WorldWideScience

Sample records for sandwich generation membership

  1. Membership

    CERN Multimedia

    Staff Association

    2016-01-01

    Join the Staff Association now for 2017, the remaining quarter of 2016 is free! The membership fee of the Staff Association is free for everyone joining during the last quarter of 2016. Take this opportunity to become a member of the SA. You can also enjoy our offers and partnerships, especially as we approach the holiday season. As a reminder, the membership fee is: 0.2 % of the annual basic salary for staff members with an indefinite contract (IC); the amount will be automatically charged on the salary of January; 50.00 CHF for staff members with a limited duration contract (LD), fellows and associated members of personnel.   Don’t wait any longer, join the Staff Association. We represent and defend all of you! More information on http://staff-association.web.cern.ch/

  2. Membership

    CERN Multimedia

    Staff Association

    2016-01-01

    Join the Staff Association now for 2017, the remaining quarter of 2016 is free! The membership fee of the Staff Association is free for everyone joining during the last quarter of 2016. Take this opportunity to become a member of the SA. You can also enjoy our offers and partnerships, especially as we approach the holiday season. As a reminder, the membership fee is: 0.2 % of the annual basic salary for staff members with an indefinite contract (IC); the amount will be automatically; 50.00 CHF for staff members with a limited duration contract (LD), fellows and associated members of personnel.   Don’t wait any longer, join the Staff Association that represents all of you! More information on http://staff-association.web.cern.ch/

  3. Sandwich-structured hollow fiber membranes for osmotic power generation

    KAUST Repository

    Fu, Feng Jiang

    2015-11-01

    In this work, a novel sandwich-structured hollow fiber membrane has been developed via a specially designed spinneret and optimized spinning conditions. With this specially designed spinneret, the outer layer, which is the most crucial part of the sandwich-structured membrane, is maintained the same as the traditional dual-layer membrane. The inner substrate layer is separated into two layers: (1) an ultra-thin middle layer comprising a high molecular weight polyvinylpyrrolidone (PVP) additive to enhance integration with the outer polybenzimidazole (PBI) selective layer, and (2) an inner-layer to provide strong mechanical strength for the membrane. Experimental results show that a high water permeability and good mechanical strength could be achieved without the expensive post treatment process to remove PVP which was necessary for the dual-layer pressure retarded osmosis (PRO) membranes. By optimizing the composition, the membrane shows a maximum power density of 6.23W/m2 at a hydraulic pressure of 22.0bar when 1M NaCl and 10mM NaCl are used as the draw and feed solutions, respectively. To our best knowledge, this is the best phase inversion hollow fiber membrane with an outer selective PBI layer for osmotic power generation. In addition, this is the first work that shows how to fabricate sandwich-structured hollow fiber membranes for various applications. © 2015 Elsevier B.V.

  4. Viewpoints of working sandwich generation women and occupational therapists on role balance strategies.

    Science.gov (United States)

    Evans, Kiah L; Girdler, Sonya J; Falkmer, Torbjorn; Richmond, Janet E; Wagman, Petra; Millsteed, Jeannine; Falkmer, Marita

    2017-09-01

    Occupational therapists need to be cognizant of evidence-based role balance advice and strategies that women with multigenerational caring responsibilities can implement independently or with minimal assistance, as role balance may not be the primary goal during many encounters with this population. Hence, this study aimed to identify the viewpoints on the most helpful role balance strategies for working sandwich generation women, both from their own perspectives and from the perspective of occupational therapists. This was achieved through a Q methodology study, where 54 statements were based on findings from interviews, sandwich generation literature and occupational therapy literature. In total, 31 working sandwich generation women and 42 occupational therapists completed the Q sort through either online or paper administration. The data were analysed using factor analysis with varimax rotation and were interpreted through collaboration with experts in the field. The findings revealed similarities between working sandwich generation women and occupational therapists, particularly in terms of advocating strategies related to sleep, rest and seeking practical assistance from support networks. Differences were also present, with working sandwich generation women viewpoints tending to emphasize strategies related to coping with a busy lifestyle attending to multiple responsibilities. In contrast, occupational therapy viewpoints prioritized strategies related to the occupational therapy process, such as goal setting, activity focused interventions, monitoring progress and facilitating sustainable outcomes.

  5. Combining photocatalytic hydrogen generation and capsule storage in graphene based sandwich structures

    Science.gov (United States)

    Yang, Li; Li, Xiyu; Zhang, Guozhen; Cui, Peng; Wang, Xijun; Jiang, Xiang; Zhao, Jin; Luo, Yi; Jiang, Jun

    2017-07-01

    The challenge of safe hydrogen storage has limited the practical application of solar-driven photocatalytic water splitting. It is hard to isolate hydrogen from oxygen products during water splitting to avoid unwanted reverse reaction or explosion. Here we propose a multi-layer structure where a carbon nitride is sandwiched between two graphene sheets modified by different functional groups. First-principles simulations demonstrate that such a system can harvest light and deliver photo-generated holes to the outer graphene-based sheets for water splitting and proton generation. Driven by electrostatic attraction, protons penetrate through graphene to react with electrons on the inner carbon nitride to generate hydrogen molecule. The produced hydrogen is completely isolated and stored with a high-density level within the sandwich, as no molecules could migrate through graphene. The ability of integrating photocatalytic hydrogen generation and safe capsule storage has made the sandwich system an exciting candidate for realistic solar and hydrogen energy utilization.

  6. Job Burnout and Couple Burnout in Dual-Earner Couples in the Sandwiched Generation

    Science.gov (United States)

    Pines, Ayala Malach; Neal, Margaret B.; Hammer, Leslie B.; Icekson, Tamar

    2011-01-01

    We use existential theory as a framework to explore the levels of and relationship between job and couple burnout reported by dual-earner couples in the "sandwich generation" (i.e., couples caring both for children and aging parents) in a sample of such couples in Israel and the United States. This comparison enables an examination of…

  7. Job Burnout and Couple Burnout in Dual-Earner Couples in the Sandwiched Generation

    Science.gov (United States)

    Pines, Ayala Malach; Neal, Margaret B.; Hammer, Leslie B.; Icekson, Tamar

    2011-01-01

    We use existential theory as a framework to explore the levels of and relationship between job and couple burnout reported by dual-earner couples in the "sandwich generation" (i.e., couples caring both for children and aging parents) in a sample of such couples in Israel and the United States. This comparison enables an examination of the…

  8. Changing Welfare States and the “Sandwich Generation” : Increasing Burden for the Next Generation?

    Directory of Open Access Journals (Sweden)

    Harald Künemund

    2006-12-01

    Full Text Available The burden placed on individuals aged 40 to 59 – especially on women – by competing demands from work and both older and younger family members is often addressed using the metaphor of the „sandwich gen-eration“. Based on a systematization of the definitions used in the litera-ture, empirical evidence on the frequency of such generational constella-tions and on their impact on the well-being of sandwiched adults will be presented. Analysing the second wave of the German Aging Survey shows that being sandwiched – defined as a generational constellation – is very common, but simultaneous care activities for both older and younger family members are rare, especially in combination with labour force participation, and that life satisfaction is not systematically related to being sandwiched. Implications for further research and future devel-opments will be discussed, especially with respect to changes in family structure (e.g. the beanpole family and changes in the amount of welfare state spending for the aged.

  9. DO GENERATIONAL MEMBERSHIP AND PSYCHOGRAPHIC CHARACTERISTICS INFLUENCE POSITIVE WORD OF MOUTH IN A UNIVERSITY CONTEXT?

    Directory of Open Access Journals (Sweden)

    Patrick Foley

    2012-01-01

    Full Text Available The specific question that this paper seeks to answer is: do psychographic culturally- anchored values act as antecedents to positive word of mouth intention independently of an individual's generational (Generation Y rather than Generation X membership? This question has important implications for service-based industries like universities. Results suggest that positive word of mouth intention is influenced by psychographic characteristics. Generation Y's positive word of mouth antecedents were: high collectivism, high uncertainty avoidance, and high power distance. Generation X's had only one antecedent, high collectivism. This paper concludes by outlining the areas for future research of Generation Y and the implication of this research for university leaders tasked with enhancing positive word of mouth in current students and alumni.

  10. Investigating the Relationship Between Family Caregiving and Chronic Diseases Among Sandwich Generation Females

    Directory of Open Access Journals (Sweden)

    Zangeneh Pour Zadeh

    2016-10-01

    Full Text Available Background In the recent years, chronic diseases have been identified as challenges of public health and healthcare and are the major causes of death in the female population. Females make up 75% of family caregivers. The sandwich generation females, who care for their aging parents while supporting their own children, encounter an increase in stress related to chronic diseases, but in some studies, the issue of care involves lower depression risk and more constructive psychological effects. Objectives The aim of the present study was to investigate the relationship between family caregiving and chronic diseases in sandwich generation females. Patients and Methods This study was a case-control study in Ahvaz in which 360 females including 180 sandwich generation caregivers and 180 caregivers of one generation (i.e. those only taking care of their own child were selected using the random cluster sampling method during six months. The two groups of participants were matched in terms of age, number of children under their care and their socioeconomic status. Data analysis was conducted using the Kolmogorov-Smirnov (K-S test or KS test and chi-square tests through the SPSS v.22 software. Results A statistically significant difference was found between the two groups in terms of the presence of chronic diseases (P = 0.001. There was a significant correlation between chronic diseases and number of children (P = 0.03, person receiving care (P = 0.004, educational level (P = 0.001, caregiving duration (P = 0.005, and socioeconomic status (P = 0.14. Chronic diseases in caregivers with more than four children, under diploma educational level, and with unfavorable socioeconomic status were more than others. Additionally, the occurrence of chronic diseases was more in females caring for their grandchildren. There was no significant correlation between chronic diseases and the age of caregivers (P > 0.05. Conclusions The current study revealed that a

  11. Working Sandwich Generation Women Utilize Strategies within and between Roles to Achieve Role Balance.

    Science.gov (United States)

    Evans, Kiah L; Millsteed, Jeannine; Richmond, Janet E; Falkmer, Marita; Falkmer, Torbjorn; Girdler, Sonya J

    2016-01-01

    Increasingly, women simultaneously balance the roles of mother, parental carer and worker. However, individual role balance strategies among these working 'sandwich' generation women have not been thoroughly explored. Eighteen women combining these three roles were interviewed about their individual role balance strategies. Findings were identified through the framework analysis technique, underpinned by the Model of Juggling Occupations. Achieving and maintaining role balance was explained as a complex process accomplished through a range of strategies. Findings revealed the women used six within-role balance strategies: living with integrity, being the best you can, doing what you love, loving what you do, remembering why and searching for signs of success. The women also described six between-role balance strategies: maintaining health and wellbeing, repressing perfectionism, managing time and energy, releasing responsibility, nurturing social connection and reciprocating. These findings provide a basis for health care providers to understand and potentially support working 'sandwich' generation women.

  12. Thermoelectric generator sandwiched in a crossflow heat exchanger with optimal connectivity between modules

    Energy Technology Data Exchange (ETDEWEB)

    Belanger, Simon [Departement de genie mecanique, Universite Laval, 1065, avenue de la Medecine, Quebec City, QC, G1V 0A6 (Canada); Gosselin, Louis, E-mail: Louis.Gosselin@gmc.ulaval.ca [Departement de genie mecanique, Universite Laval, 1065, avenue de la Medecine, Quebec City, QC, G1V 0A6 (Canada)

    2011-08-15

    Highlights: {yields} In this paper, we propose a numerical model for a crossflow heat exchanger with a thermoelectric generator sandwiched in its wall. {yields} The number of thermoelectric modules and the electrical connections between them is optimized with a genetic algorithm. {yields} Complex electric current topologies are achieved in order to maximize the total power output. - Abstract: The design of a thermoelectric generator sandwiched in the wall of a crossflow heat exchanger was optimized. A numerical model has been developed and validated. The objective function was the total power output. The design variables were the number of modules and the current in each control volume of the mesh. We also optimize directly the electrical topology of the system. A genetic algorithm was used to perform the optimizations. Complex optimal electrical topologies were achieved due to the non-uniform temperatures distributions in the heat exchanger.

  13. Generation of quasi-monoenergetic carbon ions accelerated parallel to the plane of a sandwich target

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J. W., E-mail: wang-jw@ile.osaka-u.ac.jp [Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan); Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Murakami, M.; Weng, S. M. [Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan); Xu, H. [National Laboratory for Parallel and Distributed Processing, School of Computer Science, National University of Defense Technology, Changsha 410073 (China); Ju, J. J.; Luan, S. X.; Yu, W. [Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2014-12-15

    A new ion acceleration scheme, namely, target parallel Coulomb acceleration, is proposed in which a carbon plate sandwiched between gold layers is irradiated with intense linearly polarized laser pulses. The high electrostatic field generated by the gold ions efficiently accelerates the embedded carbon ions parallel to the plane of the target. The ion beam is found to be collimated by the concave-shaped Coulomb potential. As a result, a quasi-monoenergetic and collimated C{sup 6+}-ion beam with an energy exceeding 10 MeV/nucleon is produced at a laser intensity of 5 × 10{sup 19} W/cm{sup 2}.

  14. Relation between Streaming Potential and Streaming Electrification Generated by Streaming of Water through a Sandwich-type Cell

    OpenAIRE

    Maruyama, Kazunori; NIKAIDO, Mitsuru; Hara, Yoshinori; Tanizaki, Yoshie

    2012-01-01

    Both streaming potential and accumulated charge of water flowed out were measured simultaneously using a sandwich-type cell. The voltages generated in divided sections along flow direction satisfied additivity. The sign of streaming potential agreed with that of streaming electrification. The relation between streaming potential and streaming electrification was explained from a viewpoint of electrical double layer in glass-water interface.

  15. Relation between Streaming Potential and Streaming Electrification Generated by Streaming of Water through a Sandwich-type Cell

    OpenAIRE

    Maruyama, Kazunori; NIKAIDO, Mitsuru; Hara, Yoshinori; Tanizaki, Yoshie

    2012-01-01

    Both streaming potential and accumulated charge of water flowed out were measured simultaneously using a sandwich-type cell. The voltages generated in divided sections along flow direction satisfied additivity. The sign of streaming potential agreed with that of streaming electrification. The relation between streaming potential and streaming electrification was explained from a viewpoint of electrical double layer in glass-water interface.

