteins. In contrast, BDNF-induced activation of Akt was enhanced in neurons expressing wild-type or 4F mutant BIT/SHPS-1. In addition, LY294002, a specific inhibitor of phosphatidylinositol 3-kinase, blocked the enhancement of BDNF-promoted neuronal survival in both neurons expressing wild-type and 4F mutant BIT/SHPS-1. These results indicate that BIT/SHPS-1 contributes to BDNF-promoted survival of cultured cerebral cortical neurons, and that its effect depends on the phosphatidylinositol 3-kinase-Akt pathway. Our results suggest that a novel action of BIT/SHPS-1 does not occur through tyrosine phosphorylation of BIT/SHPS-1 in cultured cerebral cortical neurons. [source] Diversification Discount or Premium?THE JOURNAL OF FINANCE, Issue 2 2004New Evidence from the Business Information Tracking Series ABSTRACT I use the Business Information Tracking Series (BITS), a new census database that covers the whole U.S. economy at the establishment level, to examine whether the finding of a diversification discount is an artifact of segment data. BITS data allow me to construct business units that are more consistently and objectively defined than segments, and thus more comparable across firms. Using these data on a sample that yields a discount according to segment data, I find a diversification premium. The premium is robust to variations in the sample, business unit definition, and measures of excess value and diversification. [source] Intellectual Property Rights in Bilateral Investment Treaties and Access to Medicines: The Case of Latin AmericaTHE JOURNAL OF WORLD INTELLECTUAL PROPERTY, Issue 5 2006Rosa Castro Bernieri The link between intellectual property protection and access to medicines has been studied from different perspectives. After signing the Trade-Related Aspects of Intellectual Property Rights (TRIPS) Agreement, most developing and least developed countries agreed to protect pharmaceutical products under the patent system. Beyond the criticisms of this system as an incentive mechanism to encourage private investment in research and development, it is widely acknowledged that a balance must exist between its benefits and costs. The patent system interaction with public health policies is twofold: providing incentives to develop new medicines, on the one hand, and increasing the prices of medicines, on the other. The TRIPS Agreement, the Doha Declaration and the subsequent Decision on Implementation of Paragraph 6 of the Doha Declaration all recognized this important trade-off. Different effects prevail in each interest group or country and negotiations of international intellectual property right (IPR) standards reflect this conflict. Nevertheless, the post-TRIPS scenario is full of new bilateral and regional agreements. The old bilateral investment treaties (BITS) are evolving towards new forms of all-encompassing arrangements that include intellectual property and liberalization of trade and services, apart from the classical rules for investment protection. This trend imposes a new landscape in IPR protection: one in which the above-described balance might be inclining towards one side. This article analyzes some legal, political and economic features of this new generation of BITS in Latin America. [source] Self-Interest, Foreign Need, and Good Governance: Are Bilateral Investment Treaty Programs Similar to Aid Allocation?FOREIGN POLICY ANALYSIS, Issue 3 2006ERIC NEUMAYER Bilateral investment treaties (BITs) have become the most important legal mechanism for the encouragement and governance of foreign direct investment (FDI) in developing countries. Yet practically no systematic evidence exists on what motivates capital-exporting developed countries to sign BITs earlier with some developing countries than with others, if at all. The theoretical framework from the aid allocation literature suggests that developed countries pursue a mixture of self-interest, foreign need and, possibly, good governance. We find evidence that both economic interests of developed countries' foreign investors and political interests of developed countries determine their scheduling of BITs. However, foreign need as measured by per capita income is also a factor, whereas good governance by and large does not matter. These results suggest that BIT programs can be explained using the same framework successfully applied to the allocation of aid. At the same time, self-interest seems to be substantively more important than developing country need when it comes to BITs. [source] Delegating Differences: Bilateral Investment Treaties and Bargaining Over Dispute Resolution ProvisionsINTERNATIONAL STUDIES QUARTERLY, Issue 1 2010Todd Allee Bilateral investment treaties (BITs) have become the dominant source of rules on foreign direct investment (FDI), yet these treaties vary significantly in at least one important respect: whether they allow investment disputes to be settled through the International Centre for the Settlement of Investment Disputes (ICSID). Through the compilation and careful coding of the text of nearly 1,500 treaties, we identify systematic variation in "legal delegation" to ICSID across BITs and explain this important variation by drawing upon a bargaining framework. Home governments prefer and typically obtain ICSID clauses in their BITs, particularly when internal forces push strongly for such provisions and when they have significantly greater bargaining power than the other signatory. Yet