bluuebunny/crossref_metadata_2025 huggingface dataset:
Evolving Fisher Kernels for Biological Sequence Classification
Authors: Won K.-J. , Saunders C. , Prügel-Bennett A.
Published: December 2011

Fisher kernels have been successfully applied to many problems in bioinformatics. However, their success depends on the quality of the generative model upon which they are built. For Fisher kernel techniques to be used on novel problems, a mechanism for creating accurate generative models is required. A novel framework is presented for automatically creating domain-specific generative models that can be used to produce Fisher kernels for support vector machines (SVMs) and other kernel methods. The framework enables the capture of prior knowledge and addresses the issue of domain-specific kernels, both of which are current areas that are lacking in many kernel-based methods. To obtain the generative model, genetic algorithms are used to evolve the structure of hidden Markov models (HMMs). A Fisher kernel is subsequently created from the HMM, and used in conjunction with an SVM, to improve the discriminative power. This paper investigates the effectiveness of the proposed method, named GA-SVM. We show that its performance is comparable if not better than other state of the art methods in classifying secretory protein sequences of malaria. More interestingly, it showed better results than the sequence-similarity-based approach, without the need for additional homologous sequence information in protein enzyme family classification. The experiments clearly demonstrate that the GA-SVM is a novel way to find features with good performance from biological sequences, that does not require extensive tuning of a complex model.
Within-Culture Variations of Collectivism in Japan
Authors: Yamawaki Niwako
Published: December 2011

Modeling after Vandello and Cohen’s American Collectivism Index, the researcher developed a scale to measure collectivism in prefectures (similar to U.S. states) in Japan. The new scale was evaluated against results from the Japanese General Social Survey, a national survey of individuals conducted annually, and was tested for association with common correlates of cultural syndromes. As expected, the Japanese Collectivism Scale (JCS) was reliable and was significantly associated with results of the individual-level attitudinal survey and the correlates of collectivism. The JCS also showed within-culture variations of collectivism in Japan—variations that are important to consider when interpreting cross-cultural differences in attitudes and behavior.
The Relationship Between Perceived Parental Rejection and Adjustment for Arab, Canadian, and Arab Canadian Youth
Authors: Rasmi Sarah , Chuang Susan S. , Safdar Saba
Published: December 2011

The present study examined whether psychological well-being, life satisfaction, and risk behavior differed among European Canadian ( n = 147), Arab Canadian ( n = 129), and Arab youth in Egypt and Lebanon ( n = 131). Using parental acceptance-rejection theory, we also examined the strength of associations between perceived parental rejection and positive and negative outcomes for these youth. Our results suggested that European Canadian youth were less likely to perceive parental rejection and had higher life satisfaction than both Arab groups. However, although Arab Canadians and Arabs perceived more parental rejection than their European Canadian counterparts, it had less of an effect on their adjustment. We argued that culturally normative aspects of parent-youth relationships in Arab families may mitigate the effects of perceived parental rejection and that immigration may not exert a negative effect on Arab families in Canada. Instead, we suggested that researchers need to focus on the strengths of youth and families, rather than the negative effects of immigration and/or cultural group status.
Self-Enhancement and Self-Protection Strategies in China
Authors: Hepper Erica G. , Sedikides Constantine , Cai Huajian
Published: December 2011

The motive to enhance and protect positive views of the self manifests in a variety of cognitive and behavioral strategies, but its universality versus cultural specificity is debated by scholars. We sought to inform this debate by soliciting self-reports of the four principal types of self-enhancement and self-protection strategy (positivity embracement, favorable construals, self-affirming reflections, defensiveness) from a Chinese sample and comparing their structure, levels, and correlates to a Western sample. The Chinese data fit the same factor structure and were subject to the same individual differences in regulatory focus, self-esteem, and narcissism, as the Western data. Chinese participants reported lower levels of (enhancement-oriented) positivity embracement but higher levels of (protection-oriented) defensiveness than Western participants. Levels of favorable construals were also higher in the Chinese sample, with no differences in self-affirming reflections. These findings support and extend the universalist perspective on the self by demonstrating the cross-cultural structure, yet culturally sensitive manifestation, of self-enhancement motivation.
Perceiving One’s Own and Others’ Feelings Around the World
Authors: Lischetzke Tanja , Eid Michael , Diener Ed
Published: December 2011

The present study examined meta-mood variables pertaining to beliefs about the perception of one’s own and other people’s feelings across nations. A total of 9,102 college students from 42 nations provided self-reports of attention to and clarity of their own feelings, attention to and clarity of others’ feelings, and the cognitive (life satisfaction) and the affective (affect balance) component of subjective well-being (SWB). Multilevel analyses tested whether nations differed in the relations between meta-mood variables and SWB and whether the cultural dimension of individualism-collectivism moderated these relations. Attention to own feelings demonstrated a heterogeneous relation with SWB across nations. Clarity of own feelings showed an adaptive pattern in nearly all nations, but it was more closely related to SWB in individualistic than in collectivistic nations. Attention to others’ feelings demonstrated low positive relations with SWB in most nations. Unexpectedly, clarity of others’ feelings tended to be less important to affect balance in collectivistic than in individualistic nations. The results suggest that although beliefs about clearly perceiving own and others’ feelings might, to some degree, be universally adaptive, cultural differences appear to exist in how relevant the perception of feelings is to SWB.
Culture Moderates the Pliability of Ambivalent Attitudes
Authors: Ng Andy H. , Hynie Michaela , MacDonald Tara K.
Published: December 2011