  16. Examining coping style and the relationship between stress and subjective well-being in Australia's 'sandwich generation'.

    Science.gov (United States)

    Gillett, Jade E; Crisp, Dimity A

    2017-06-02

    The sandwich generation represents adults, often in midlife, who care for both children and ageing parents/relatives. While the stress they experience has received some attention, little research has investigated the subjective well-being (SWB) of this population. This study examined the relationship between perceived stress and SWB and the moderating effect of coping style. Ninety-three participants (80 women), aged 23-63 years, completed an online survey measuring perceived stress, coping strategies, life satisfaction and positive and negative affect. Stress was negatively associated with SWB. While emotion- and problem-focused coping were directly associated with SWB outcomes, the only moderating effect found was for avoidance-focused coping (AFC). Specifically, AFC was associated with higher positive affect for those reporting lower stress. This study highlights the need to recognise the distinct circumstances that exist for the sandwich generation. Limitations and suggestions for future research are discussed. © 2017 AJA Inc.

  17. Developing a Theoretical Framework Using a Nursing Perspective to Investigate Perceived Health in the "Sandwich Generation" Group.

    Science.gov (United States)

    Oulevey Bachmann, Annie; Danuser, Brigitta; Morin, Diane

    2015-10-01

    Coexisting workloads from professional, household and family, and caregiving activities for frail parents expose middle-aged individuals, the so-called "Sandwich Generation", to potential health risks. Current trends suggest that this situation will continue or increase. Thus SG health promotion has become a nursing concern. Most existing research considers coexisting workloads a priori pathogenic. Most studies have examined the association of one, versus two, of these three activities with health. Few studies have used a nursing perspective. This article presents the development of a framework based on a nursing model. We integrated Siegrist's Effort-Reward Imbalance middle-range theory into "Neuman Systems Model". The latter was chosen for its salutogenic orientation, its attention to preventive nursing interventions and the opportunity it provides to simultaneously consider positive and negative perceptions of SG health and SG coexisting workloads. Finally, it facilitated a theoretical identification of health protective factors.

  18. Playful Membership

    DEFF Research Database (Denmark)

    Åkerstrøm Andersen, Niels; Pors, Justine Grønbæk

    2014-01-01

    This article studies the implications of current attempts by organizations to adapt to a world of constant change by introducing the notion of playful organizational membership. To this end we conduct a brief semantic history of organizational play and argue that when organizations play, employees...... are expected to engage in playful exploration of alternative selves. Drawing on Niklas Luhmann's theory of time and decision-making and Gregory Bateson's theory of play, the article analyses three empirical examples of how games play with conceptions of time. We explore how games represent an organizational...... desire to reach out - not just to the future - but to futures beyond the future presently imaginable. The article concludes that playful membership is membership through which employees are expected to develop a surplus of potential identities and continuously cross boundaries between real and virtual...

  19. Membership Satisfaction and the Cost of Membership

    DEFF Research Database (Denmark)

    Eskildsen, Jacob Kjær; Kristensen, Kai

    2011-01-01

    in membership satisfaction. Furthermore the cost of administration per member and membership satisfaction is found to be able to explain differences in membership loyalty when the 29 unemployment insurance funds are compared. Finally administration costs per member are found to be dependent on the number...

  20. Sandwich Panels

    Directory of Open Access Journals (Sweden)

    N. Ramachandran

    1963-05-01

    Full Text Available This introductory article give an insight into the different methods employed in the construction of Sandwich panels, their limitations and future design application for defence use as a structural element with one of the highest strength-weight ratios yet devised.

  1. State recognition of the viscoelastic sandwich structure based on the adaptive redundant second generation wavelet packet transform, permutation entropy and the wavelet support vector machine

    Science.gov (United States)

    Qu, Jinxiu; Zhang, Zhousuo; Wen, Jinpeng; Guo, Ting; Luo, Xue; Sun, Chuang; Li, Bing

    2014-08-01

    The viscoelastic sandwich structure is widely used in mechanical equipment, yet the structure always suffers from damage during long-term service. Therefore, state recognition of the viscoelastic sandwich structure is very necessary for monitoring structural health states and keeping the equipment running with high reliability. Through the analysis of vibration response signals, this paper presents a novel method for this task based on the adaptive redundant second generation wavelet packet transform (ARSGWPT), permutation entropy (PE) and the wavelet support vector machine (WSVM). In order to tackle the non-linearity existing in the structure vibration response, the PE is introduced to reveal the state changes of the structure. In the case of complex non-stationary vibration response signals, in order to obtain more effective information regarding the structural health states, the ARSGWPT, which can adaptively match the characteristics of a given signal, is proposed to process the vibration response signals, and then multiple PE features are extracted from the resultant wavelet packet coefficients. The WSVM, which can benefit from the conventional SVM as well as wavelet theory, is applied to classify the various structural states automatically. In this study, to achieve accurate and automated state recognition, the ARSGWPT, PE and WSVM are combined for signal processing, feature extraction and state classification, respectively. To demonstrate the effectiveness of the proposed method, a typical viscoelastic sandwich structure is designed, and the different degrees of preload on the structure are used to characterize the various looseness states. The test results show that the proposed method can reliably recognize the different looseness states of the viscoelastic sandwich structure, and the WSVM can achieve a better classification performance than the conventional SVM. Moreover, the superiority of the proposed ARSGWPT in processing the complex vibration response

  2. Sandwich construction

    Science.gov (United States)

    Marshall, A.

    A form of composites known as structural sandwich construction is presented in terms of materials used, design details for solving edging and attachment problems, and charts of design material analysis. Sandwich construction is used in nearly all commercial airliners and helicopters, and military air and space vehicles, and it is shown that this method can stiffen a structure without causing a weight increase. The facing material can be made of 2024 or 7075 aluminum alloy, titanium, or stainless steel, and the core material can be wood or foam. The properties of paper honeycomb and various aluminum alloy honeycombs are presented. Factors pertaining to adhesive materials are discussed, including products given off during cure, bonding pressure, and adaptability. Design requirements and manufacturing specifications are resolved using numerous suggestions.

  3. Membership Satisfaction and the Cost of Membership

    DEFF Research Database (Denmark)

    Eskildsen, Jacob Kjær; Kristensen, Kai

    2011-01-01

    This article suggests a framework for measuring membership satisfaction based on a literature study. The framework is tested on data from more than 8800 members from 29 different Danish unemployment insurance funds. The framework fits the data well and is able to explain 83% of the variation...... in membership satisfaction. Furthermore the cost of administration per member and membership satisfaction is found to be able to explain differences in membership loyalty when the 29 unemployment insurance funds are compared. Finally administration costs per member are found to be dependent on the number...

  4. Sensitive Glycoprotein Sandwich Assays by the Synergistic Effect of In Situ Generation of Raman Probes and Plasmonic Coupling of Ag Core-Au Satellite Nanostructures.

    Science.gov (United States)

    Bi, Xiaoshuang; Li, Xueyuan; Chen, Dong; Du, Xuezhong

    2016-05-01

    Sensitive surface-enhanced Raman scattering (SERS) assays of glycoproteins have been proposed using p-aminothiophenol (PATP)-embedded Ag core-Au satellite nanostructures modified with p-mercaptophenylboronic acid (PMBA) and the self-assembled monolayer of PMBA on a smooth gold-coated wafer. The apparent Raman probe PATP on the surfaces of the Ag cores underwent a photodimerization to generate 4,4'-dimercaptoazobenzene (DMAB) in situ upon excitation of laser, and the in situ generated DMAB acted as the actual Raman probe with considerably strong SERS signals, which was further enhanced by the plasmonic coupling of the Ag core-Au satellite nanostructures due to the synergistic effect. The sandwich assays of glycoproteins showed high sensitivity and excellent selectivity against nonglycoproteins. The Ag core-Au satellite SERS nanostructures can be used for highly sensitive SERS assays of other analytes.

  5. Solar hydrogen generation by a CdS-Au-TiO2 sandwich nanorod array enhanced with Au nanoparticle as electron relay and plasmonic photosensitizer.

    Science.gov (United States)

    Li, Jiangtian; Cushing, Scott K; Zheng, Peng; Senty, Tess; Meng, Fanke; Bristow, Alan D; Manivannan, Ayyakkannu; Wu, Nianqiang

    2014-06-11

    This paper presents a sandwich-structured CdS-Au-TiO2 nanorod array as the photoanode in a photoelectrochemical cell (PEC) for hydrogen generation via splitting water. The gold nanoparticles sandwiched between the TiO2 nanorod and the CdS quantum dot (QD) layer play a dual role in enhancing the solar-to-chemical energy conversion efficiency. First, the Au nanoparticles serve as an electron relay, which facilitates the charge transfer between CdS and TiO2 when the CdS QDs are photoexcited by wavelengths shorter than 525 nm. Second, the Au nanoparticles act as a plasmonic photosensitizer, which enables the solar-to-hydrogen conversion at wavelengths longer than the band edge of CdS, extending the photoconversion wavelength from 525 to 725 nm. The dual role of Au leads to a photocurrent of 4.07 mA/cm(2) at 0 V (vs Ag|AgCl) under full solar spectrum irradiation and a maximum solar-to-chemical energy conversion efficiency of 2.8%. An inversion analysis is applied to the transient absorption spectroscopy data, tracking the transfer of electrons and holes in the heterostructure, relating the relaxation dynamics to the underlying coupled rate equation and revealing that trap-state Auger recombination is a dominant factor in interfacial charge transfer. It is found that addition of Au nanoparticles increases the charge-transfer lifetime, reduces the trap-state Auger rate, suppresses the long-time scale back transfer, and partially compensates the negative effects of the surface trap states. Finally, the plasmonic energy-transfer mechanism is identified as direct transfer of the plasmonic hot carriers, and the interfacial Schottky barrier height is shown to modulate the plasmonic hot electron transfer and back transfer. Transient absorption characterization of the charge transfer shows defect states cannot be ignored when designing QD-sensitized solar cells. This facile sandwich structure combines both the electrical and the optical functions of Au nanoparticles into a

  6. Sandwich DIY

    Institute of Scientific and Technical Information of China (English)

    肖蕾

    2006-01-01

    我们都知道sandwich是一种方便食品,就是在两片面包中加上一些肉和蔬菜。Sandwich这个名字来源于英国的一位桑威治伯爵(Earl of Sandwich)。据说这位伯爵嗜赌如命,就是到吃饭的时候也不愿停下来。于是他就叫侍者把肉、蛋、菜夹在面包片中,让他拿在手上边赌边吃。后来人们就把这种夹馅面包叫做sandwich。现在sandwich已成为风靡世界的快餐食品(snack)了。Sandwich的做法其实很简单。如果你有两片面包,你几乎可以在这两片面包之间夹上任何食物来给自己做一个三明治。下面就让我们试一试,做一个三明治来吃。第一步:在一片面包上抹上黄油(butter)或植物黄油,在另一片面包上抹上蛋黄酱(mayonnaise)和芥末酱(mustard)。喜欢吃番茄酱(catsup)也可以放番茄酱!第二步:把花生酱(peanut butter)或者乳酪片(cream)、熟肉片放在涂了黄油的面包片上。想吃什么肉就放什么肉,香肠也可以!第三步:在乳酪上面放酸黄瓜片、番茄片和生菜。也可以根据个人的口味再放些乳酪、芥末酱和(或)番茄酱、洋葱、辣椒、盐、黑胡椒和醋。第四步:将第二片面包盖在上面,就做成了一个sand...

  7. Membership Survey Results

    Directory of Open Access Journals (Sweden)

    Dennis M Bowie

    2004-01-01

    Full Text Available In an effort to gather feedback from Canadian Thoracic Society (CTS members, the Executive sent out a survey to the membership and received replies from approximately one-third of the membership. This was an attempt to look at the role of the CTS and what the members wanted from the CTS.

  8. A hydrophilic inorganic framework based on a sandwich polyoxometalate: unusual chemoselectivity for aldehydes/ketones with in situ generated hydroxylamine.

    Science.gov (United States)

    Xing, Songzhu; Han, Qiuxia; Shi, Zhuolin; Wang, Shugai; Yang, PeiPei; Wu, Qiang; Li, Mingxue

    2017-08-16

    A hydrophilic inorganic porous catalyst was prepared via the hydrothermal method. The combination of [WZn3(H2O)2(ZnW9O34)2](12-) and Co(ii) provides a synergistical catalytic way to promote oximation of aldehyde/ketone with in situ generated hydroxylamine that initially produces an oxime, which further either dehydrates into a nitrile or undergoes a Beckmann rearrangement to form an amide.

  9. The sandwich sign

    Directory of Open Access Journals (Sweden)

    Nasreen Mahomed

    2012-09-01

    Full Text Available The sandwich sign refers to the sandwiching of mesenteric vessels and fat by enlarged mesenteric nodes on cross-sectional imaging, commonly occurring in lymphoma, but not specific to lymphoma. The sign is radiologically indistinguishable from post-transplant lymphoproliferative disorders. The radiological significance of the sandwich sign is in suggesting the diagnosis of lymphoma so that appropriate treatment may be initiated early as the tumour has a rapid growth pattern.

  10. Thermolysis of Half-Sandwich Vanadium(V) Imido Complexes to Generate Vanadium(III) Imido Species via a Vanadium(IV) Intermediate

    NARCIS (Netherlands)

    Batinas, Aurora A.; Dam, Jeroen; Meetsma, Auke; Hessen, Bart; Bouwkamp, Marco W.