some home governments are less likely to insist upon ICSID clauses if they have historical or military ties with the other government. On the other hand, although host governments are often hostile toward ICSID clauses, particularly when sovereignty costs are high, they are more likely to consent to such clauses when they are heavily constrained by their dependence on the global economy. Our findings have significant implications for those interested in FDI, legalization, international institutions, and interstate bargaining. [source] An evaluation of a supervised self-help programme for bulimic disordersCLINICAL PSYCHOLOGY AND PSYCHOTHERAPY (AN INTERNATIONAL JOURNAL OF THEORY & PRACTICE), Issue 4 2001Lorraine Bell Self-help programmes are recommended as cost-effective initial interventions for the treatment of bulimic disorders. This is a report of the effectiveness of such a programme in routine clinical practice. Twenty-one patients completed the programme and both pre- and post- measures. Patients were treated in a secondary mental health setting over an 11-month period from July 1998 to June 1999. Outcome was assessed using standardized measures and records of symptom levels and drop-out rates. Significant improvements in depression, bulimic symptom and severity were observed. Multi-impulsive clients (as indicated by clinically significant scores on bingeing and two other areas of impulsivity) had similar levels of bulimia but higher depression scores pre-treatment. They made significant gains in most areas but, despite reduction in depression scores, remained significantly depressed. They also made less improvement in disordered attitudes than non-impulsive clients. A global measure of motivation did not predict drop-out or outcome though numbers were small. Patients who used Getting Better Bit(e) by Bit(e) and received motivational enhancement sessions made a greater reduction in fasting behaviour and were less likely to drop out than those who used a more standard CBT programme, but these results could be due to other factors. Copyright © 2001 John Wiley & Sons, Ltd. [source] Two Bits: The Cultural Significance of Free Software by Christopher KeltyAMERICAN ANTHROPOLOGIST, Issue 4 2009DANIEL MILLER No abstract is available for this article. [source] Fiddling While the World BurnsARCHITECTURAL DESIGN, Issue 3 2010Neil Spiller Abstract Neil Spiller sharpens his claws and puts some bite into his final ,Bits' in this closing edition of AD+. He addresses the pressing question of climate change and politicians', architects' and the construction industry's general proclivity to bury their heads in the sand or to ,fiddle' tangentially in another direction. Copyright © 2010 John Wiley & Sons, Ltd. [source] Threatened obligatory riverine fishes in human-modified Polish riversECOLOGY OF FRESHWATER FISH, Issue 1-2 2000T. Penczak Abstract , The fate of obligatory riverine fish species (rheophils), which are the objects of anglers' exploitation (chub ,Leuciscus cephalus, nase ,Chondrostoma nasus, barbel ,Barbus barbus, gudgeon ,Gobio gobio), and brown trout (Salmo trutta m. fario) and grayling (Thymallus thymallus) (in the Gwda River basin only), were investigated in large alluvial rivers (Pilica and Warta) and in the medium-sized Gwda River basin. The Pilica (1973) and the Warta (1986,1987) were divided by large dams without fish ladders in their middle courses. The Gwda River was divided by only a few dams along its course, but its tributaries carrying pure water had numerous small dams that supplied water for fish farms. Other stresses influencing fish populations in these rivers were: pollution, overfishing, hydroelectric plants and bank revetments. Because the listed stresses occurred alternately and at various periods of time in these rivers, this enabled attributing the cause for extinction and reduction of the abundance and distribution. In the salmon Gwda River basin, a drastic decrease in spatial distribution and reduction of occurrence ranges of brown trout, grayling and barbel was evident in respect to the first study period (1980s) in the 1990s. In the large, alluvial Pilica River, nase, barbel and dace are on the edge of extinction and chub and gudgeon are vulnerable. In the Warta's tailwater, barbel is an extinct species, and chub, dace and gudgeon are vulnerable ones. In a site in the backwater, none of the above mentioned species became extinct, but their abundance and occurrence frequency decreased a bit in respect to the pre-impoundment period. Roach-generalist, which was used in this research as a "control" species, increased in abundance in all 3 rivers. These investigations univocally proved that the dams cause catastrophic stress for obligatory riverine species., [source] The international monetary system in the last and next 20 yearsECONOMIC POLICY, Issue 47 2006Barry Eichengreen SUMMARY The evolution of exchange rate regimes The last two decades have seen far-reaching changes in the structure of the international monetary system. Europe moved from the European Monetary System to the euro. China adopted a dollar peg and then moved to a basket, band and crawl in 2005. Emerging markets passed through a series of crises, leading some to adopt regimes of greater exchange rate flexibility and others to rethink the pace of capital account liberalization. Interpreting these developments is no easy task: some observers conclude that recent trends are confirmation of the ,bipolar view' that