Ambivalent attitudes are comprised of conflicting components. In response to this evaluative conflict, North Americans are more likely to change high ambivalent attitudes than low ambivalent attitudes. However, East Asians exhibit greater tolerance for inconsistencies than do North Americans. Hence, we hypothesized that culture would interact with ambivalence in influencing the degree of attitude change in response to a persuasive attempt. Results indicated that culture significantly moderated the relationship between ambivalence and attitude pliability, such that ambivalence and the degree of attitude change were positively associated for European Canadians but not for East Asian Canadians. These results add to the extant literature on attitudinal ambivalence, demonstrating cultural variability in the pliability of ambivalent attitudes.
Current and Historical Antecedents of Individual Value Differences Across 195 Regions in Europe
Authors: van Herk Hester , Poortinga Ype H.
Published: December 2011

This study analyzes differences on two value dimensions, conservation and self-enhancement, at both the individual and regional level across Europe. Within-country regions represent “cultunits” that often have belonged to different nation-states in history. Eight antecedent variables are explored. At the regional level, the variables include historical sociopolitical context, recent sociopolitical context, regional affluence, and main religion of the region; at the individual level, they feature religiousness, education, gender, and age cohort. The largest effects for region are associated with Gross Domestic Product, including differences between former Communist and non-Communist regions. Hardly any effects pertain to more distant history. At the individual level, there are substantial differences across age cohorts and effects of education, religiosity, and gender. Interactions between region- and individual-level conditions suggest people’s values are shaped in their youth; the largest differences mark cohorts in Central and Western Europe who were raised during the Cold War.
The Impact of Carbon Emission Reducing Design Features on Office Occupiers’ Choice of Premises
Authors: Leishman Chris , Orr Allison , Pellegrini-Masini Giuseppe
Published: December 2011

Energy saving measures, if incorporated into existing and new buildings, can help the UK to achieve its ambitious goal to reduce carbon emissions by 80 per cent by 2050. Yet, the penetration of such technologies has been slow in the commercial real estate market. This paper examines the attitudes and preferences of office end users and their acceptance of carbon emission reducing technologies. It employs conjoint analysis to model the real estate decision-making of 150 respondents who claimed to have an input into their organisation’s choice of premises. The findings demonstrate that functionality and accessibility remain top priorities in occupiers’ choice of premises. Lower rents, improved corporate image and productivity are revealed as attributes that could compensate occupiers for energy-efficient attributes that restrict control over internal environment and operation of equipment. The paper discusses instruments to promote greater acceptance and penetration of carbon emission reducing design features in the office market.
University Students Sharing Flats: When Studentification Becomes Vertical
Authors: Garmendia Maddi , Coronado José M. , Ureña José M.
Published: December 2011

This paper presents a study about studentification in a small, compact Spanish city. Unlike most of the previously analysed cases, students of this city share flats instead of living in houses in multiple occupancy. The studentification, which is hardly perceptible in the streets or the neighbourhood, becomes a reality in the staircase community, giving rise to the term ‘vertical studentification’. A survey was conducted amongst university students to locate and quantify the floating population of students. Also, long-term residents and landlords were interviewed to assess the impact of students on the communities of apartment blocks. The study reveals that studentification does happen in a high-rise morphology but in a vertical and hidden way, making policy implications less straightforward.
Politics and morality in Habermas’ discourse ethics
Authors: Khan Gulshan
Published: December 2011

In this article I argue that Jürgen Habermas’ notion of morality (moral norms) has more in common with Hegel’s notion of ‘ethical life’ as a ‘ sittlich’ relation – understood as a socially integrative force – rather than Kant’s supreme principle of personal morality. I show that Habermas and Hegel, each in his own way, make a distinction between morality and ethics. However, I make the case that Habermas’ conception of ‘morality’ incorporates aspects of Hegel’s notion of ‘ethical life’, while Habermas’ conception of ‘ethical’ – referring to individual and group conceptions of the good life – is a remedy to the shortcomings in Hegel’s overly unified ethical life. I offer an alternative reading of Habermas’ principle of morality, which I suggest should be read as his attempt to provide a binding process to set up the norms that ought to condition a modern political community understood as a civil association.
MacIntyre’s Nietzsche or Nietzschean MacIntyre?
Authors: Korkut Buket
Published: December 2011