    2010-01-01

    Thermolysis of half-sandwich vanadium imido complexes Cp(RN)V(i-Pr(2)N)Me (R = p-Tol, 1a; R = t-Bu, 1b) results in a mixture of products, including vanadium(IV) dimers [CpVMe](2)(mu-RN)(2), i-Pr(2)NH, i-PrNCMe(2), CH(4), and one or more paramagnetic species. In the presence of dmpe (dmpe =

  11. Sandwich classification theorem

    Directory of Open Access Journals (Sweden)

    Alexey Stepanov

    2015-09-01

    Full Text Available The present note arises from the author's talk at the conference ``Ischia Group Theory 2014''. For subgroups FleN of a group G denote by Lat(F,N the set of all subgroups of N , containing F . Let D be a subgroup of G . In this note we study the lattice LL=Lat(D,G and the lattice LL ′ of subgroups of G , normalized by D . We say that LL satisfies sandwich classification theorem if LL splits into a disjoint union of sandwiches Lat(F,N G (F over all subgroups F such that the normal closure of D in F coincides with F . Here N G (F denotes the normalizer of F in G . A similar notion of sandwich classification is introduced for the lattice LL ′ . If D is perfect, i.,e. coincides with its commutator subgroup, then it turns out that sandwich classification theorem for LL and LL ′ are equivalent. We also show how to find basic subroup F of sandwiches for LL ′ and review sandwich classification theorems in algebraic groups over rings.

  12. Meteor Stream Membership Criteria

    CERN Document Server

    Klacka, J

    2000-01-01

    Criteria for the membership of individual meteors in meteor streams are discussed from the point of view of their mathematical and also physical properties. Discussion is also devoted to the motivation. It is shown that standardly used criteria (mainly D-criterion of Southworth and Hawkins, 1963) have unusual mathematical properties in the sense of a term ``distance'', between points in a phase space, and, physical motivation and realization for the purpose of obtaining their final form is not natural and correct, and, moreover, they lead also to at least surprising astrophysical results. General properties of possible criteria are discussed. A new criterion for the membership in meteor streams is suggested. It is based on probability theory. Finally, a problem of meteor orbit determination for known parent body is discussed.

  13. AGU membership applications

    Science.gov (United States)

    Applications for membership have been received from the following individuals. The letter after the name denotes the proposed primary section affiliation.Raffi Aroian (P), David Baker (P), D. Craig Barilotti (O), Stephen J. Barnes (V), Thomas O. Barnwell (H), Robert P. Bessette (G), Brian Bicknell (H), William Blumberg (A), Michele A. Boccadoro (G), Richard Boylan (T), Robert C. Bucknam (T), Roman J. Budzianowski (H), Bruce M. Crowe (V), Charles G. Cunningham (V).

  14. AGU membership applications

    Science.gov (United States)

    Applications for membership have been received from the following individuals. The letter after the name denotes the proposed primary section affiliation.Henry D. I. Abarbanel (O), Julia C. Allen (H), Gwendolyn L. Anson (GP), Andrew Bakun (O), C. A. Bengtson (T), Patricia A. Berge (S), Peter R. Betzer (O), Pierre Boivin (V), Michael V. Capobianco (P), Martin C. Chapman (S), Chu-Yung Chen (V), Timothy J. Clarke (S), Steven C. Constable (GP), Michele Dermer (H), G. M. Dow (T), Carl E. Draper (G), Dean A. Dunn (O), I. B. Everingham (S).

  15. Predicting safe sandwich production

    DEFF Research Database (Denmark)

    Birk, Tina; Duan, Zhi; Møller, Cleide Oliveira de Almeida

    2014-01-01

    and serving. However, Danish sandwich producing companies find it challenging to comply with this and have expressed a need for more flexibility. The Danish guidelines do allow for a prolongation of the acceptable time outside the cold chain, if the safety of the specific production can be documented....... There is, therefore, room for developing targeted tools for evaluating the time-temperature scenarios in sandwich production. This study describes a decision support tool developed to offer the producers more flexibility. Based on time/temperature measurements obtained during preparation combined......Time and temperature control is crucial to avoid growth of pathogens during production and serving of cold ready-to-eat meals. The Danish guidelines state that chilled foods, such as sandwiches, should not be outside the cold chain for more than 3 hours including the time for preparation...

  16. On Sandwiched Singularities

    OpenAIRE

    Möhring, Konrad

    2004-01-01

    Sandwich-Singularitäten sind die Singularitäten auf derNormalisierung von Aufblasungen eines regulärenFlächenkeimes. In der Arbeit wird ein enger Zusammenhangzwischen Topologie und Deformationstheorie vonSandwich-Singularitäten einerseits und ebenenKurvensingularitäten andererseits dargestellt. NeueErgebnisse betreffen u.a. Deformationen vonnulldimensionalen komplexen Räumen in der Ebene, die durchvollständige Ideale beschrieben werden, z.B. wann'simultanes Aufblasen' der Fasern einer solchen...

  17. A multifunctional heat pipe sandwich panel structure

    Energy Technology Data Exchange (ETDEWEB)

    Queheillalt, Douglas T.; Wadley, Haydn N.G. [University of Virginia, Department of Materials Science and Engineering, 140 Chemistry Way, P.O. Box 400745, Charlottesville, VA 22904 (United States); Carbajal, Gerardo [University of Turabo, School of Engineering, P.O. Box 3030, Gurabo 00778 (Puerto Rico); Peterson, G.P. [University of Colorado at Boulder, 914 Broadway, Boulder, CO 80309 (United States)

    2008-01-15

    A multifunctional sandwich panel combining efficient structural load support and thermal management characteristics has been designed and experimentally assessed. The concept is based upon a truncated, square honeycomb sandwich structure. In closed cell honeycomb structures, the transport of heat from one face to the other occurs by a combination of conduction through the webs and convection/radiation within the cells. Here, much more effective heat transport is achieved by multifunctionally utilizing the core as a heat pipe sandwich panel. Its interior consists of a 6061 aluminum truncated-square honeycomb core covered with a stochastic open-cell nickel foam wick. An electroless nickel plating barrier layer inhibited the chemical reaction between the deionized water working fluid and the aluminum structure, retarding the generation of non-condensable hydrogen gas. A thermodynamic model was used to guide the design of the heat pipe sandwich panel. We describe the results of a series of experiments that validate the operational principle of the multifunctional heat pipe sandwich panel and characterize its transient response to an intense localized heat source. The systems measured thermal response to a localized heat source agrees well with that predicted by a finite difference method model used to predict the thermal response. (author)

  18. Sandwich Panels Evaluated With Ultrasonic Spectroscopy

    Science.gov (United States)

    Cosgriff, Laura M.

    2004-01-01

    Enhanced, lightweight material systems, such as 17-4PH stainless steel sandwich panels are being developed for use as fan blades and fan containment systems for next-generation engines. The bond strength between the core and face sheets is critical in maintaining the structural integrity of the sandwich structure. To improve the inspection and production of these systems, researchers at the NASA Glenn Research Center are using nondestructive evaluation (NDE) techniques, such as ultrasonic spectroscopy, to evaluate the brazing quality between the face plates and the metallic foam core. The capabilities and limitations of a swept-frequency approach to ultrasonic spectroscopy were evaluated with respect to these sandwich structures. This report discusses results from three regions of a sandwich panel representing different levels of brazing quality between the outer face plates and a metallic foam core. Each region was investigated with ultrasonic spectroscopy. Then, on the basis of the NDE results, three shear specimens sectioned from the sandwich panel to contain each of these regions were mechanically tested.

  19. Origin of Sandwich

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    In every language there are words that have some interesting stories behind them. The word “sandwich” forexample, is very common in English. If we want to know the story behind it, we must know something about an English nobleman named Sandwich who lived in the 18th century.

  20. Making a Sandwich

    Institute of Scientific and Technical Information of China (English)

    郭富强

    2011-01-01

    Do you like eating sandwiches? Here is a recipe(做法) for a fruit sandwich.First , you should put butter(黄油)on two slices(片) of bread. Next, peel(剥开) three bananas. Now cut up(切碎) these three bananas and apple.

  1. Advanced Concepts in Fuzzy Logic and Systems with Membership Uncertainty

    CERN Document Server

    Starczewski, Janusz T

    2013-01-01

    This book generalizes fuzzy logic systems for different types of uncertainty, including - semantic ambiguity resulting from limited perception or lack of knowledge about exact membership functions - lack of attributes or granularity arising from discretization of real data - imprecise description of membership functions - vagueness perceived as fuzzification of conditional attributes. Consequently, the membership uncertainty can be modeled by combining methods of conventional and type-2 fuzzy logic, rough set theory and possibility theory.            In particular, this book provides a number of formulae for implementing the operation extended on fuzzy-valued fuzzy sets and presents some basic structures of generalized uncertain fuzzy logic systems, as well as introduces several of methods to generate fuzzy membership uncertainty. It is desirable as a reference book for under-graduates in higher education, master and doctor graduates in the courses of computer science, computational intelligence, or...

  2. Discriminative Mixed-Membership Models

    Data.gov (United States)

    National Aeronautics and Space Administration — Although mixed-membership models have achieved great success in unsupervised learning, they have not been widely applied to classification problems. In this paper,...

  3. Optimal Distinctiveness Signals Membership Trust.

    Science.gov (United States)

    Leonardelli, Geoffrey J; Loyd, Denise Lewin

    2016-07-01

    According to optimal distinctiveness theory, sufficiently small minority groups are associated with greater membership trust, even among members otherwise unknown, because the groups are seen as optimally distinctive. This article elaborates on the prediction's motivational and cognitive processes and tests whether sufficiently small minorities (defined by relative size; for example, 20%) are associated with greater membership trust relative to mere minorities (45%), and whether such trust is a function of optimal distinctiveness. Two experiments, examining observers' perceptions of minority and majority groups and using minimal groups and (in Experiment 2) a trust game, revealed greater membership trust in minorities than majorities. In Experiment 2, participants also preferred joining minorities over more powerful majorities. Both effects occurred only when minorities were 20% rather than 45%. In both studies, perceptions of optimal distinctiveness mediated effects. Discussion focuses on the value of relative size and optimal distinctiveness, and when membership trust manifests.

  4. On the ALA Membership Pyramid

    Directory of Open Access Journals (Sweden)

    Emily Ford

    2008-10-01

    Full Text Available “…i [sic] only renew [my ALA membership] out of a sense of professional obligation, and also because of the fear that i’ll [sic] put it on my resume and get busted as not being a member.” –c-dog Membership in the American Library Association means professionals are bound together by the tenets of librarianship. Technically, this [...

  5. Sandwiched composites in aerospace engineering

    OpenAIRE

    Nunes, J. P.; Silva,J.F.

    2016-01-01

    This chapter considers sandwiched composites used in aerospace applications. Typical sandwich composites consist of two thin, stiff, high-strength facing skins separated by a thick and light core. New developments in the type of face and core materials, production methods and joining and repair techniques are discussed in this chapter. It also discusses various properties as well as their main design methods for existing and future applications of sandwiched composites.

  6. Cluster Membership Probability: Polarimetric Approach

    CERN Document Server

    Medhi, Biman J

    2013-01-01

    Interstellar polarimetric data of the six open clusters Hogg 15, NGC 6611, NGC 5606, NGC 6231, NGC 5749 and NGC 6250 have been used to estimate the membership probability for the stars within them. For proper-motion member stars, the membership probability estimated using the polarimetric data is in good agreement with the proper-motion cluster membership probability. However, for proper-motion non-member stars, the membership probability estimated by the polarimetric method is in total disagreement with the proper-motion cluster membership probability. The inconsistencies in the determined memberships may be because of the fundamental differences between the two methods of determination: one is based on stellar proper-motion in space and the other is based on selective extinction of the stellar output by the asymmetric aligned dust grains present in the interstellar medium. The results and analysis suggest that the scatter of the Stokes vectors q(%) and u(%) for the proper-motion member stars depends on the ...

  7. The Simultaneous Membership Problem for Chordal, Comparability and Permutation graphs

    CERN Document Server

    Jampani, Krishnam Raju

    2008-01-01

    In this paper we introduce the 'simultaneous membership problem', defined for any graph class C characterized in terms of representations, e.g. any class of intersection graphs. Two graphs G_1 and G_2, sharing some vertices X (and the corresponding induced edges), are said to be 'simultaneous members' of graph class C, if there exist representations R_1 and R_2 of G_1 and G_2 that are "consistent" on X. Equivalently (for the classes C that we consider) there exist edges E' between G_1-X and G_2-X such that G_1 \\cup G_2 \\cup E' belongs to class C. Simultaneous membership problems have application in any situation where it is desirable to consistently represent two related graphs, for example: interval graphs capturing overlaps of DNA fragments of two similar organisms; or graphs connected in time, where one is an updated version of the other. Simultaneous membership problems are related to simultaneous planar embeddings, graph sandwich problems and probe graph recognition problems. In this paper we give effici...

  8. Structural Analysis of Sandwich Foam Panels

    Energy Technology Data Exchange (ETDEWEB)

    Kosny, Jan [ORNL; Huo, X. Sharon [Tennessee Technological University

    2010-04-01

    The Sandwich Panel Technologies including Structural Insulated Panels (SIPs) can be used to replace the conventional wooden-frame construction method. The main purpose of this Cooperative Research and Development Agreement (CRADA) between UT-Battelle, LLC and SGI Venture, Inc. was to design a novel high R-value type of metal sandwich panelized technology. This CRADA project report presents design concept discussion and numerical analysis results from thermal performance study of this new building envelope system. The main objective of this work was to develop a basic concept of a new generation of wall panel technologies which will have R-value over R-20 will use thermal mass to improve energy performance in cooling dominated climates and will be 100% termite resistant. The main advantages of using sandwich panels are as follows: (1) better energy saving structural panels with high and uniform overall wall R-value across the elevation that could not be achieved in traditional walls; and (2) reducing the use of raw materials or need for virgin lumber. For better utilization of these Sandwich panels, engineers need to have a thorough understanding of the actual performance of the panels and system. Detailed analysis and study on the capacities and deformation of individual panels and its assembly have to be performed to achieve that goal. The major project activity was to conduct structural analysis of the stresses, strains, load capacities, and deformations of individual sandwich components under various load cases. The analysis simulated the actual loading conditions of the regular residential building and used actual material properties of the steel facings and foam.

  9. Ultrasonic Spectroscopy of Stainless Steel Sandwich Panels

    Science.gov (United States)

    Cosgriff, Laura M.; Lerch, Bradley A.; Hebsur, Mohan G.; Baaklini, George Y.; Ghosn, Louis J.