intermediate exchange rate arrangements are disappearing, while members of the ,fear of floating school' conclude precisely the opposite. We show that the two views can be reconciled if one distinguishes countries by their stage of economic and financial development. Among the advanced countries, intermediate regimes have essentially disappeared; this supports the bipolar view for the group of countries for which it was first developed. Within this subgroup, the dominant movement has been toward hard pegs, reflecting monetary unification in Europe. While emerging markets have also seen a decline in the prevalence of intermediate arrangements, these regimes still account for more than a third of the relevant subsample. Here the majority of the evacuees have moved to floats rather than fixes, reflecting the absence of EMU-like arrangements in other parts of the world. Among developing countries, the prevalence of intermediate regimes has again declined, but less dramatically. Where these regimes accounted for two-thirds of the developing country subsample in 1990, they account for a bit more than half of that subsample today. As with emerging markets, the majority of those abandoning the middle have moved to floats rather than hard pegs. The gradual nature of these trends does not suggest that intermediate regimes will disappear outside the advanced countries anytime soon. , Barry Eichengreen and Raul Razo-Garcia [source] An anatomical study of the rostral part of the equine oral cavity with respect to position and size of a snaffle bitEQUINE VETERINARY EDUCATION, Issue 3 2003E. Engelke First page of article [source] The effect of rising and sitting trot on back movements and head-neck position of the horseEQUINE VETERINARY JOURNAL, Issue 5 2009P. de COCQ Summary Reason for performing study: During trot, the rider can either rise from the saddle during every stride or remain seated. Rising trot is used frequently because it is widely assumed that it decreases the loading of the equine back. This has, however, not been demonstrated in an objective study. Objective: To determine the effects of rising and sitting trot on the movements of the horse. Hypothesis: Sitting trot has more extending effect on the horse's back than rising trot and also results in a higher head and neck position. Methods: Twelve horses and one rider were used. Kinematic data were captured at trot during over ground locomotion under 3 conditions: unloaded, rising trot and sitting trot. Back movements were calculated using a previously described method with a correction for trunk position. Head-neck position was expressed as extension and flexion of C1, C3 and C6, and vertical displacement of C1 and the bit. Results: Sitting trot had an overall extending effect on the back of horses when compared to the unloaded situation. In rising trot: the maximal flexion of the back was similar to the unloaded situation, while the maximal extension was similar to sitting trot; lateral bending of the back was larger than during the unloaded situation and sitting trot; and the horses held their heads lower than in the other conditions. The angle of C6 was more flexed in rising than in sitting trot. Conclusions and clinical relevance: The back movement during rising trot showed characteristics of both sitting trot and the unloaded condition. As the same maximal extension of the back is reached during rising and sitting trot, there is no reason to believe that rising trot was less challenging for the back. [source] The influence of head and neck position on kinematics of the back in riding horses at the walk and trotEQUINE VETERINARY JOURNAL, Issue 1 2005M. RHODIN Summary Reasons for performing study: A common opinion among riders and in the literature is that the positioning of the head and neck influences the back of the horse, but this has not yet been measured objectively. Objectives: To evaluate the effect of head and neck position on the kinematics of the back in riding horses. Methods: Eight Warmblood riding horses in regular work were studied on a treadmill at walk and trot with the head and neck in 3 different predetermined positions achieved by side reins attached to the bit and to an anticast roller. The 3-dimensional movement of the thoracolumbar spine was measured from the position of skin-fixed markers recorded by infrared videocameras. Results: Head and neck position influenced the movements of the back, especially at the walk. When the head was fixed in a high position at the walk, the flexion-extension movement and lateral bending of the lumbar back, as well as the axial rotation, were significantly reduced when compared to movements with the head free or in a low position. At walk, head and neck position also significantly influenced stride length, which was shortest with the head in a high position. At trot, the stride length was independent of head position. Conclusions: Restricting and restraining the position and movement of the head and neck alters the movement of the back and stride characteristics. With the head and neck in a high position stride length and flexion and extension of the caudal back were significantly reduced. Potential relevance: Use of side reins in training and rehabilitation programmes should be used with an understanding of the possible effects on the horse's back. [source] Concepts of neural nitric oxide-mediated transmissionEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2008John Garthwaite