In After Virtue, Alasdair MacIntyre argues that the Enlightenment project of providing grounds for morality has been a failure, and believes that as a result, we are left with one of the two options: either a revival of Aristotelian virtue ethics or an endorsement of Nietzschean emotivism, i.e. a version of moral relativism. I shall first challenge MacIntyre’s emotivist portrait of Nietzsche and suggest an alternative reading of Nietzsche. If my diagnosis is correct, then we also need to reinterpret the relation between MacIntyre and Nietzsche. This article aims to identify the difference in their characterization of the problem of morality, evaluate their proposal for a possible dissolution of the problem, and compare their method of moral enquiry.
Perspectives and ideologies: A pragmatic use for recognition theory
Authors: Decker Kevin S.
Published: December 2011

‘Recognition’ is a normative concept denoting the ascription of positive status to a group or an individual by (an) other(s). In its larger meaning, it carries the implication that when a group or an individual can justifiably expect such a positive status-ascription, its denial (misrecognition) is unjustified and unethical. I discuss the role that the concept of recognition can play at the intersection of two philosophies, pragmatism and contemporary critical theory. My perspective is one that embraces the ‘pragmatic turn’ in critical theory and sees the possibility of reciprocal benefit for pragmatism in how critical theory handles issues of material culture, alienation and networks of power. I argue that a critical social theory incorporating pragmatist presuppositions ought to bring the concept of recognition to bear in how it isolates and treats the ‘real interests’ of groups and individuals who have suffered and continue to suffer from broad social ascriptions of negative status, or who, through lack of voice and access to the public sphere, remain paralysed to participation in a thriving liberal democracy. In doing so, I do not construe recognition primarily as ‘positive tolerance’ or understanding of cultural, ethnic, or gender identity, but as a minimally substantive tool for understanding, and potentially correcting, how misrecognition impacts the collective and individual agency of the historically oppressed.
‘My future doesn’t know ME’: Time and subjectivity in poetry by young people
Authors: Conrad Rachel
Published: December 2011

This article explores children’s imaginative representations of time in relation to self-experience. Poems published in a young poets’ anthology edited by Naomi Shihab Nye are analyzed in order to discern models of temporality and subjectivity imagined by young writers. A dynamic temporality is seen in a subset of poems which manipulate time through crossing temporal references, expanding time frames, or claiming power over time. The article argues that poetry written by young people is a valuable lens on their subjectivity and temporality, and concludes by suggesting the value of incorporating arts and humanities approaches in social inquiry concerning childhood.
Effect of the electrode particle shape in Li-ion battery on the mechanical degradation during charge–discharge cycling
Authors: Vanimisetti Sampath K , Ramakrishnan Narayanrao
Published: December 2011

The investigation addresses the effect of shape and aspect ratio, of typical electrode particles of Li-ion cell material, on the extent of fracture surface created due to intercalation-induced strain energy. Nodular, fibrous, and flaky-shaped particles were studied approximating them to sphere, cylinder, and disc geometries, respectively. Analytical expressions for stress distribution in slab and cylindrical-shaped particles were derived using thermal stress analogy. Such results are already available for spherical particles. Finite element study was carried out using COMSOL® Multiphysics package to complement the analytical work as well as for verification. The spatial and temporal variations of stresses and strain energy in the electrode particles of different shapes were established. Reportedly, solid electrolyte interphase formed on the fracture surface as well as the fracture-induced isolation of electrode material are the main causes of performance degradation and in this context, the intercalation-induced strain energy density becomes important. The sphericity of a particle, that is, the ratio of the surface area of a sphere to that of the particle of equal volume, was found to fittingly describe the effect of shape. The average strain energy density stored in a particle increases with the increasing sphericity. Therefore, fibrous and flaky-shaped particles are expected to have lower tendency for mechanical degradation than the nodular ones. The analysis is restricted only to the mechanics of mechanical degradation and not to the process or the chemistry point of view.
Holocene climate variability and environmental history at the Patagonian forest/steppe ecotone: Lago Mosquito (42°29'37.89''S, 71°24'14.57''W) and Laguna del Cóndor (42°20'47.22''S, 71°17'07.62''W)
Authors: Iglesias Virginia , Whitlock Cathy , Bianchi M Martha , Villarosa Gustavo , Outes Valeria
Published: December 2011