    2003-01-01

    Enhanced, lightweight material systems, such as 17-4PH stainless steel sandwich panels are being developed for use as fan blades and fan containment material systems for next generation engines. In order to improve the production for these systems, nondestructive evaluation (NDE) techniques, such as ultrasonic spectroscopy, are being utilized to evaluate the brazing quality between the 17-4PH stainless steel face plates and the 17-4PH stainless steel foam core. Based on NDE data, shear tests are performed on sections representing various levels of brazing quality from an initial batch of these sandwich structures. Metallographic characterization of brazing is done to corroborate NDE findings and the observed shear failure mechanisms.

  10. The asymmetric sandwich theorem

    CERN Document Server

    Simons, Stephen

    2011-01-01

    We discuss the asymmetric sandwich theorem, a generalization of the Hahn-Banach theorem. As applications, we derive various results on the existence of linear functionals that include bivariate, trivariate and quadrivariate generalizations of the Fenchel duality theorem. Most of the results are about affine functions defined on convex subsets of vector spaces, rather than linear functions defined on vector spaces. We consider both results that use a simple boundedness hypothesis (as in Rockafellar's version of the Fenchel duality theorem) and also results that use Baire's theorem (as in the Robinson-Attouch-Brezis version of the Fenchel duality theorem). This paper also contains some new results about metrizable topological vector spaces that are not necessarily locally convex.

  11. Fracture of sandwiched composites

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Weh-Huei.

    1989-01-01

    Fracture of a pair of collinear cracks in various materials, such as an isotropic strip, an orthotropic strip, a bonded isotropic adhesive layer, and sandwiched orthotropic layers, is investigated. The crack surfaces are subjected to an arbitrary opening pressure p(x). The problems are formulated in terms of Fredholm integral equation of the second kind by making use the techniques of Fourier transform and finite Hilbert transform. In case of uniform opening pressure p(x)={sigma}, exact expressions for the stress intensity factors and the shape of deformed crack are obtained. Numerical calculations are carried out to study the effects of various boundary geometries and material properties on the fracture of the chosen materials.

  12. Typicality, graded membership, and vagueness.

    Science.gov (United States)

    Hampton, James A

    2007-05-01

    This paper addresses theoretical problems arising from the vagueness of language terms, and intuitions of the vagueness of the concepts to which they refer. It is argued that the central intuitions of prototype theory are sufficient to account for both typicality phenomena and psychological intuitions about degrees of membership in vaguely defined classes. The first section explains the importance of the relation between degrees of membership and typicality (or goodness of example) in conceptual categorization. The second and third section address arguments advanced by Osherson and Smith (1997), and Kamp and Partee (1995), that the two notions of degree of membership and typicality must relate to fundamentally different aspects of conceptual representations. A version of prototype theory-the Threshold Model-is proposed to counter these arguments and three possible solutions to the problems of logical selfcontradiction and tautology for vague categorizations are outlined. In the final section graded membership is related to the social construction of conceptual boundaries maintained through language use.

  13. 7 CFR 981.31 - Membership representation.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Membership representation. 981.31 Section 981.31 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Regulating Handling Almond Board of California § 981.31 Membership representation. Membership of the Board...

  14. 12 CFR 575.5 - Membership rights.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Membership rights. 575.5 Section 575.5 Banks... Membership rights. (a) Depositors and borrowers of resulting associations, acquiree associations, and... existing and future depositors of the resulting association the same membership rights in the...

  15. Comparative fluorescence two-dimensional gel electrophoresis using a gel strip sandwich assembly for the simultaneous on-gel generation of a reference protein spot grid.

    Science.gov (United States)

    Ackermann, Doreen; Wang, Weiqun; Streipert, Benjamin; Geib, Birgit; Grün, Lothar; König, Simone

    2012-05-01

    The comparison of proteins separated on 2DE is difficult due to gel-to-gel variability. Here, a method named comparative fluorescence gel electrophoresis (CoFGE) is presented, which allows the generation of an artificial protein grid in parallel to the separation of an analytical sample on the same gel. Different fluorescent stains are used to distinguish sample and marker on the gel. The technology combines elements of 1DE and 2DE. Special gel combs with V-shaped wells are placed in a stacking gel above the pI strip. Proteins separated on the pI strip are electrophoresed at the same time as marker proteins (commercially available purified protein of different molecular weight) placed in V-wells. In that way, grids providing approximately 100 nodes as landmarks for the determination of protein spot coordinates are generated. Data analysis is possible with commercial 2DE software capable of warping. The method improves comparability of 2DE protein gels, because they are generated in combination with regular in-gel anchor points formed by protein standards. This was shown here for two comparative experiments with three gels each using Escherichia coli lysate. For a set of 47 well-defined samples spots, the deviation of the coordinates was improved from 7% to less than 1% applying warping using the marker grid. Conclusively, as long as the same protein markers, the same size of pI-strips and the same technology are used, gel matching is reproducibly possible. This is an important advancement for projects involving comparison of 2DE-gels produced over several years and in different laboratories. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Generation of a quasi-monoenergetic high energy proton beam from a vacuum-sandwiched double layer target irradiated by an ultraintense laser pulse

    Energy Technology Data Exchange (ETDEWEB)

    Nam Kim, Kyung; Lee, Kitae, E-mail: klee@kaeri.re.kr; Hee Park, Seong; Young Lee, Ji; Uk Jeong, Young; Vinokurov, Nikolay [Center for Quantum-Beam-based Radiation Research, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Gi Kim, Yong [Department of Physics, Kongju National University, Kongju (Korea, Republic of)

    2014-04-15

    An acceleration mechanism to generate a high energy proton beam with a narrow energy spread in the laser-induced plasma acceleration of a proton beam is proposed; this mechanism employs two thin foils separated by a narrow vacuum gap. Instead of a thin sheath field at the plasma surfaces, it utilizes an electrostatic field formed in the bulk of the plasma. From a one-dimensional fluid analysis, it has been found that with an appropriate target thickness, protons on the front surface of the second layer can be fed into the plasma, in which the protons are accelerated by an electrostatic field built into the bulk of the plasma. This leads to a proton beam with higher energy and a narrower energy spread than those accelerated at the rear surface of the second layer. The acceleration mechanism is also verified by a two-dimensional particle-in-cell simulation. With a 27-fs long and 2×10{sup 19} W/cm{sup 2} intense laser pulse, a proton beam with an 18-MeV peak energy and a 35% energy spread is generated. The peak energy is higher than that from the rear surface of the second layer by a factor of 3.

  17. Development of Aircraft Sandwich Parts

    Directory of Open Access Journals (Sweden)

    J. Křena

    2000-01-01

    Full Text Available The presented paper shows the design and development process of sandwich parts. A spoiler plate and a main landing gear door are developed. Sandwich parts are made of C/E composite facings and a foam core. FE models have been used for optimization of structures. Emphasis has been placed on deformations of parts under a few load cases. Experimental tests have been used for a verification of structure parts loaded by concentrated forces.

  18. Assessment of the role of in situ generated (E)-2,4-diene-valproic acid in the toxicity of valproic acid and (E)-2-ene-valproic acid in sandwich-cultured rat hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Surendradoss, Jayakumar; Chang, Thomas K.H.; Abbott, Frank S., E-mail: frank.abbott@ubc.ca

    2012-11-01

    Valproic acid (VPA) undergoes cytochrome P450-mediated desaturation to form 4-ene-VPA, which subsequently yields (E)-2,4-diene-VPA by β-oxidation. Another biotransformation pathway involves β-oxidation of VPA to form (E)-2-ene-VPA, which also generates (E)-2,4-diene-VPA by cytochrome P450-mediated desaturation. Although the synthetic form of (E)-2,4-diene-VPA is more hepatotoxic than VPA as shown in various experimental models, there is no conclusive evidence to implicate the in situ generated (E)-2,4-diene-VPA in VPA hepatotoxicity. The present study investigated the effects of modulating the in situ formation of (E)-2,4-diene-VPA on markers of oxidative stress (formation of 2′,7′-dichlorofluorescein; DCF), steatosis (accumulation of BODIPY 558/568 C{sub 12}), necrosis (release of lactate dehydrogenase; LDH), and on cellular total glutathione (GSH) levels in sandwich-cultured rat hepatocytes treated with VPA or (E)-2-ene-VPA. Treatment with either of these chemicals alone increased each of the toxicity endpoints. In VPA-treated hepatocytes, (E)-2,4-diene-VPA was detected only at trace levels, even after phenobarbital (PB) pretreatment and there was no effect on the toxicity of VPA. Furthermore, pretreatment with a cytochrome P450 enzyme inhibitor, 1-aminobenzotriazole (1-ABT), did not influence the extent of VPA toxicity in both PB-pretreated and vehicle-pretreated hepatocytes. However, in (E)-2-ene-VPA-treated hepatocytes, PB pretreatment greatly enhanced the levels of (E)-2,4-diene-VPA and this was accompanied by a further enhancement of the effects of (E)-2-ene-VPA on DCF formation, BODIPY accumulation, LDH release, and GSH depletion. Pretreatment with 1-ABT reduced the concentrations of (E)-2,4-diene-VPA and the extent of (E)-2-ene-VPA toxicity; however, this occurred in PB-pretreated hepatocytes, but not in control hepatocytes. In conclusion, in situ generated (E)-2,4-diene-VPA is not responsible for the hepatocyte toxicity of VPA, whereas it

  19. Fuzzy Programming With Quadratic Membership Functions For Multi-objective Transportation Problem

    Directory of Open Access Journals (Sweden)

    Satyanarayana Murthy Akkapeddi

    2015-08-01

    Full Text Available In the present paper, a fuzzy programming model with quadratic membership functions has been developed for the solution of a Multi-Objective Transportation problem. In literature, several fuzzy programming approaches exist with various types of membership functions such as linear, exponential, hyperbolic etc. These membership functions are defined, by taking the lower and upper values of the objective functions into account.  In some cases, these methods fail to obtain an integer compromise optimal solution. In the present method, two coefficients of the quadratic membership functions are determined by the lower and upper values of the objective functions. The other coefficient is taken as a variable in the fuzzy programming approach. This means that the membership curve is fixed at the two end points and set free in between. Application of the method on numerical examples proved that the approach could generate integer compromise optimal solutions.  

  20. Gang Membership and Pathways to Maladaptive Parenting.

    Science.gov (United States)

    Augustyn, Megan Bears; Thornberry, Terence P; Krohn, Marvin D

    2014-06-01

    A limited amount of research examines the short-term consequences of gang membership. Rarer, though, is the examination of more distal consequences of gang membership. This is unfortunate because it understates the true detrimental effect of gang membership across the life course, as well as the effects it may have on children of former gang members. Using data from the Rochester Youth Development Study, this work investigates the impact of gang membership in adolescence (ages 12-18) on a particularly problematic style of parenting, child maltreatment. Using discrete time survival analysis, this study finds that gang membership increases the likelihood of child maltreatment and this relationship is mediated by the more proximal outcomes of gang membership during adolescence, precocious transitions to adulthood.

  1. Enhancing Fatigue Performance of Sandwich Composites with Nanophased Core

    Directory of Open Access Journals (Sweden)

    S. Zainuddin

    2010-01-01

    Full Text Available We report fatigue performance of sandwich composites with nanophased core under shear load. Nanophased core was made from polyurethane foam dispersed with carbon nanofiber (CNF. CNFs were dispersed into part-A of liquid polyurethane through a sonication process and the loading of nanoparticles was 1.0 wt%. After dispersion, part-A was mixed with part-B, cast into a mold, and allowed to cure. Nanophased foam was then used to fabricate sandwich composites. Static shear tests revealed that strength and modulus of nanophased foams were 33% and 19% higher than those of unreinforced (neat foams. Next, shear fatigue tests were conducted at a frequency of 3 Hz and stress ratio (R of 0.1. S-N curves were generated and fatigue performances were compared. Number of cycles to failure for nanophased sandwich was significantly higher than that of the neat ones. For example, at 57% of ultimate shear strength, nanophased sandwich would survive 400,000 cycles more than its neat counterpart. SEM micrographs indicated stronger cell structures with nanophased foams. These stronger cells strengthened the sub-interface zones underneath the actual core-skin interface. High toughness of the sub-interface layer delayed initiation of fatigue cracks and thereby increased the fatigue life of nanophased sandwich composites.

  2. A comparison of FRP-sandwich penetrating impact test methods

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrand, M. [VTT Manufacturing Technology, Espoo (Finland). Maritime and Mechanical Engineering

    1996-12-31

    The main objective of this project is to identify the test methods which provide useful results for the different types of penetrating impacts occurring in sandwich structures. A series of penetrating impact tests on FRP-sandwich panels is performed using three different test methods and the results of the test methods are compared. The test methods used are the standardised method ISO 6603 and two non-standardised methods. The first non-standardised method uses a pyramid-shaped impactor instead of the cylindrical impactor used in the ISO 6603 method. In the second non-standardised method, the impact test is performed quasistatically using a cylindrical impactor. Possible stages of failure occurring in FRP-sandwich during a penetrating impact are illustrated. A comprehensive test method should be able to provoke various failure modes, as observed in impact failures of actual sandwich structures. The results obtained with the three test methods lead to a different ranking in impact strength of the panels. Hence, impact test results obtained with different test methods are not even qualitatively comparable. The pyramid-shaped impactor is able to generate clearly more failure modes than the cylindrical impactor in the ISO 6603 method. Therefore, it is considered to be of more practical value for determining the impact strength of PRP-sandwich structures. (orig.) (15 refs.)

  3. Structural and failure mechanics of sandwich composites

    CERN Document Server

    Carlsson, LA; Carlsson, Leif A

    2011-01-01

    Focusing on important deformation and failure modes of sandwich structures, this volume describes the mechanics behind fracture processes. The text also reviews test methods developed for the cr, structural integrity, and failure mechanisms of sandwich structures.

  4. Refugees, nationalism, and political membership

    Directory of Open Access Journals (Sweden)

    Signe Larsen

    2012-09-01

    Full Text Available This essay aims to understand how refugees present a problem for liberal nation-states. The point of departure is Arendt’s The Origins of Totalitarianism where she argues that the continual existence of refugees within liberal nation-states threatens to break down the principle of equality before the law thereby enabling the rise of police-states and totalitarianism. In light of this diagnosis, three of Arendt’s philosophical heirs—Giorgio Agamben, Seyla Benhabib and Peg Birmingham—argue that it is necessary to think political membership in different and broader terms than national citizenship if we are to avoid a new rise of totalitarianism.