Abstract As a chemical transmitter in the mammalian central nervous system, nitric oxide (NO) is still thought a bit of an oddity, yet this role extends back to the beginnings of the evolution of the nervous system, predating many of the more familiar neurotransmitters. During the 20 years since it became known, evidence has accumulated for NO subserving an increasing number of functions in the mammalian central nervous system, as anticipated from the wide distribution of its synthetic and signal transduction machinery within it. This review attempts to probe beneath those functions and consider the cellular and molecular mechanisms through which NO evokes short- and long-term modifications in neural performance. With any transmitter, understanding its receptors is vital for decoding the language of communication. The receptor proteins specialised to detect NO are coupled to cGMP formation and provide an astonishing degree of amplification of even brief, low amplitude NO signals. Emphasis is given to the diverse ways in which NO receptor activation initiates changes in neuronal excitability and synaptic strength by acting at pre- and/or postsynaptic locations. Signalling to non-neuronal cells and an unexpected line of communication between endothelial cells and brain cells are also covered. Viewed from a mechanistic perspective, NO conforms to many of the rules governing more conventional neurotransmission, particularly of the metabotropic type, but stands out as being more economical and versatile, attributes that presumably account for its spectacular evolutionary success. [source] Performance analysis of a generic system model for uncoded IDMA using serial and parallel interference cancellation,EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 5 2008Oliver Nagy This paper shows how to accurately describe a fully synchronised interleave division multiple access (IDMA) scheme without channel coding by a matrix model. This model allows the derivation of the optimal detector and provides additional insights into the IDMA principle, and we show that the matrices are structured and sparse. We use BER and EXIT charts to study the performance of parallel and serial interference cancellation schemes and demonstrate that the latter converges faster and is independent of the scrambling code. Any bit interleaved DS-CDMA system can be viewed as a special case of IDMA, and an IDMA receiver can therefore be used to detect DS-CDMA signals. Copyright © 2008 John Wiley & Sons, Ltd. [source] The long-term average capacity region per unit cost with application to protocols for sensor networksEUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 1 2003Daniela Tuninetti We consider a wireless sensor network where K sensors must deliver their messages within a frame of N time slots by spending a given finite energy. If the messages are not transmitted within the required delay they become useless and the residual energy is wasted. The channel is block-fading, with independent fades for each sensor and each slot. Sensors know the fading levels up to the current slot, but do not know the future fading levels. The receiver collects the signal on all the slots of the frame and performs joint decoding of all the messages. We characterize the region of long-term average achievable rates and we show that the optimal policy tends to waterfilling in time (optimal policy without delay constraints) as N increases. In this setting, we also characterize the long-term average capacity region per unit energy by showing that the optimal policy is ,one-shot', totally decentralized and extremely simple, i.e., every user spends all its available energy on the first slot of the frame, the fading gain of which is larger than a pre-computed time-varying threshold. Furthermore, the ,one-shot' policy not only makes the most efficient use of the energy, but also reduces to the minimum the interference to other users as it makes all the users transmit with the minimum energy per bit required for reliable communications. These characteristics make the ,one-shot' policy appealing for systems with severe energy limitation as wireless sensor networks. Copyright © 2003 AEI [source] A field investigation of manual forces associated with trigger and push to start electric screwdriversHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 4 2007Brian D. Lowe This study investigated manual forces associated with trigger start (TS) and push to start (PTS) activation in-line electric screwdriver designs. The vertically directed axial screwdriver force transmitted with the driver to the fastener and the grip/finger forces on the driver handle were measured from 13 employees in an electronics assembly manufacturing facility. The PTS driver was associated with significantly ( p < .01) higher axial force than the TS driver at two of the four workstations, where the difference was as high as a 184% increase (36.5 vs. 103.8 N). Total finger force on the screwdriver handle was also higher for the PTS screwdriver ( p < .01). The PTS screwdriver may reduce instances of fastener head damage ("cam out") by requiring a minimum level of axial force to ensure better contact between the screwdriver bit and the fastener. However, this appears to come at the expense of greater manual forces exerted by the operator. © 2007 Wiley Periodicals, Inc. Hum Factors Man 17: 367,382, 2007. [source] Use of neural networks for the prediction of frictional drag and