Along the eastern Andes, a sharp ecotone separates steppe from North Patagonian forest dominated by Nothofagus spp. and Austrocedrus chilensis. The longitudinal position of the ecotone is largely determined by effective moisture, which in turn is partly governed by the strength and latitudinal position of the Southern Westerlies. As a result, changes in the ecotone provide an opportunity to examine past climate variations. Holocene environmental history at two sites in close proximity is inferred from pollen and high-resolution charcoal data. Prior to 9000 cal. yr BP, vegetation resembled a steppe, in accordance with widespread aridity. Fires were infrequent, likely as a consequence of fuel discontinuity associated with low vegetation cover. At 9000 cal. yr BP, forest taxa expanded into steppe and fires became frequent, indicating that summers were arid enough to support fires but winter moisture was sufficient for Nothofagus spp. to expand. A two-step increase in effective moisture is inferred for the middle Holocene. The first step occurred at 8500 cal. yr BP, as interpreted from the increase in A. chilensis in the region, probably as a consequence of an eastward migration from glacial refugia. The second step at 5500 cal. yr BP is based on a Nothofagus spp. expansion into the steppe. Steppe readvances into the forest between 5250 and 3000 cal. yr BP indicate decreased temperatures and/or effective moisture. The last 3000 years are characterized by expansions of A. chilensis and an eastward shift of the ecotone, suggesting more humid conditions. European settlement is reflected in the establishment of non-native species and disturbance-adapted taxa.
Southern Hemisphere high-resolution palaeoclimate records of the last 2000 years
Authors: Neukom Raphael , Gergis Joëlle
Published: December 2011

This study presents a comprehensive assessment of high-resolution Southern Hemisphere (SH) paleoarchives covering the last 2000 years. We identified 174 monthly to annually resolved climate proxy (tree ring, coral, ice core, documentary, speleothem and sedimentary) records from the Hemisphere. We assess the interannual and decadal sensitivity of each proxy record to large-scale circulation indices from the Pacific, Indian and Southern Ocean regions over the twentieth century. We then analyse the potential of this newly expanded palaeoclimate network to collectively represent predictands (sea surface temperature, sea level pressure, surface air temperature and precipitation) commonly used in climate reconstructions. The key dynamical centres-of-action of the equatorial Indo-Pacific are well captured by the palaeoclimate network, indicating that there is considerable reconstruction potential in this region, particularly in the post AD 1600 period when a number of long coral records are available. Current spatiotemporal gaps in data coverage and regions where significant potential for future proxy collection exists are discussed. We then highlight the need for new and extended records from key dynamical regions of the Southern Hemisphere. Although large-scale climate field reconstructions for the SH are in their infancy, we report that excellent progress in the development of regional proxies now makes plausible estimates of continental- to hemispheric-scale climate variations possible.
Vertical modelling: Analysis of competing risks data with missing causes of failure
Authors: Nicolaie MA , van Houwelingen HC , Putter H
Published: December 2011

We propose vertical modelling as a natural approach to the problem of analysis of competing risks data when failure types are missing for some individuals. Under a natural missing-at-random assumption for these missing failure types, we use the observed data likelihood to estimate its parameters and show that the all-cause hazard and the relative hazards appearing in vertical modelling are indeed key quantities of this likelihood. This fact has practical implications in that it suggests vertical modelling as a simple and attractive method of analysis in competing risks with missing causes of failure; all individuals are used in estimating the all-cause hazard and only those with non-missing cause of failure for relative hazards. The relative hazards also appear in a multiple imputation approach to the same problem proposed by Lu and Tsiatis and in the EM algorithm. We compare the vertical modelling approach with the method of Goetghebeur and Ryan for a breast cancer data set, highlighting the different aspects they contribute to the data analysis.
The choice of test in phase II cancer trials assessing continuous tumour shrinkage when complete responses are expected
Authors: Wason James MS , Mander Adrian P
Published: December 2011

Traditionally, phase II cancer trials test a binary endpoint formed from a dichotomisation of the continuous change in tumour size. Directly testing the continuous endpoint provides considerable gains in power, although also results in several statistical issues. One such issue is when complete responses, i.e. complete tumour removal, are observed in multiple patients; this is a problem when normality is assumed. Using simulated data and a recently published phase II trial, we investigate how the choice of test affects the operating characteristics of the trial. We propose using parametric tests based on the censored normal distribution, comparing them to the t-test and Wilcoxon non-parametric test. The censored normal distribution fits the real dataset well, but simulations indicate its type-I error rate is inflated, and its power is only slightly higher than the t-test. The Wilcoxon test has deflated type I error. For two-arm designs, the differences are much smaller. We conclude that the t-test is suitable for use when complete responses are present, although positively skewed data can result in the non-parametric test having higher power.
Public Meeting Facilitation
Authors: Beck Stephenson J. , Littlefield Robert S. , Weber Andrea J.
Published: December 2011

During the record 2009 flood, the city of Fargo, North Dakota, United States held daily televised public meetings. Unknown to many citizens, the city also held private premeetings to prepare for the public meetings. The present study examined city leaders’ naïve theories of meeting facilitation in light of a minimalist view of public meetings ( McComas, 2001 ). Interviews of city leaders during and after the flood, as well as meeting transcripts, were analyzed. Findings indicated that city leaders believed debate about controversial issues should be contained within private premeetings, where leaders planned how to be open with citizens during public meetings. City leaders also believed public meetings had to portray a calm yet urgent image for the public. City leaders used micro-level (e.g., humor, explicit vigilant messages, and metaphor) and macro-level (transparency) processes to communicatively accomplish their desires.
Correlation Between Retroperitoneal Lymph Node Size and Presence of Metastases in Nonseminomatous Germ Cell Tumors
Authors: Hudolin Tvrtko , Kastelan Zeljko , Knezevic Nikola , Goluza Eleonora , Tomas Davor , Coric Marijana
Published: December 2011