  5. Technology sandwich panels with mineral wool insulation

    OpenAIRE

    Tyulenev M.; Burtzeva M.; Mednikova E.

    2016-01-01

    Sandwich panel — self–supporting structure consisting of metal cladding and thermal insulation core. As a heat–insulating core used mineral wool, foamed plastics. Production of sandwich panels with insulation mineral wool performed on modular lines for the production of aggregate or conveyer scheme. Sandwich panels are used as load–bearing elements of the facades, as well as a roof covering.

  6. 12 CFR 323.6 - Professional association membership; competency.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Professional association membership; competency... OF GENERAL POLICY APPRAISALS § 323.6 Professional association membership; competency. (a) Membership... membership or lack of membership in any particular appraisal organization. (b) Competency. All staff and...

  7. Dielectrophoretic behaviours of microdroplet sandwiched between LN substrates.

    Science.gov (United States)

    Chen, Lipin; Li, Shaobei; Fan, Bolin; Yan, Wenbo; Wang, Donghui; Shi, Lihong; Chen, Hongjian; Ban, Dechao; Sun, Shihao

    2016-07-07

    We demonstrate a sandwich configuration for microfluidic manipulation in LiNbO3 platform based on photovoltaic effect, and the behaviours of dielectric microdroplet under this sandwich configuration are investigated. It is found that the microdroplet can generate in the form of liquid bridge inside the LiNbO3-based sandwich structure under the governing dielectrophoretic force, and the dynamic process of microdroplet generation highly depends on the substrate combinations. Dynamic features found for different combinations are explained by the different electrostatic field distribution basing on the finite-element simulation results. Moreover, the electrostatic field required by the microdroplet generation is estimated through meniscus evolution and it is found in good agreement with the simulated electrostatic field inside the sandwich gap. Several kinds of microdroplet manipulations are attempted in this work. We suggest that the local dielectrophoretic force acting on the microdroplet depends on the distribution of the accumulated irradiation dosage. Without using any additional pumping or jetting actuator, the microdroplet can be step-moved, deformed or patterned by the inconsecutive dot-irradiation scheme, as well as elastically stretched out and back or smoothly guided in a designed pass by the consecutive line-irradiation scheme.

  8. Dielectrophoretic behaviours of microdroplet sandwiched between LN substrates

    Science.gov (United States)

    Chen, Lipin; Li, Shaobei; Fan, Bolin; Yan, Wenbo; Wang, Donghui; Shi, Lihong; Chen, Hongjian; Ban, Dechao; Sun, Shihao

    2016-07-01

    We demonstrate a sandwich configuration for microfluidic manipulation in LiNbO3 platform based on photovoltaic effect, and the behaviours of dielectric microdroplet under this sandwich configuration are investigated. It is found that the microdroplet can generate in the form of liquid bridge inside the LiNbO3-based sandwich structure under the governing dielectrophoretic force, and the dynamic process of microdroplet generation highly depends on the substrate combinations. Dynamic features found for different combinations are explained by the different electrostatic field distribution basing on the finite-element simulation results. Moreover, the electrostatic field required by the microdroplet generation is estimated through meniscus evolution and it is found in good agreement with the simulated electrostatic field inside the sandwich gap. Several kinds of microdroplet manipulations are attempted in this work. We suggest that the local dielectrophoretic force acting on the microdroplet depends on the distribution of the accumulated irradiation dosage. Without using any additional pumping or jetting actuator, the microdroplet can be step-moved, deformed or patterned by the inconsecutive dot-irradiation scheme, as well as elastically stretched out and back or smoothly guided in a designed pass by the consecutive line-irradiation scheme.

  9. Wire and Packing Tape Sandwiches

    Science.gov (United States)

    Rabinowitz, Sandy

    2009-01-01

    In this article, the author describes how students can combine craft wire with clear packing tape to create a two-dimensional design that can be bent and twisted to create a three-dimensional form. Students sandwich wire designs between two layers of tape. (Contains 1 online resource.)

  10. Thermal-Diode Sandwich Panel

    Science.gov (United States)

    Basiulis, A.

    1986-01-01

    Thermal diode sandwich panel transfers heat in one direction, but when heat load reversed, switches off and acts as thermal insulator. Proposed to control temperature in spacecraft and in supersonic missiles to protect internal electronics. In combination with conventional heat pipes, used in solar panels and other heat-sensitive systems.

  11. High temperature structural sandwich panels

    Science.gov (United States)

    Papakonstantinou, Christos G.

    High strength composites are being used for making lightweight structural panels that are being employed in aerospace, naval and automotive structures. Recently, there is renewed interest in use of these panels. The major problem of most commercial available sandwich panels is the fire resistance. A recently developed inorganic matrix is investigated for use in cases where fire and high temperature resistance are necessary. The focus of this dissertation is the development of a fireproof composite structural system. Sandwich panels made with polysialate matrices have an excellent potential for use in applications where exposure to high temperatures or fire is a concern. Commercial available sandwich panels will soften and lose nearly all of their compressive strength temperatures lower than 400°C. This dissertation consists of the state of the art, the experimental investigation and the analytical modeling. The state of the art covers the performance of existing high temperature composites, sandwich panels and reinforced concrete beams strengthened with Fiber Reinforced Polymers (FRP). The experimental part consists of four major components: (i) Development of a fireproof syntactic foam with maximum specific strength, (ii) Development of a lightweight syntactic foam based on polystyrene spheres, (iii) Development of the composite system for the skins. The variables are the skin thickness, modulus of elasticity of skin and high temperature resistance, and (iv) Experimental evaluation of the flexural behavior of sandwich panels. Analytical modeling consists of a model for the flexural behavior of lightweight sandwich panels, and a model for deflection calculations of reinforced concrete beams strengthened with FRP subjected to fatigue loading. The experimental and analytical results show that sandwich panels made with polysialate matrices and ceramic spheres do not lose their load bearing capability during severe fire exposure, where temperatures reach several

  12. 12 CFR 725.4 - Agent membership.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Agent membership. 725.4 Section 725.4 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS NATIONAL CREDIT UNION ADMINISTRATION CENTRAL LIQUIDITY FACILITY § 725.4 Agent membership. (a) A central credit union or a group...

  13. 12 CFR 725.3 - Regular membership.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Regular membership. 725.3 Section 725.3 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS NATIONAL CREDIT UNION ADMINISTRATION CENTRAL LIQUIDITY FACILITY § 725.3 Regular membership. (a) A natural person...

  14. 10 CFR 745.107 - IRB membership.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false IRB membership. 745.107 Section 745.107 Energy DEPARTMENT OF ENERGY PROTECTION OF HUMAN SUBJECTS § 745.107 IRB membership. (a) Each IRB shall have at least five members, with varying backgrounds to promote complete and adequate review of research...

  15. Constructive membership testing in black-box classical groups

    CERN Document Server

    Ambrose, Sophie; Praeger, Cheryl E; Schneider, Csaba

    2010-01-01

    The research described in this note aims at solving the constructive membership problem for the class of quasisimple classical groups. Our algorithms are developed in the black-box group model; that is, they do not require specific characteristics of the representations in which the input groups are given. The elements of a black-box group are represented, not necessarily uniquely, as bit strings of uniform length. We assume the existence of oracles to compute the product of two elements, the inverse of an element, and to test if two strings represent the same element. Solving the constructive membership problem for a black-box group $G$ requires to write every element of $G$ as a word in a given generating set. In practice we write the elements of $G$ as straight-line programs (SLPs) which can be viewed as a compact way of writing words.

  16. Damage Tolerance of Sandwich Plates With Debonded Face Sheets

    Science.gov (United States)

    Sankar, Bhavani V.

    2001-01-01

    A nonlinear finite element analysis was performed to simulate axial compression of sandwich beams with debonded face sheets. The load - end-shortening diagrams were generated for a variety of specimens used in a previous experimental study. The energy release rate at the crack tip was computed using the J-integral, and plotted as a function of the load. A detailed stress analysis was performed and the critical stresses in the face sheet and the core were computed. The core was also modeled as an isotropic elastic-perfectly plastic material and a nonlinear post buckling analysis was performed. A Graeco-Latin factorial plan was used to study the effects of debond length, face sheet and core thicknesses, and core density on the load carrying capacity of the sandwich composite. It has been found that a linear buckling analysis is inadequate in determining the maximum load a debonded sandwich beam can carry. A nonlinear post-buckling analysis combined with an elastoplastic model of the core is required to predict the compression behavior of debonded sandwich beams.

  17. 10 YEARS AFTER NATO MEMBERSHIP

    DEFF Research Database (Denmark)

    ”10 years after NATO Membership. An Anniversary in the Shadow of a Crisis”, indeholder artikler fra politiske aktører, diplomater og forskere, der alle bidrog til til konferencen af samme navn, hvor den 10-året for baltisk medlemskab af NATO var omdrejningspunktet. Udover den danske...... forsvarsminister, er den estiske og litauiske forsvarsminister og NATO’s vicegeneralsekretær blandt bidragyderne. Konferencens formål var at fejre, inddrage og diskutere 10 års forsvarspolitisk NATO-samarbejde i Østersøområdet. Den internationale udvikling i Europa betød at konferencens dagsorden i stedet for kom...... billede af hvordan den russiske aggression på Krimhalvøen blev italesat af de repræsenterede landes Forsvarsministre samt fra hovedkvarteret i NATO. Konferencen blev afholdt tidligere i år i København, og var et resultat af et tæt samarbejde mellem Forsvarsakademiet, Forsvarsministeriet og ambassadørerne...

  18. 75 FR 69642 - Membership of the Performance Review Board (PRB)

    Science.gov (United States)

    2010-11-15

    ... Office of the Secretary Membership of the Performance Review Board (PRB) AGENCY: Department of Defense, Defense Threat Reduction Agency (DTRA). ACTION: Notice of PRB membership. SUMMARY: This notice announces the appointment of DTRA's PRB membership. The publication of the PRB membership is required by 5...

  19. 12 CFR 564.6 - Professional association membership; competency.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Professional association membership; competency... APPRAISALS § 564.6 Professional association membership; competency. (a) Membership in appraisal organizations... membership in any particular appraisal organization. (b) Competency. All staff and fee appraisers...

  20. 12 CFR 34.46 - Professional association membership; competency.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Professional association membership; competency... ESTATE LENDING AND APPRAISALS Appraisals § 34.46 Professional association membership; competency. (a... membership or lack of membership in any particular appraisal organization. (b) Competency. All staff and...

  1. 12 CFR 722.6 - Professional association membership; competency.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Professional association membership; competency... CREDIT UNIONS APPRAISALS § 722.6 Professional association membership; competency. (a) Membership in... membership in any particular appraisal organization. (b) Competency. All staff and fee appraisers...

  2. Combined compressive and shear buckling analysis of hypersonic aircraft sandwich panels

    Science.gov (United States)

    Ko, William L.; Jackson, Raymond H.

    1992-01-01

    The combined-load (compression and shear) buckling equations were established for orthotropic sandwich panels by using the Rayleigh-Ritz method to minimize the panel total potential energy. The resulting combined-load buckling equations were used to generate buckling interaction curves for super-plastically-formed/diffusion-bonded titanium truss-core sandwich panels and titanium honeycomb-core sandwich panels having the same specific weight. The relative combined-load buckling strengths of these two types of sandwich panels are compared with consideration of their sandwich orientations. For square and nearly square panels of both types, the combined load always induces symmetric buckling. As the panel aspect ratios increase, antisymmetric buckling will show up when the loading is shear-dominated combined loading. The square panel (either type) has the highest combined buckling strength, but the combined load buckling strength drops sharply as the panel aspect ratio increases. For square panels, the truss-core sandwich panel has higher compression-dominated load buckling strength. However, for shear dominated loading, the square honeycomb-core sandwich panel has higher shear-dominated combined load buckling strength.

  3. Combined compressive and shear buckling analysis of hypersonic aircraft structural sandwich panels

    Science.gov (United States)

    Ko, William L.; Jackson, Raymond H.

    1991-01-01

    The combined-load (compression and shear) buckling equations were established for orthotropic sandwich panels by using the Rayleigh-Ritz method to minimize the panel total potential energy. The resulting combined-load buckling equations were used to generate buckling interaction curves for super-plastically-formed/diffusion-bonded titanium truss-core sandwich panels and titanium honeycomb-core sandwich panels having the same specific weight. The relative combined-load buckling strengths of these two types of sandwich panels are compared with consideration of their sandwich orientations. For square and nearly square panels of both types, the combined load always induces symmetric buckling. As the panel aspect ratios increase, antisymmetric buckling will show up when the loading is shear-dominated combined loading. The square panel (either type) has the highest combined buckling strength, but the combined load buckling strength drops sharply as the panel aspect ratio increases. For square panels, the truss-core sandwich panel has higher compression-dominated combined load buckling strength. However, for shear dominated loading, the square honeycomb-core sandwich panel has higher shear-dominated combined load buckling strength.

  4. Sandwiched R\\'enyi Convergence for Quantum Evolutions

    OpenAIRE

    Müller-Hermes, Alexander; Franca, Daniel Stilck

    2016-01-01

    We study the speed of convergence of a primitive quantum time evolution towards its fixed point in the distance of sandwiched R\\'enyi divergences. For each of these distance measures the convergence is typically exponentially fast and the best exponent is given by a constant (similar to a logarithmic Sobolev constant) depending only on the generator of the time evolution. We establish relations between these constants and the logarithmic Sobolev constants as well as the spectral gap. An impor...

  5. Composite Sandwich Technologies Lighten Components

    Science.gov (United States)

    2010-01-01

    Leveraging its private resources with several Small Business Innovation Research (SBIR) contracts with both NASA and the U.S. Department of Defense, WebCore Technologies LLC, of Miamisburg, Ohio, developed a fiber-reinforced foam sandwich panel it calls TYCOR that can be used for a wide variety of industrial and consumer applications. Testing at Glenn Research Center?s Ballistic Impact Facility demonstrated that the technology was able to exhibit excellent damage localization and stiffness during impact. The patented and trademarked material has found use in many demanding applications, including marine, ground transportation, mobile shelters, bridges, and most notably, wind turbines.