transmission of axial load in horizontal wellboresINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 2 2003Tanvir Sadiq Abstract The use of mud motors and other tools to accomplish forward motion of the bit in extended reach and horizontal wells allows avoiding large amounts of torque caused by rotation of the whole drill string. The forward motion of the drill string, however, is resisted by excessive amount of friction. In the presence of large compressive axial loads, the drill pipe or coiled tubing tends to buckle into a helix in horizontal boreholes. This causes additional frictional drag resisting the transmission of axial load (resulting from surface slack-off force) to the bit. As the magnitude of the frictional drag increases, a buckled pipe may become ,locked-up' making it almost impossible to drill further. In case of packers, the frictional drag may inhibit the transmission of set-up load to the packer. A prior knowledge of the magnitude of frictional drag for a given axial load and radial clearance can help avoid lock-up conditions and costly failure of the tubular. In this study a neural network model, for the prediction of frictional drag and axial load transmission in horizontal wellbores, is presented. Several neural network architectures were designed and tested to obtain the most accurate prediction. After cross-validation of the Back Propagation Neural Network (BPNN) algorithm, a two-hidden layer model was chosen for simultaneous prediction of frictional drag and axial load transmission. A comparison of results obtained from BPNN and General Regression Neural Network (GRNN) algorithms is also presented. Copyright © 2002 John Wiley & Sons, Ltd. [source] A bit of prose about poetryINTERNATIONAL JOURNAL OF APPLIED PSYCHOANALYTIC STUDIES, Issue 2 2008Salman Akhtar Abstract This brief communication delineates 10 outstanding characteristics of poetry. These include poetry's expression of preverbal experience, blending of primary and secondary processes, musical use of words, enhancement of mentalization, reduction of mental pain, cathexis of links and bonds, manifestation of culture, synthesis of neurophysiology, acceptance of the oedipal situation, and its location in the transitional realm. The paper then moves on to deconstruct the form of its message thus far and in the process sheds further light on the "work" of writing poetry. Copyright © 2008 John Wiley & Sons, Ltd. [source] Parallel combinatory multiple-subcarrier optical wireless communication systemsINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 3 2005Norio Kitamoto Abstract We analyse the performance of parallel combinatory multiple-subcarrier (PC-MS) optical wireless communication system. The PC-MS system can transmit more information at each symbol interval than conventional MS systems with the same subcarriers. In addition the PC-MS system can decrease the bias that must be added to the MS electrical signal, because the number of subcarriers other than null subcarriers is smaller than that in the conventional MS systems and thus the minimum power becomes larger. Therefore, the PC-MS system can decrease the required energy per bit. Copyright © 2005 John Wiley & Sons, Ltd. [source] PeckCryst: a program for structure determination from powder diffraction data using a particle swarm optimization algorithmJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 6 2009Zhen Jie Feng PeckCryst has been developed for the solution of molecular crystal structures from powder diffraction data using a particle swarm optimization (PSO) algorithm. In order to speed up the calculation process, a modified Bragg R factor is used as the evaluation function for the PSO algorithm. The effectiveness of the program has been tested by solving four known structures from powder diffraction data. A Python script is also provided for convenient repetitive running of PeckCryst. The distributed PeckCryst program is freely available from the authors upon request, and runs on Linux and Windows (32- and 64-bit) platforms. [source] Reciprocal-space imaging of a real quasicrystal.JOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2008A feasibility study with PILATUS 6M How many of the theoretically densely distributed Bragg reflections of a quasicrystal can be observed employing an area detector and synchrotron radiation? How does the reflection density of a real quasicrystal change as a function of exposure time, and what is the minimum distance between reflections? What does the distribution of diffuse scattering look like? To answer these questions, the Bragg reflection density of a perfect icosahedral quasicrystal with composition Al64Cu23Fe13 was measured employing a novel type of single-photon-counting X-ray pixel detector, PILATUS 6M, which allows noise-free data collection with the extraordinarily large dynamic range of 20,bit. The reflection density was found to be two orders of magnitude lower than expected for a strictly quasiperiodic structure. Moreover, diffuse scattering reflects significant structural disorder, breaking six-dimensional F -lattice symmetry. These findings have some implications for the interpretation of physical properties. [source] A Puzzle about Consent in Research and in PracticeJOURNAL OF APPLIED PHILOSOPHY, Issue 3 2010ERIC CHWANG abstract In this paper, I will examine a puzzling discrepancy between the way clinicians are allowed to treat their patients and the way researchers are allowed to treat