Eighty-five patients had staging laparoscopic retroperitoneal lymph node dissection (L-RPLND) for nonseminomatous germ cell tumors at our institution. The largest lymph node size was measured and presence or absence of metastatic disease was determined. A total of 1139 lymph nodes have been removed and in 27 (31.8%) patients, metastases in one or more lymph nodes were detected. There were 338 (29.7%) hilar, 259 (22.7%) paraaortic, 221 (19.4%) interaortocaval, 171 (15%) paracaval, 133 (11.7%) preaortic and 17 (1.5%) precaval lymph nodes. The total number of lymph nodes with metastases was 74 (6.5%), and 1065 (93.5%) nodes did not have any metastases. The average size of a lymph node with metastases was 1.05 (0.3-3), and without metastases it was 0.55 (0.1-2.5) cm, (p<0.001). If we use > 1 cm size of a lymph node as a “cut-off” value for enlargement and presence of metastases, 60% of metastatic lymph nodes would be missed since they were all ≤ 1 cm. Our results have shown that decreasing size of lymph nodes which are considered positive from > 1 cm to 0.7 -0.8 cm can be recommended, with specificity and sensitivity equal 70%.
Plasma Cell Granuloma of the Thyroid Gland
Authors: Cremonini Anna , Ponzoni Maurilio , Beretta Edoardo , Mari Gilberto , Cangi Maria Giulia , Arrigoni Gianluigi , Doglioni Claudio
Published: December 2011

This study reports a case of plasma cell granuloma of the thyroid gland in a 47-year-old woman, presenting with a right subhyoid mass and a previous diagnosis of Hashimoto thyroiditis dating back to 1988, which was made on a subtotal thyroidectomy. Plasma cell granuloma preferentially involves the lung, with only 18 cases of thyroid gland involvement having been reported to date in the English literature. Thyroid plasma cell granuloma preferentially affects women and classically shows a prominent plasma cell infiltrate embedded in a variable degree of fibrous stroma: only 2 of the reported cases exhibited the morphologic features of inflammatory myofibroblastic tumor. These morphologic features may raise problems in the differential diagnosis with other plasma cell–rich disorders, including infectious diseases and auto(dys)immune conditions, including the recently described “IgG4-related sclerosing disease.” In view of these considerations, a contemporary diagnostic approach to thyroid plasma cell granuloma is therefore discussed here.
Primary Malignant Teratoma of Lung
Authors: Giunchi Francesca , Segura Juan José
Published: December 2011

We describe a rare case of malignant teratoma involving the entire right lung. A 28 years old man was admitted to the hospital with severe respiratory failure and general malaise. Chest X-ray showed a dense opacity of the entire right lung, accompanied by pleural effusion. At autopsy, the right lung was completed replaced by a mass of variegated appearance combining cystic spaces and solid areas. Microscopically, the lung tumor exhibited a polymorphous histological picture. Most of the tissue had a malignant mesenchymal appearance, which included areas of chondrosarcoma, chondroblastic osteosarcoma, well differentiated liposarcoma, and undifferentiated pleomorphic sarcoma. Other areas of the tumor showed malignant epithelial components consistent with bronchial and urothelial mucosa with also scattered islands of pigmented epithelium of probable neuronal or retinal nature.
Application of a near-field acoustic holography-based diagnosis technique in gearbox fault diagnosis
Authors: Hou Junjian , Jiang Weikang , Lu Wenbo
Published: December 2011

With the combination of the near-field acoustic holography (NAH) and pattern recognition technique, a NAH-based diagnosis technique is proposed and applied to diagnose gearbox faults by analyzing the sound field distribution information first. After visualizing the sound fields under different working conditions by NAH, the spatial gray level co-occurrence matrices based textural features can be obtained from the NAH images. Then, the support vector machine is employed to identify different working conditions and diagnose the faults. Two gearbox experiments with different gear faults and fault severity are studied in a semi-anechoic chamber to verify the NAH-based diagnosis technique. The experimental results demonstrate that the NAH-based diagnosis method is feasible and effective, and can be anticipated as a choice for gearbox fault diagnosis.
Hybrid under-actuated control for autonomous dynamic balance of a running electrical bicycle including motor dynamics and in the presence of huge uncertainty
Authors: Hwang Chih-Lyang , Wu Hsiu-Ming , Shih Ching-Long
Published: December 2011