  6. Standard Terminology of Structural Sandwich Constructions

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This terminology covers terms necessary for a basic uniform understanding and usage of the language peculiar to structural sandwich constructions. The simplest structural sandwich is a three layered construction formed by bonding a thin layer (facing) to each side of a thick layer (core).

  7. Development and Evaluation of Stitched Sandwich Panels

    Science.gov (United States)

    Stanley, Larry E.; Adams, Daniel O.; Reeder, James R. (Technical Monitor)

    2001-01-01

    This study explored the feasibility and potential benefits provided by the addition of through-the-thickness reinforcement to sandwich structures. Through-the-thickness stitching is proposed to increase the interlaminar strength and damage tolerance of composite sandwich structures. A low-cost, out-of-autoclave processing method was developed to produce composite sandwich panels with carbon fiber face sheets, a closed-cell foam core, and through-the-thickness Kevlar stitching. The sandwich panels were stitched in a dry preform state, vacuum bagged, and infiltrated using Vacuum Assisted Resin Transfer Molding (VARTM) processing. For comparison purposes, unstitched sandwich panels were produced using the same materials and manufacturing methodology. Test panels were produced initially at the University of Utah and later at NASA Langley Research Center. Four types of mechanical tests were performed: flexural testing, flatwise tensile testing, core shear testing, and edgewise compression testing. Drop-weight impact testing followed by specimen sectioning was performed to characterize the damage resistance of stitched sandwich panels. Compression after impact (CAI) testing was performed to evaluate the damage tolerance of the sandwich panels. Results show significant increases in the flexural stiffness and strength, out-of-plane tensile strength, core shear strength, edgewise compression strength, and compression-after-impact strength of stitched sandwich structures.

  8. Detection of Penicillinase in Milk by Sandwich ELISA Based Polyclonal and Monoclonal Antibody.

    Science.gov (United States)

    Zhao, Yinli; Li, Guoxi

    2016-01-01

    A sandwich ELISA has been developed using polyclonal and monoclonal antibody for the determination of penicillinase in milk. For this purpose, specific polyclonal and monoclonal antibodies against penicillinase were generated and characterized. Using penicillinase standards prepared from 1-128 ng/mL, the method indicated that the detection limit of the sandwich ELISA, as measured in an ELISA plate reader, was as low as 0.86 ng/mL of penicillinase. For determine the accuracy, raw milk containing 2, 8, 32, and 64 ng/mL of penicillinase were tested by sandwich ELISA. Recoveries were from 93-97.5%, and the coefficient of variation [CV (%)] were from 5.55-8.38%. For interassay reproducibility, recoveries were from 89.5-95.1%, the coefficient of variation [CV (%)] were from 5.26-9.58%. This sandwich ELISA provides a useful screening method for quantitative detection of penicillinase in milk.

  9. Other-Initiated Repair and Membership Categorization

    DEFF Research Database (Denmark)

    Egbert, Maria

    2004-01-01

    In continuation of recent discussions in JoP and elsewhere concerning the aptness of conversation analysis (‘‘CA’’) as a research methodology for ‘‘intercultural’’ interaction, this CA-study shows some procedures by which interactants overtly or covertly orient to regional or linguistic category...... membership where apparent trouble in hearing or understanding the talk are addressed (‘‘other- initiated repair’’ [Language 54 (2) (1977) 361]). These practices of membership categorizing are inferred from different kinds of structural elaborateness beyond the basic two-part repair sequence. CA is shown...... to provide analytic tools which are highly suitable to detecting and describing practices of membership categorizing along regional or linguistic lines both in so-called ‘‘native/native’’ and ‘‘native/nonnative’’ interaction....

  10. A Community Membership Life Cycle Model

    CERN Document Server

    Sonnenbichler, Andreas C

    2010-01-01

    Web 2.0 is transforming the internet: Information consumers become information producers and consumers at the same time. In virtual places like Facebook, Youtube, discussion boards and weblogs diversificated topics, groups and issues are propagated and discussed. Today an internet user is a member of lots of communities at different virtual places. "Real life" group membership and group behavior has been analyzed in science intensively in the last decades. Most interestingly, to our knowledge, user roles and behavior have not been adapted to the modern internet. In this work, we give a short overview of traditional community roles. We adapt those models and apply them to virtual online communities. We suggest a community membership life cycle model describing roles a user can take during his membership in a community. Our model is systematic and generic; it can be adapted to concrete communities in the web. The knowledge of a community's life cycle allows influencing the group structure: Stage transitions can...

  11. Membership Functions for Fuzzy Focal Elements

    Directory of Open Access Journals (Sweden)

    Porębski Sebastian

    2016-09-01

    Full Text Available The paper presents a study on data-driven diagnostic rules, which are easy to interpret by human experts. To this end, the Dempster-Shafer theory extended for fuzzy focal elements is used. Premises of the rules (fuzzy focal elements are provided by membership functions which shapes are changing according to input symptoms. The main aim of the present study is to evaluate common membership function shapes and to introduce a rule elimination algorithm. Proposed methods are first illustrated with the popular Iris data set. Next experiments with five medical benchmark databases are performed. Results of the experiments show that various membership function shapes provide different inference efficiency but the extracted rule sets are close to each other. Thus indications for determining rules with possible heuristic interpretation can be formulated.

  12. New "sandwich" structures conformed from three dimensional

    Directory of Open Access Journals (Sweden)

    Alba, Juan J.

    1996-03-01

    Full Text Available Poor interlaminar properties as well as poor-skin-to-core adhesion properties are very often the common existing problems we find when designing with "sandwich" structures. A new type of 3D-fabric "sandwich" structure is being developed in order to avoid these problems. Although the manufacturing process is very simple, a very complex "sandwich" structure is obtained as a result of the complexity of the 3D-fabric used. This 3D-fabric is a 3D woven glass fabric produced on velvet weaving machines with glass yarns. It is an integrally woven "sandwich" laminate for all kinds of composite products. The strength of the vertical fibers makes, that also after impregnation with a resin matrix, the "sandwich" structure is maintained. The result is a laminate with high strength and stiffness and low weight. On each side of this "sandwich" laminate additional reinforcement materials can be laminated and a synthetic foam can be injected in the hollow structure. This will allow to establish the mechanical properties of a finished product.

    Las pobres propiedades, tanto interlaminares como de adhesión entre piel y núcleo, constituyen uno de los grandes problemas cuando se diseñan estructuras utilizando paneles tipo "sandwich". Un nuevo tipo de panel "sandwich", configurado a partir de tejidos tridimensionales, está siendo desarrollado en la actualidad con el objetivo de eliminar esos problemas. Aunque el proceso de fabricación es muy simple, el panel "sandwich" obtenido es de estructura compleja, como resultado de la complejidad del tejido tridimensional utilizado. Este tejido tridimensional (3D es un tejido de fibra de vidrio producido en máquinas de tejer especializadas. La resistencia de las fibras verticales hace que, después de la impregnación con una resina, se mantenga la configuración tipo "sandwich". El resultado es un laminado de alta resistencia, gran rigidez y bajo peso. Sobre cada uno de los lados del panel "sandwich" se pueden

  13. New "sandwich" structures conformed from three dimensional

    OpenAIRE

    1996-01-01

    Poor interlaminar properties as well as poor-skin-to-core adhesion properties are very often the common existing problems we find when designing with "sandwich" structures. A new type of 3D-fabric "sandwich" structure is being developed in order to avoid these problems. Although the manufacturing process is very simple, a very complex "sandwich" structure is obtained as a result of the complexity of the 3D-fabric used. This 3D-fabric is a 3D woven glass fabric produced on velvet weaving machi...

  14. Systematic selection of modified aptamer pairs for diagnostic sandwich assays.

    Science.gov (United States)

    Ochsner, Urs A; Green, Louis S; Gold, Larry; Janjic, Nebojsa

    2014-01-01

    Protein diagnostic applications typically require pairs of analyte-specific reagents for capture and detection. We developed methods for the systematic isolation of slow off-rate modified aptamer (SOMAmer) reagents that bind to different epitopes and allow efficient pair-wise screening of multiple ligands. SOMAmers were generated via a second systematic evolution of ligands by exponential enrichment (SELEX), using complexes of target proteins with a primary, non-amplifiable SOMAmer and employing different modified nucleotides (e.g., naphthylmethyl- or tryptaminocarbonyl-dU) to favor alternate binding epitopes. Non-competing binding of primary and secondary SOMAmers was tested in radiolabel competition and sandwich binding assays. Multiplexed high-throughput screening for sandwich pairs utilized the Luminex platform, with primary SOMAmers as capture agents attached to different types of LumAvidin beads, which were then pooled for testing the secondary SOMAmers individually as detection agents. Functional SOMAmer pairs were obtained for Clostridium difficile binary toxin (CdtA) and for a panel of human proteins (ANGPT2, TSP2, CRDL1, MATN2, GPVI, C7, PLG) that had been previously identified as promising markers for cardiovascular risk. The equilibrium dissociation constants (Kd values) ranged from 0.02-2.7 nM, and the detection limits were in the low picomolar range for these proteins in SOMAmer sandwich assays. These results indicate that SOMAmer pairs hold promise for the development of rapid tests or specific diagnostic panels.

  15. Buckling driven debonding in sandwich columns

    DEFF Research Database (Denmark)

    Østergaard, Rasmus Christian

    2008-01-01

    A compression loaded sandwich column that contains a debond is analyzed using a geometrically non-linear finite element model. The model includes a cohesive zone along one face sheet/core interface whereby the debond can extend by interface crack growth. Two geometrical imperfections are introduced......; a global imperfection of the sandwich column axis and a local imperfection of the debonded face sheet axis. The model predicts the sandwich column to be very sensitive to the initial debond length and the local face sheet imperfection. The study shows that the sensitivity to the face sheet imperfection...... results from two mechanisms: (a) interaction of local debond buckling and global buckling and (b) the development of a damaged zone at the debond crack tip. Based on the pronounced imperfection sensitivity, the author predicts that an experimental measurement of the strength of sandwich structures may...

  16. Local slamming impact of sandwich composite hulls

    National Research Council Canada - National Science Library

    Qin, Z; Batra, R.C

    2009-01-01

    We develop a hydroelastic model based on a {3,2}-order sandwich composite panel theory and Wagner's water impact theory for investigating the fluid-structure interaction during the slamming process...

  17. 16 CFR 1018.16 - Membership selection.

    Science.gov (United States)

    2010-01-01

    ....16 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION GENERAL ADVISORY COMMITTEE MANAGEMENT... volunteer, that bear any relationship to the subject area of product safety or to membership on the advisory... qualified, staff members of the Commission, including the Advisory Committee Management Officer. (d)...

  18. 77 FR 66824 - Performance Review Board Membership

    Science.gov (United States)

    2012-11-07

    ... review and evaluate the initial appraisal of senior executives' performance by supervisors and make... Evaluation Command. 7. Ms. Sue A. Engelhardt, Director of Human Resources, United States Army Corps of... Department of the Army Performance Review Board Membership AGENCY: Department of the Army, DoD....

  19. 14 CFR 1230.107 - IRB membership.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false IRB membership. 1230.107 Section 1230.107 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PROTECTION OF HUMAN SUBJECTS § 1230.107..., including consideration of race, gender, and cultural backgrounds and sensitivity to such issues...

  20. Gym Membership Makes Your Heart Fitter, Too

    Science.gov (United States)

    ... Site Map FAQs Customer Support Health Topics Drugs & Supplements Videos & Tools Español You Are Here: Home → Latest Health News → Article URL of this page: https://medlineplus.gov/news/fullstory_163490.html Gym Membership Makes Your Heart Fitter, Too Study found ...

  1. 45 CFR 1700.3 - Membership.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Membership. 1700.3 Section 1700.3 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE..., the Director of the Institute of Museum and Library Services (who serves as an ex officio,...

  2. 16 CFR 1028.107 - IRB membership.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false IRB membership. 1028.107 Section 1028.107 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION GENERAL PROTECTION OF HUMAN SUBJECTS § 1028.107 IRB..., to promote respect for its advice and counsel in safeguarding the rights and welfare of human...

  3. 45 CFR 690.107 - IRB membership.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false IRB membership. 690.107 Section 690.107 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION PROTECTION OF HUMAN... to such issues as community attitudes, to promote respect for its advice and counsel in...

  4. 45 CFR 46.107 - IRB membership.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false IRB membership. 46.107 Section 46.107 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PROTECTION OF HUMAN SUBJECTS Basic..., gender, and cultural backgrounds and sensitivity to such issues as community attitudes, to...

  5. 75 FR 71417 - Manufacturing Council Membership

    Science.gov (United States)

    2010-11-23

    ... International Trade Administration Manufacturing Council Membership AGENCY: International Trade Administration... Manufacturing Council. SUMMARY: The Department of Commerce is currently seeking applications to fill one vacant position on the Manufacturing Council (Council). The purpose of the Council is to advise the Secretary of...

  6. On the Milnor fibers of sandwiched singularities

    OpenAIRE

    Nemethi, Andras; Popescu-Pampu, Patrick

    2009-01-01

    The sandwiched surface singularities are those rational surface singularities which dominate birationally smooth surface singularities. de Jong and van Straten showed that one can reduce the study of the deformations of a sandwiched surface singularity to the study of deformations of a 1-dimensional object, a so-called decorated plane curve singularity. In particular, the Milnor fibers corresponding to their various smoothing components may be reconstructed up to diffeomorphisms from those de...

  7. On the use of robust estimators for standard errors in the presence of clustering when clustering membership is misspecified.

    Science.gov (United States)

    Desai, Manisha; Bryson, Susan W; Robinson, Thomas

    2013-03-01

    This paper examines the implications of using robust estimators (REs) of standard errors in the presence of clustering when cluster membership is unclear as may commonly occur in clustered randomized trials. For example, in such trials, cluster membership may not be recorded for one or more treatment arms and/or cluster membership may be dynamic. When clusters are well defined, REs have properties that are robust to misspecification of the correlation structure. To examine whether results were sensitive to assumptions about the clustering membership, we conducted simulation studies for a two-arm clinical trial, where the number of clusters, the intracluster correlation (ICC), and the sample size varied. REs of standard errors that incorrectly assumed clustering of data that were truly independent yielded type I error rates of up to 40%. Partial and complete misspecifications of membership (where some and no knowledge of true membership were incorporated into assumptions) for data generated from a large number of clusters (50) with a moderate ICC (0.20) yielded type I error rates that ranged from 7.2% to 9.1% and 10.5% to 45.6%, respectively; incorrectly assuming independence gave a type I error rate of 10.5%. REs of standard errors can be useful when the ICC and knowledge of cluster membership are high. When the ICC is weak, a number of factors must be considered. Our findings suggest guidelines for making sensible analytic choices in the presence of clustering.