their subjects: in certain cases, researchers are legally required to disclose quite a bit more information when obtaining consent from prospective subjects than clinicians are when obtaining consent from prospective patients. I will argue that the proper resolution of this puzzling discrepancy must appeal to a pragmatic criterion of disclosure for informed consent: that what needs to be disclosed in order for consent to be valid depends on what the patient/subject needs to know in order to make a decision. I will then use this pragmatic criterion of disclosure to argue that when obtaining consent researchers should be permitted to omit the same information clinicians are, given certain qualifications. I will also examine how this puzzle forces us to confront some perhaps surprising truths about valid consent. My broader aim in this paper is to examine, not so much the puzzle itself, but rather what this particular puzzle can teach us about more theoretical issues surrounding informed consent. [source] Life-threatening systemic toxicity and airway compromise from a common European adder bite to the tongueACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 10 2009L. C. G. HOEGBERG A 24-year-old man was bit on the tongue by a European common adder. Within 15 min following envenomation, he experienced tongue swelling, hypotension and impaired consciousness. Antihistamine, corticosteroid and crystalloids were administered. Within 105 min of envenomation, increasing oral, pharyngeal and facial oedema compromised the airway, leading to respiratory failure, concomitant with circulatory failure related to hypoxaemia and systemic toxic effects. Acute tracheotomy secured the airway, and two doses of antivenom successfully treated the systemic, toxic effects. The reaction was severe due to rapid and suspected high-dose uptake of venom, underlining the need for early advanced symptomatic treatment with airway control and early and eventually repeated dosing of antivenom. [source] Numerical instabilities in the computation of pseudopotential matrix elementsJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 2 2006Christoph van Wüllen Abstract Steep high angular momentum Gaussian basis functions in the vicinity of a nucleus whose inner electrons are replaced by an effective core potential may lead to numerical instabilities when calculating matrix elements of the core potential. Numerical roundoff errors may be amplified to an extent that spoils any result obtained in such a calculation. Effective core potential matrix elements for a model problem are computed with high numerical accuracy using the standard algorithm used in quantum chemical codes and compared to results of the MOLPRO program. Thus, it is demonstrated how the relative and absolute errors depend an basis function angular momenta, basis function exponents and the distance between the off-center basis function and the center carrying the effective core potential. Then, the problem is analyzed and closed expressions are derived for the expected numerical error in the limit of large basis function exponents. It is briefly discussed how other algorithms would behave in the critical case, and they are found to have problems as well. The numerical stability could be increased a little bit if the type 1 matrix elements were computed without making use of a partial wave expansion. © 2005 Wiley Periodicals, Inc., J Comput Chem 27: 135,141 2006 [source] Quantum bits with polyacetyleneJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 9 2002Andre Elvas Pereira Da Silva Abstract The dynamics of a polyacetylene single chain as a system for possible physical implementations of quantum bits is determined. This novel proposition is studied by varying intensity and duration of application of an electric field as well as the intensity, number, and position in the polymer chain of impurity molecules. The behavior of soliton pairs, whose associated energy levels form the quantum bit, is analyzed. The chain is modeled by a modified Pariser,Parr,Pople Hamiltonian extended to include the effects of an external electric field and the parameters of the impurity molecules. The effect of the variation of the field and impurities on the separation of the energy levels associated with soliton pairs is analyzed by numerical integration of the equations of motion. Two different approaches for controlling the separation of levels are presented, and their features compared. First, the use of changes in the electric field to control the distance (and ultimately coupling) between two solitons moving freely on the chain or captured by the potential generated by the impurity molecules. Second, the change in the intensity of the impurities alone, with no application of an external field. We have found that the effect of the use of the field on the separation of levels is much smaller than the one obtained by changes in the parameters of the impurity molecules, which eventually led us to achieve quantum bit behavior in a polyacetylene chain. The influence of the field and impurity parameters in the energy levels is determined, as well as their role in the coupling of the two solitons on the chain. Critical values for distance between solitons, intensity of field, and impurities that determine whether a pair of solitons can work as a quantum bit are obtained. © 2002 Wiley Periodicals, Inc. J Comput Chem 9: 870,873, 2002 [source] | ||||||||||||||||||||||||||||||||||||||||