Hybrid under-actuated control for the autonomous dynamic balance of a running electrical bicycle including frictional torque and motor dynamics is developed, which includes two control inputs: steering and pendulum voltages, and three system outputs: steering, lean and pendulum angles. Due to the under-actuated feature, two novel reference signals using three system outputs are designed so that the number of control inputs and sliding surfaces is the same. According to the input-output data of each subsystem, two scaling factors for each subsystem are first employed to normalize the sliding surface and its derivative. Based on the concept of if-then rule, an appropriate rule table for the ith subsystem is obtained. The output scaling factor based on Lyapunov stability is also determined. It is called fuzzy decentralized sliding mode under-actuated control (FDSMUC). Because the uncertainties of a running electrical bicycle system, caused by different ground conditions, gusts of wind, and interactions among subsystems, are often huge, an extra compensation of learning uncertainty is plunged into FDSMUC to enhance the system performance. We call it fuzzy decentralized sliding mode adaptive under-actuated control (FDSMAUC). To avoid the unnecessary transience caused by uncertainties and preserve the dynamic balance, the combination of FDSMUC and FDSMAUC with a transition (i.e., Hybrid FDSMUC) is suggested. The stability of the closed-loop system using the proposed control is verified by Lyapunov stability theorem. Finally, the compared simulations validate the efficiency among the FDSMUC, FDSMAUC and Hybrid FDSMUC.
Active vibration control of conical shells using piezoelectric materials
Authors: Li Feng-Ming , Song Zhi-Guang , Chen Zhao-Bo
Published: December 2011

In this paper, the active vibration control of conical shells is studied using velocity feedback and linear quadratic regulator methods. Up to now, many researches on the active vibration control of beams, plates and cylindrical shells have been published, however, to our knowledge, few people have studied the active vibration control of conical shells. Normally, in the equation of motion of the conical shells, some coefficients are variables, which makes the equation of motion of the conical shells very complicated and difficult to solve analytically. In order to solve this problem, Hamilton’s principle with the assumed mode method is employed to derive the equation of motion of the complex electromechanical coupling system. This equation of motion for the conical shell and piezoelectric patch system can be easily solved and effectively used for the structural active vibration control. Based on the traditional theory of structural dynamics, this method is easy to understand and is verified by numerical simulations. The forced vibration responses of the conical shells with two piezoelectric patches are computed to study the active vibration control. The optimal design for the locations of the piezoelectric patches is also developed by the genetic algorithm. From the results it can be seen that the control gain has a significant effect on the vibration control of the conical shell, but the effect of the size of the piezoelectric patches on controlling the vibration amplitudes is not so obvious. The overall vibration of the conical shell can be effectively reduced by the velocity feedback control method. With the increase of the control gain, the active damping characteristics of the conical shell are improved. Moreover, the optimal placement scheme of the piezoelectric patches obtained by the genetic algorithm can significantly reduce the vibration amplitudes of the conical shell.
A study on the application of hedge algebras to active fuzzy control of a seism-excited structure
Authors: Duc Nguyen Dinh , Vu Nhu-Lan , Tran Duc-Trung , Bui Hai-Le
Published: December 2011

The active control problem of seism-excited civil structures has attracted considerable attention in recent years. In this paper, conventional, hedge-algebras-based and optimal hedge-algebras-based fuzzy controllers, respectively denoted by HAFCs and OHAFCs, are designed to suppress vibrations of a structure against earthquake. The interested structure is a building modeled as a four-degrees-of-freedom structure system with one actuator, which is an active tendon, installed on the first floor. The structural system is simulated against the ground motion, acting on the base, of the El Centro earthquake ( Mw = 7.1) in the USA on 18 May 1940. The control effects of FC, HAFC and OHAFC are compared via the time history of the floor displacements and velocities, control error and control force of the structure.
Numerical investigation on smart magnetically controlled elastomeric bearings
Authors: Vidrih Zlatko , Fischinger Matej , Isaković Tatjana
Published: December 2011

The stiffness of rubber bearings, which are widely used for the seismic isolation of different types of structures, changes under different seismic intensities. These bearings are typically designed considering only lateral displacements induced by design earthquakes. At lower displacements, induced by weaker earthquakes, the stiffness of rubber bearings is typically increased, and the efficiency of the seismic isolation is thus reduced. To improve the response of rubber isolators at lower seismic intensities, a new isolation device, which can adjust itself to the intensity of the load, has been developed. It is fabricated from a magnetically controlled elastomer (MCE), whose stiffness can be varied by applying a magnetic field. Variation of the device stiffness is regulated by a specifically designed control unit. The seismic response of this new device was tested experimentally and analytically. This study showed that the new device can substantially reduce the seismic demand, particularly in the case of fairly stiff structures, and the equipment installed in such structures. It was found that the group of equipment, which is critical in the case of weak earthquakes, can be substantially reduced or even completely eliminated when stiff structures are isolated using MCE devices.
Boundary control of a rotating shear beam with observer feedback
Authors: Dog̃an Mustafa , Morgül Ömer
Published: December 2011

We consider a flexible structure modeled as a shear beam which is free to rotate on the horizontal plane. We first model the system by using partial differential equations and we propose boundary feedback laws to achieve set-point regulation of the rotation angle as well as to suppress elastic vibrations. The main advantage of the proposed design, which consists of a decoupling controller together with an observer, is that it is easy to implement. We utilize a coordinate transformation based on an invertible integral transformation by using Volterra form and backstepping techniques. We show that with the proposed controller, the control objectives are satisfied.
Complex-order forced van der Pol oscillator
Authors: Pinto Carla MA , Machado JA Tenreiro
Published: December 2011