  8. On the Cell Probe Complexity of Membership and Perfect Hashing

    DEFF Research Database (Denmark)

    Pagh, Rasmus

    2001-01-01

    We study two fundamental static data structure problems, membership and perfect hashing, in Yao's cell probe model. The first space and bit probe optimal worst case upper bound is given for the membership problem. We also give a new efficient membership scheme where the query algorithm makes just...

  9. Senior membership programs should be cross-marketing tools.

    Science.gov (United States)

    Johnsson, J

    1990-07-05

    Senior membership programs, a long-time staple in marketing strategies, are undergoing changes. Hospital executives say that to be successful, membership programs must offer more than just free meals and travelogs. Most thriving membership programs have a strong clinical orientation.

  10. Devices, systems, and methods for conducting sandwich assays using sedimentation

    Energy Technology Data Exchange (ETDEWEB)

    Schaff, Ulrich Y; Sommer, Gregory J; Singh, Anup K; Hatch, Anson V

    2015-02-03

    Embodiments of the present invention are directed toward devices, systems, and method for conducting sandwich assays using sedimentation. In one example, a method includes generating complexes on a plurality of beads in a fluid sample, individual ones of the complexes comprising a capture agent, a target analyte, and a labeling agent. The plurality of beads including the complexes may be transported through a density media, wherein the density media has a density lower than a density of the beads and higher than a density of the fluid sample, and wherein the transporting occurs, at least in part, by sedimentation. Signal may be detected from the labeling agents of the complexes.

  11. Energy Dissipation in Sandwich Structures During Axial Compression

    DEFF Research Database (Denmark)

    Urban, Jesper

    2002-01-01

    The purpose of this paper is to investigate the energy dissipation in sandwich structures during axial crushing. Axial crushing tests on six sandwich elements are described. The sandwich elements consist of a polyurethane core and E-glass/Polyester skin. The elements compare to full-scale structu......The purpose of this paper is to investigate the energy dissipation in sandwich structures during axial crushing. Axial crushing tests on six sandwich elements are described. The sandwich elements consist of a polyurethane core and E-glass/Polyester skin. The elements compare to full...

  12. 50 years of membership in AGU recognized

    Science.gov (United States)

    Recently seven members who joined the Union in 1941 received their gold pins in recognition of 50 years of membership in the Union. They join the distinguished ranks of the other 50-year members, all of whom are listed below by the year they joined. 1941 Max Bookman, Desmond F. Glynn, William F. Guyton, Kenneth E. Lohman, Charles Miron, Russell W. Revell, and Wilbur T. Stuart

  13. Group Membership Based Authorization to CADC Resources

    Science.gov (United States)

    Damian, A.; Dowler, P.; Gaudet, S.; Hill, N.

    2012-09-01

    The Group Membership Service (GMS), implemented at the Canadian Astronomy Data Centre (CADC), is a prototype of what could eventually be an IVOA standard for a distributed and interoperable group membership protocol. Group membership is the core authorization concept that enables teamwork and collaboration amongst astronomers accessing distributed resources and services. The service integrates and complements other access control related IVOA standards such as single-sign-on (SSO) using X.509 proxy certificates and the Credential Delegation Protocol (CDP). The GMS has been used at CADC for several years now, initially as a subsystem and then as a stand-alone Web service. It is part of the authorization mechanism for controlling the access to restricted Web resources as well as the VOSpace service hosted by the CADC. We present the role that GMS plays within the access control system at the CADC, including the functionality of the service and how the different CADC services make use of it to assert user authorization to resources. We also describe the main advantages and challenges of using the service as well as future work to increase its robustness and functionality.

  14. Factors affecting membership in specialty nursing organizations.

    Science.gov (United States)

    White, Mary Joe; Olson, Rhonda S

    2004-01-01

    A discouraging trend in many specialty nursing organizations is the stagnant or declining membership. The research committee of the Southeast Texas Chapter of the Association of Rehabilitation Nurses (ARN) collected data and studied this trend to determine what changes would be necessary to increase membership. Using Herzberg's motivational theory as a framework, a review of the literature was initiated. There were few current studies on this issue, but relevant information was found about nursing's emerging workforce, as well as implications of the growth of magnet hospitals, which affect whether nurses join specialty nursing organizations. A multifaceted data-collection approach using convenience samples was designed. First, relevant literature was reviewed. Second, a survey was sent by e-mail to other ARN chapters. Third, a telephone survey on other specialty organizations in the geographic region was completed. Finally, members of the local ARN chapter and four other specialty organizations, as well staff nurses in the geographic area, were given questionnaires to complete. Descriptive statistics and cross tabulations were used to determine why nurses do and do not join specialty organizations (N = 81). The most frequent reasons for joining an organization were to increase knowledge, benefit professionally, network, and earn continuing education units. Reasons for choosing not to participate were family responsibilities, lack of information about these organizations, and lack of time. Ways to reverse the decline in membership are discussed.

  15. Vibro-acoustics of lightweight sandwich structures

    CERN Document Server

    Lu, Tianjian

    2014-01-01

    Vibro-Acoustics of Lightweight Sandwich Structures introduces the study of the coupled vibration and acoustic behavior of lightweight sandwich structures in response to harmonic force and sound pressure. This book focuses on the theoretical modeling and experimental investigation of lightweight sandwich structures in order to provide a predictive framework for vibro-acoustic characteristics of typical engineering structures. Furthermore, by developing solution tools, it concentrates on the influence of key systematic parameters leading to effective guidance for optimal structure design toward lightweight, high-stiffness and superior sound insulation capability. This book is intended for researchers, scientists, engineers and graduate students in mechanical engineering especially in structural mechanics, mechanics and acoustics. Fengxian Xin and Tianjian Lu both work at the School of Aerospace, Xi’an Jiaotong University.

  16. Novel 1-D Sandwich Photonic Bandgap Structure

    Institute of Scientific and Technical Information of China (English)

    庞云波; 高葆新

    2004-01-01

    A sandwich photonic bandgap (PBG) structure is a novel PBG structure whose periodic lattice is buried in the middle of a substrate. Neither drilling nor suspending the substrate is required, and the integrity of the ground plane is maintained. This paper presents several modification techniques for sandwich PBG structure fabrication. The forbidden gap can be improved by adopting the chirping technique, applying the tapering technique, enlarging the periodic elements, adjusting the location of the periodic lattice in the substrate, and using different dielectric media H-shape elements. A finite difference time domain method is applied to analyze the structures. Deep and wide stopbands can be obtained using the modified sandwich structures. Experimental measurement results agree well with the theoretical analysis.

  17. Behaviour of Metal Foam Sandwich Panels

    DEFF Research Database (Denmark)

    2011-01-01

    Sandwich panels as used in structures comprise of a foam core enclosed by thin high strength steel faces. This paper discusses currently design formulae of local buckling behaviour of such panels using the finite element method. Multiple wave finite element models were adopted to investigate...... and examine the adequacy of currently used approach for the design of sandwich panels. The paper presents brief details of the finite element model used including geometry, load pattern and boundary conditions. The selected model gives good agreement with experimental results from Pokharel and Mahendran (2003......). The study shows that currently available design formulae are conservative for stocky sandwich plate elements while being over-conservative for high slenderness. A unified design formula of local buckling behaviour applicable to the full range of slenderness is developed....

  18. Research on EM pulse protection property of plasma-microwave absorptive material-plasma sandwich structure

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A plasma-microwave absorptive material (MAM)-plasma sandwich structure is presented to protect the electronic device against high power electromagnetic pulse. The model of electromagnetic wave reflected by and transmitting through the structure is established. Based on the characteristic parameters of plasma generated by discharge and usual MAM, the electromagnetic transmissive properties of the sandwich structure are investigated by the method of finite difference in time domain. The results indicate that in a rather broad frequency range, the electromagnetic attenuations by the structure are obviously better than the sum of attenuations resulted from plasma and MAM respectively. The models and results presented are instructive for electromagnetic pulse protection.

  19. Sandwiched confinement of quantum dots in graphene matrix for efficient electron transfer and photocurrent production

    DEFF Research Database (Denmark)

    Zhu, Nan; Zheng, Kaibo; J. Karki, Khadga

    2015-01-01

    matrix via interfacial self-assembly, leading to the formation of sandwiched hybrid QD-graphene nanofilms. We have explored structural features, electron transfer kinetics and photocurrent generation capacity of such hybrid nanofilms using a wide variety of advanced techniques. Graphene nanosheets...

  20. AA, sandwich line with magnetic horn

    CERN Multimedia

    1980-01-01

    The magnetic horn, focusing the antiprotons emanating from the target, was affixed to a sandwich line through which the 150 kA pulses were supplied. Expecting to have to change from time to time the fragile horn (inner conductor only 0.7 mm thick), the assembly was designed for quick exchange. At the lower end of the sandwich line we see the connectors for the high-current cables, at the upper end the magnet horn. It has just been lifted from the V-supports which held it aligned downstream of the target. Continue with 8010293.

  1. Hyperglucagonaemia analysed by glucagon sandwich ELISA

    DEFF Research Database (Denmark)

    Albrechtsen, Nicolai Jacob Wewer; Hartmann, Bolette; Veedfald, Simon

    2014-01-01

    characterised. The specific determination of fully processed, intact glucagon requires a 'sandwich' assay employing a combination of antibodies directed against both N- and C-termini. We compared a novel assay for intact glucagon with a highly sensitive C-terminal RIA (hitherto considered specific) to determine...... the extent to which the hyperglucagonaemia measured in clinical samples was caused by authentic glucagon. METHODS: We examined the performance of three commercial glucagon 'sandwich' ELISAs. The ELISA with the best overall performance was selected to compare glucagon measurements in clinical samples...

  2. Nonlinear dynamic analysis of sandwich panels

    Science.gov (United States)

    Lush, A. M.

    1984-01-01

    Two analytical techniques applicable to large deflection dynamic response calculations for pressure loaded composite sandwich panels are demonstrated. One technique utilizes finite element modeling with a single equivalent layer representing the face sheets and core. The other technique utilizes the modal analysis computer code DEPROP which was recently modified to include transverse shear deformation in a core layer. The example problem consists of a simply supported rectangular sandwich panel. Included are comparisons of linear and nonlinear static response calculations, in addition to dynamic response calculations.

  3. OPTIMAL DESIGN OF QUADRATIC SANDWICH PLATE

    Directory of Open Access Journals (Sweden)

    TIMAR Dr. Imre

    2016-05-01

    Full Text Available In this paper, we show the optimal design of the three-layered sandwich plates. The objective function contains the material and fabrication costs. The design constraints are the maximal stresses, the deflection of plates and damping of vibrations. The unknown is the thickness of the filling foam. By the mathematical method, we define the minima of the cost function and the optimal thickness of the filling layer of foam. The active constraint is the deflection, so we calculate of the costs of the sandwich plate with the homogeneous plate.

  4. Advanced Mechanical Testing of Sandwich Materials

    DEFF Research Database (Denmark)

    Hayman, Brian; Berggreen, Christian; Jenstrup, Claus

    2008-01-01

    An advanced digital optical system has been used to measure surface strains on sandwich face and core specimens tested in a project concerned with improved criteria for designing sandwich X-joints. The face sheet specimens were of glass reinforced polyester and were tested in tension. The core...... specimens were of PVC foam and were tested in compression. The tests were performed in order to validate the use of the measurement system on these materials and to obtain material data for use in numerical simulations. While some limitations were identified, the optical system performed well and appears...

  5. Structural Response of Polyethylene Foam-Based Sandwich Panels Subjected to Edgewise Compression

    Directory of Open Access Journals (Sweden)

    Luciano Lamberti

    2013-10-01

    Full Text Available This study analyzes the mechanical behavior of low density polyethylene foam core sandwich panels subjected to edgewise compression. In order to monitor panel response to buckling, strains generated in the facesheets and overall out-of-plane deformations are measured with strain gages and projection moiré, respectively. A finite element (FE model simulating the experimental test is developed. Numerical results are compared with moiré measurements. After having been validated against experimental evidence, the FE model is parameterized, and a trade study is carried out to investigate to what extent the structural response of the panel depends on the sandwich wall construction and facesheet/core interface defects. The projection moiré set-up utilized in this research is able to capture the sudden and very localized buckling phenomena occurring under edgewise compression of foam-based sandwich panels. Results of parametric FE analyses indicate that, if the total thickness of the sandwich wall is fixed, including thicker facesheets in the laminate yields a larger deflection of the panel that becomes more sensitive to buckling. Furthermore, the mechanical response of the foam sandwich panel is found to be rather insensitive to the level of waviness of core-facesheet interfaces.

  6. Influence of residual stresses on the tensile strength of composite-metal sandwich laminates

    Science.gov (United States)

    Herakovich, C. T.; Wong, D. M.

    1977-01-01

    The tensile strength of boron-epoxy/aluminum sandwich laminates is discussed relative to the residual thermal stresses generated by curing and bonding at elevated temperatures. It is shown that the sandwich laminates investigated exhibit three dinstinct modes of failure, depending upon the fiber orientation of the composite. Sandwich laminates with moderate to high percentage of 0-deg fibers exhibit early failures initiated by edge effect; laminates with moderate to high percentage of 90-deg fibers fail according to a first-ply failure criterion; laminates with moderate to high percentages of plus or minus 45 deg plies fail at strains equal to or greater than the failure strain of the corresponding all-composite laminate.