In this paper we consider a complex-order forced van der Pol oscillator. The complex derivative [Formula: see text], with α, β ∈ ℝ+, is a generalization of the concept of an integer derivative, where α = 1, β = 0. The Fourier transforms of the periodic solutions of the complex-order forced van der Pol oscillator are computed for various values of parameters such as frequency ω and amplitude b of the external forcing, the damping μ, and parameters α and β. Moreover, we consider two cases: (i) b = 1, μ = {1.0, 5.0, 10.0}, and ω = {0.5, 2.46, 5.0, 20.0}; (ii) ω = 20.0, μ = {1.0, 5.0, 10.0}, and b = {1.0, 5.0, 10.0}. We verified that most of the signal energy is concentrated in the fundamental harmonic ω0. We also observed that the fundamental frequency of the oscillations ω0 varies with α and μ. For the range of tested values, the numerical fitting led to logarithmic approximations for system (7) in the two cases (i) and (ii). In conclusion, we verify that by varying the parameter values α and β of the complex-order derivative in expression (7), we accomplished a very effective way of perturbing the dynamical behavior of the forced van der Pol oscillator, which is no longer limited to parameters b and ω.
Acceleration harmonic identification for an electro-hydraulic servo shaking table based on the normalized least-mean-square adaptive algorithm
Authors: Jianjun Yao , Guilin Jiang , Duotao Di , Sheng Liu
Published: December 2011

For an electro-hydraulic servo shaking table, there are nonlinearities, which cause acceleration harmonic distortion when they corresponds to a sine acceleration excitation signal. The work here is to develop an acceleration harmonic identification algorithm by using the normalized least-mean-square (LMS) adaptive algorithm, whose weights are updated by the error between the acceleration response and the estimated acceleration signal. The input vector is generated by the reference harmonics and the [Formula: see text] phase shift. When the identification algorithm converges, the amplitude and phase of each harmonic can be computed from the weight vector. Experimental results show that the proposed harmonic identification has good real-time performance and a fast convergence rate, and it can identify harmonics on-line with high precision both in amplitude and in phase.
An experimental comparative study on non-conventional surface and interface damping techniques for automotive panel structures
Authors: Liu Yi , Zogg Markus , Ermanni Paolo
Published: December 2011

In order to increase the comfort of vehicle drivers, automotive panel structures are normally damped on their surfaces. Common surface damping treatments like free layer damping or constrained layer damping have the drawback of heavy weight and temperature as well as frequency dependent damping performance. New alternatives with simple structure, high robustness and light weight are sought. In this contribution, three different passive and active damping approaches were investigated: interface damping (ID), active constrained layer damping (ACLD) and particle damping (PD). They were surveyed under same boundary conditions and their performances were compared in terms of weight. The results show that ID strongly decouples the vibration from the source to the panel and provides steady performance over the whole frequency range. ACLD is a lightweight treatment with high damping capability for special mode shapes. PD is an effective simple damper providing excellent damping performance.
Chaos of a power system model and its control
Authors: Ma Cao-Yuan , Liu Jian-Hua , Wang Chong-Lin
Published: December 2011

The nonlinear dynamic characteristics of a simple three-bus power system mathematic model are studied, including phase diagrams and a bifurcation map. To control this undesirable chaos, sliding mode control law without buffeting is presented based on the LaSalle invariance principle, which considers the bounded disturbances. The theoretical analysis is in agreement with numerical simulation in that the designed controller could asymptotically stabilize the unstable power system to a typical steady-state. The research of this paper may help to maintain the power system's security operation.
Nonlinear finite element vibration analysis of double-walled carbon nanotubes based on Timoshenko beam theory
Authors: Ansari Reza , Hemmatnezhad Milad
Published: December 2011

The large-amplitude free vibration analysis of double-walled carbon nanotubes embedded in an elastic medium is investigated by means of a finite element formulation. A double-beam model is utilized in which the governing equations of layers are coupled with each other via the van der Waals interlayer forces. The Von Karman type nonlinear strain-displacement relationships are employed where the ends of the nanotube are constrained to move axially. The effects of the transverse shear deformation and rotary inertia are included based upon the Timoshenko beam theory. A superconvergent beam element which devoid the shear locking effect with displacement fields based on the first order shear deformation theory is used to study the geometric nonlinear effects on the vibrational characteristics of these beam-modeled nanotubes. In this kind of beam element, the interpolating functions are obtained using the exact solution of the static analysis of the beam. The finite element method is employed to discretize the nonlinear governing equations, which are then solved by the direct numerical integration technique to obtain the nonlinear vibration frequencies of double-walled carbon nanotubes with different boundary conditions. The effects of material constant of the surrounding elastic medium and the geometric parameters on the vibrational behavior are investigated. For a double-walled carbon nanotube with different boundary conditions between inner and outer tubes, the nonlinear frequencies are obtained apparently for the first time. The present numerical results are validated by comparing the linear and nonlinear frequencies of double-walled carbon nanotubes with those available in the literature where possible. This comparison illustrates that the present scheme yields very accurate results in predicting the nonlinear frequencies.
Advancing paternal age and simplex autism
Authors: Puleo Connor Morrow , Schmeidler James , Reichenberg Abraham , Kolevzon Alexander , Soorya Latha V , Buxbaum Joseph D , Silverman Jeremy M
Published: December 2011

De novo events appear more common in female and simplex autism spectrum disorder (ASD) cases and may underlie greater ASD risk in older fathers’ offspring. This study examined whether advancing paternal age predicts an increase in simplex ( n = 90) versus multiplex ASD cases ( n = 587) in 677 participants (340 families). Whether or not controlling for maternal age, results support a significant interaction of linear paternal age and sex of the child on simplex family type. Female ASD cases were significantly more likely to be simplex as paternal age increased, but the increase for males was not significant. Findings suggest that ASD arising from non-familial, de novo events may be far less prominent in males than in females, even if more prevalent in males, due to the substantially larger number of male cases attributable to other, more strongly male-biased risk factors.
Evaluation of the Indoor Environment of Comfort Houses: Qualitative and Quantitative Approaches
Authors: Brunsgaard Camilla , Heiselberg Per , Knudstrup Mary-Ann , Larsen Tine S.
Published: December 2011

Currently, the built environment accounts for about 40% of the total energy consumed in the European Union and this level is continuing to increase. This high level of energy consumption is partially a result of attempts to create an optimum indoor environment for the occupants of buildings. New buildings and renovation projects on existing buildings need to improve their energy performance while maintaining a good and healthy indoor environment. One way of saving energy is to build passive houses. This paper presents the results of a case study of some of the first certified passive houses in Denmark, called Comfort Houses. The indoor environment is evaluated using both quantitative measurements of these houses and qualitative interviews with the occupants about their experiences of the indoor environment. The combination of these two sets of knowledge leads to a more complete and holistic picture of the indoor environment. It is shown that attention needs to be paid to the objectives in the design process, the documentation of the designs and on the occupant’s lifestyle and behaviour. Finally, it is important to educate the occupants on how to live in an appropriate manner to achieve a comfortable indoor environment.
Low-Carbon Housings and Indoor Air Quality
Authors: Yu Chuck W.F. , Kim Jeong Tai
Published: December 2011

The purpose of this paper is to provide a review of the background information regarding low-carbon housings in the United Kingdom and to raise the concern of the possible high indoor pollution load due to the emissions from building materials and combustion products which would adversely affect the indoor air quality in air-tight buildings, especially homes. The standard guidelines given by the Building Regulations in the UK are reviewed especially in relation to mechanical ventilation with heat recovery systems. Also research literatures in relation to heat recovery ventilators and the use of air-cleaners from Korea, Hong Kong and China and from Europe are also included to illustrate the various possibilities to conserve energy and to achieve adequate ventilation with an improvement of indoor air quality. The effectiveness of using a heat recovery ventilator system and trickle ventilators in unoccupied super-energy-efficient test houses is illustrated by reviewing the long-term indoor volatile organic compound (VOC) concentrations in these test houses. The awareness of the issue is important for the future design and indoor air management of buildings, so as to provide adequate ventilation for living spaces without costing too much on energy efficiency.
Tourism image fragmentation: The case of Perpignan
Authors: Camprubi Raquel
Published: December 2011

Being recognized by academic literature that tourism destinations has a natural tendency to have more than one single image, this paper aims to analyse image fragmentation of an urban destination. Taking the city of Perpignan (France) as a case study, this phenomenon is analysed through a content analysis of 35 brochures and a cluster analysis, in order to find evidences and patterns of image fragmentation. Results show that tourism image is fragmented in four different profiles, although this situation is well managed by the Local Tourism Board, minimizing the possible effects of this situation.
The consequences of natural disasters in touristic destinations: The case of Madeira Island – Portugal
Authors: Machado Luiz Pinto
Published: December 2011

Today, destinations are evaluated by tourists according to safety and risk factors with regard to natural, terrorism and political problems. The portrayal of places in news reports can alter an area’s image dramatically, even in a short period of time. Often, natural disasters have impacts on the image of international destinations that endure for months if not years. Hence, media coverage of disasters or crises is of particular concern to destinations where such disasters occur. The Island of Madeira was not prepared for a catastrophe such as the one that occurred in February 2010, and its consequence has been a huge drop in the tourism industry. Driven by the generally accepted importance of destination image as a concept to destination marketers and academics, this article proposes that previous destination image research has tended to underestimate the importance of safety, security and risk. It also proposes a strategic approach to Destination management from proactive pre-crisis planning through to strategic implementation and finally evaluation and feedback.