  7. Thermo-Electro-Mechanical Analysis of a Curved Functionally Graded Piezoelectric Actuator with Sandwich Structure

    Directory of Open Access Journals (Sweden)

    Liying Jiang

    2011-12-01

    Full Text Available In this work, the problem of a curved functionally graded piezoelectric (FGP actuator with sandwich structure under electrical and thermal loads is investigated. The middle layer in the sandwich structure is functionally graded with the piezoelectric coefficient g31 varying continuously along the radial direction of the curved actuator. Based on the theory of linear piezoelectricity, analytical solutions are obtained by using Airy stress function to examine the effects of material gradient and heat conduction on the performance of the curved actuator. It is found that the material gradient and thermal load have significant influence on the electroelastic fields and the mechanical response of the curved FGP actuator. Without the sacrifice of actuation deflection, smaller internal stresses are generated by using the sandwich actuator with functionally graded piezoelectric layer instead of the conventional bimorph actuator. This work is very helpful for the design and application of curved piezoelectric actuators under thermal environment.

  8. Influence of Sandwich-Type Constrained Layer Damper Design Parameters on Damping Strength

    Directory of Open Access Journals (Sweden)

    Inaki Merideno

    2016-01-01

    Full Text Available This paper presents a theoretical study of the parameters that influence sandwich-type constrained layer damper design. Although there are different ways to reduce the noise generated by a railway wheel, most devices are based on the mechanism of increasing wheel damping. Sandwich-type constrained layer dampers can be designed so their resonance frequencies coincide with the wheel’s resonant vibration frequencies, and thus the damping effect can be concentrated within the frequency ranges of interest. However, the influence of design parameters has not yet been studied. Based on a number of numerical simulations, this paper provides recommendations for the design stages of sandwich-type constrained layer dampers.

  9. Thermo-Electro-Mechanical Analysis of a Curved Functionally Graded Piezoelectric Actuator with Sandwich Structure.

    Science.gov (United States)

    Yan, Zhi; Zaman, Mostafa; Jiang, Liying

    2011-12-12

    In this work, the problem of a curved functionally graded piezoelectric (FGP) actuator with sandwich structure under electrical and thermal loads is investigated. The middle layer in the sandwich structure is functionally graded with the piezoelectric coefficient g31 varying continuously along the radial direction of the curved actuator. Based on the theory of linear piezoelectricity, analytical solutions are obtained by using Airy stress function to examine the effects of material gradient and heat conduction on the performance of the curved actuator. It is found that the material gradient and thermal load have significant influence on the electroelastic fields and the mechanical response of the curved FGP actuator. Without the sacrifice of actuation deflection, smaller internal stresses are generated by using the sandwich actuator with functionally graded piezoelectric layer instead of the conventional bimorph actuator. This work is very helpful for the design and application of curved piezoelectric actuators under thermal environment.

  10. Plasmonic nanomesh sandwiches for ultrathin film silicon solar cells

    Science.gov (United States)

    Gao, Tongchuan; Wang, Baomin; Leu, Paul W.

    2017-02-01

    We theoretically investigate the strategy of integrating metal nanoparticles (NPs)/nanomeshes (NMs) into the top and/or bottom of crystalline silicon (c-Si) thin film solar cells for light trapping and enhanced carrier collection. C-Si thin films exhibit absorption resonances corresponding to Fabry-Pérot modes. Frontside metal NPs enhance absorption by additionally coupling light into localized surface plasmon resonances and c-Si waveguide modes, while a frontside metal NM increases absorption by coupling light into surface plasmon polaritons and c-Si waveguide modes. The frontside metal NM also functions as a flexible top electrode, which may replace conventional brittle transparent conductive oxide thin films. The backside metal NM exhibits enhanced absorption due to the coupling of light into c-Si waveguide modes and the cavity modes within the holes of metal NM. We illustrate how the optimal metal NM sandwich, consisting of NMs on both sides of a 300 nm thick c-Si with an appropriate antireflection coating (ARC), achieves a 72.9% enhancement in short-circuit current density compared with that of a 300 nm thick c-Si thin film solar cell with 100 nm thick Si3N4 ARC and 300 nm thick Ag back reflector. The current generation in the metal NM sandwich is more in the center of the thin film such that there should be less surface recombination. The uniform current generation throughout the film results in less overall recombination.

  11. Immunometric Double-Antibody Sandwich Enzyme-Linked Immunosorbent Assay.

    Science.gov (United States)

    Kohl, Thomas O; Ascoli, Carl A

    2017-06-01

    The double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) is preferentially used to determine the concentration of unknown antibody in a sample. Pure antigen is not required in this assay; however, the use of a reporter-labeled detection antibody is essential. The double-antibody sandwich ELISA is suitable for epitope mapping of different monoclonal antibodies that have been generated against a single antigen. First, plates are coated with a capture antibody specific for immunoglobulins generated by immunization of a host species. Next, the test antibody solution (e.g., serum) is incubated with the capture antibody to facilitate binding. The plates are washed to remove unbound antibody, and then antigen is added. The plates are washed again followed by the addition of an antigen-specific reporter-labeled antibody. Following incubation, unbound reporter antibody is washed off, and reporter-specific substrate is added. Reporter-mediated substrate hydrolysis is visualized and measured. The signal is proportional to the number of test antibodies present in the serum. © 2017 Cold Spring Harbor Laboratory Press.

  12. Mixed-Membership Stochastic Block-Models for Transactional Networks

    CERN Document Server

    Shafiei, Mahdi

    2010-01-01

    Transactional network data can be thought of as a list of one-to-many communications(e.g., email) between nodes in a social network. Most social network models convert this type of data into binary relations between pairs of nodes. We develop a latent mixed membership model capable of modeling richer forms of transactional network data, including relations between more than two nodes. The model can cluster nodes and predict transactions. The block-model nature of the model implies that groups can be characterized in very general ways. This flexible notion of group structure enables discovery of rich structure in transactional networks. Estimation and inference are accomplished via a variational EM algorithm. Simulations indicate that the learning algorithm can recover the correct generative model. Interesting structure is discovered in the Enron email dataset and another dataset extracted from the Reddit website. Analysis of the Reddit data is facilitated by a novel performance measure for comparing two soft ...

  13. New examples of sandwich gravitational waves and their impulsive limit

    CERN Document Server

    Podolsky, J

    1998-01-01

    Non-standard sandwich gravitational waves are constructed from the homogeneous pp vacuum solution and the motions of free test particles in the space-times are calculated explicitly. They demonstrate the caustic property of sandwich waves. By performing limits to impulsive gravitational wave it is demonstrated that the resulting particle motions are identical regardless of the ''initial'' sandwich.

  14. Non-linear analytical solutions for laterally loaded sandwich plates

    DEFF Research Database (Denmark)

    Riber, Hans Jørgen

    1997-01-01

    This work focuses on the response of orthotropic sandwich composite plates with large deflections due to high lateral loads. The results have special application to the design of ship structures. A geometrical nonlinear theory is outlined, on the basis of the classical sandwich plate theory...... of sandwich plates subjected to high lateral loading. (C) 1997 Published by Elsevier Science Ltd. All rights reserved....

  15. AA, sandwich line with magnetic horn

    CERN Document Server

    1980-01-01

    Continuation from 8010293: Finally, the sandwich line with the horn is placed on the ground, for the horn to be inspected and, if needed, exchanged for a new one. The whole procedure was trained with several members of the AA team, for quick and safe handling, and to share the radiation dose amongst them.

  16. Proof of the Thin Sandwich Conjecture

    CERN Document Server

    Bartnik, R; Bartnik, Robert; Fodor, Gyula

    1993-01-01

    We prove that the Thin Sandwich Conjecture in general relativity is valid, provided that the data $(g_{ab},\\dot g_{ab})$ satisfy certain geometric conditions. These conditions define an open set in the class of possible data, but are not generically satisfied. The implications for the ``superspace'' picture of the Einstein evolution equations are discussed.

  17. Behaviour of Metal Foam Sandwich Panels

    DEFF Research Database (Denmark)

    2011-01-01

    Sandwich panels as used in structures comprise of a foam core enclosed by thin high strength steel faces. This paper discusses currently design formulae of local buckling behaviour of such panels using the finite element method. Multiple wave finite element models were adopted to investigate...

  18. Structural detailing of openings in sandwich panels

    NARCIS (Netherlands)

    Tomà, T.; Courage, W.

    1996-01-01

    European Recommendations exist which provide calculation rules to determine the strength and stiffness of sandwich panels composed of two metal faces with a foam in between. In case of openings in such panels (e.g. for windows) an influence will appear with regard to the stiffness and loadbearing ca

  19. X-joints in composite sandwich panels

    NARCIS (Netherlands)

    Vredeveldt, A.W.; Janssen, G.Th.M.

    1998-01-01

    The small structural weight of fast large ships such as fast mono hulls or catamaran type of ships is of extreme importance to their success. One possible light weight structural solution is the sandwich panel with fibre reinforced laminates and a balsa, honeycomb or foam core. A severe obstacle for

  20. Organometallic half-sandwich iridium anticancer complexes

    NARCIS (Netherlands)

    Liu, Z.; Habtemariam, A.; Pizarro, A.M.; Fletcher, S.A.; Kisova, A.; Vrana, O.; Salassa, L.; Bruijnincx, P.C.A.|info:eu-repo/dai/nl/33799529X; Clarkson, G.J.; Brabec, V.; Sadler, Peter J.

    2011-01-01

    The low-spin 5d6 IrIII organometallic half-sandwich complexes [(η5-Cpx)Ir(XY)Cl]0/+, Cpx = Cp*, tetramethyl(phenyl)cyclopentadienyl (Cpxph), or tetramethyl(biphenyl)cyclopentadienyl (Cpxbiph), XY = 1,10-phenanthroline (4−6), 2,2′-bipyridine (7−9), ethylenediamine (10 and 11), or picolinate (12−14),

  1. Feedback Sandwiches Affect Perceptions but Not Performance

    Science.gov (United States)

    Parkes, Jay; Abercrombie, Sara; McCarty, Teresita

    2013-01-01

    The feedback sandwich technique-make positive comments; provide critique; end with positive comments-is commonly recommended to feedback givers despite scant evidence of its efficacy. These two studies (N = 20; N = 350) of written peer feedback with third-year medical students on clinical patient note-writing assignments indicate that students…

  2. X-joints in composite sandwich panels

    NARCIS (Netherlands)

    Vredeveldt, A.W.; Janssen, G.Th.M.

    1998-01-01

    The small structural weight of fast large ships such as fast mono hulls or catamaran type of ships is of extreme importance to their success. One possible light weight structural solution is the sandwich panel with fibre reinforced laminates and a balsa, honeycomb or foam core. A severe obstacle for

  3. Fuzzy logic membership implementation using optical hardware components

    Science.gov (United States)

    Moniem, T. A.; Saleh, M. H.

    2012-10-01

    Intelligent control techniques consist of knowledge-based expert or fuzzy logic control. One obvious drawback in many such applications is that fuzzy logic memberships are implemented at the lowest level. In high-bandwidth processes, this form of fuzzy logic membership implementation would require high speed and accuracy in the presence of strong nonlinearities and dynamic coupling. This paper presents a novel methodology called the Opto-fuzzy method to design a fuzzy logic membership using an optical hardware component. The proposed scheme is applied to triangular-shaped and half trapezoidal-shaped membership functions.

  4. 7 CFR 930.20 - Establishment and membership.

    Science.gov (United States)

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TART CHERRIES GROWN IN THE STATES... Cherry Industry Administrative Board, the membership of which shall be calculated in accordance...

  5. HYBRID-SANDWICHED REINFORCEMENT WITH GEOSYNTHETICS

    Science.gov (United States)

    Yasuhara, Kazuya; Yamazaki, Shinji; Sakakibara, Tsutomu

    Advantageous aspects of sandwich-type reinforced earth structures combined with geosynthetics and sand mat are highlighted in this paper. Those aspects were elucidated by two kinds of laboratory tests : (1) large consolidation tests for improvement of hydraulic conductivity and (2) model footing tests on improvement of bearing capacity and deformation characteristics for reinforced earth structures, including both vertical permeability and horizontal transmissibility characteristics of geosynthetics results from both laboratory tests indicated the following: i) Hydraulic conductivity of geosynthetics used for this type of earth reinforcement can be maintained for a long period. Such conductivity sometimes disappears, particularly because of clogging when geosynthetics are adopted in embankment construction using fine-grained soils. This fact indicates that the sand mats which are laid above and beneath geosynthetics play a salient role in preventing clogging of geosynthetics that occurs by intrusion of fines from cohesive soils. ii) Sandwich-type reinforcement combined with geosynthetics and sand mats increases stability and decreases deformation of earth structures. In particular, the sandwich structure is effective for providing toughness, which has remained an important issue for reducing infrastructural maintenance and costs. In the later part of the paper, conventionally available stability analysis was carried out to propose the design procedure for reinforced earth structures and at the same time numerical analysis was also conducted to ensure the applicability of the hybrid-sandwiched earth reinforcement newly proposed in the current paper. Finally, based on the horizontal placement by means of HBS described in the current paper, the vertical drain procedure using the sandwich structures for accelerating consolidation and increasing stability of soft soils is also suggested for the future research and investigation.

  6. Rough function model and rough membership function

    Institute of Scientific and Technical Information of China (English)

    Wang Yun; Guan Yanyong; Huang Zhiqin

    2008-01-01

    Two pairs of approximation operators, which are the scale lower and upper approximations as well as the real line lower and upper approximations, are defined. Their properties and antithesis characteristics are analyzed. The rough function model is generalized based on rough set theory, and the scheme of rough function theory is made more distinct and complete. Therefore, the transformation of the real function analysis from real line to scale is achieved. A series of basic concepts in rough function model including rough numbers, rough intervals, and rough membership functions are defined in the new scheme of the rough function model. Operating properties of rough intervals similar to rough sets are obtained. The relationship of rough inclusion and rough equality of rough intervals is defined by two kinds of tools, known as the lower (upper) approximation operator in real numbers domain and rough membership functions. Their relative properties are analyzed and proved strictly, which provides necessary theoretical foundation and technical support for the further discussion of properties and practical application of the rough function model.

  7. Impact Delamination and Fracture in Aluminum/Acrylic Sandwich Plates

    Science.gov (United States)

    Liaw, Benjamin; Zeichner, Glenn; Liu, Yanxiong; Bowles, Kenneth J. (Technical Monitor)

    2000-01-01

    Impact-induced delamination and fracture in 6061-T6 aluminum/cast acrylic sandwich plates adhered by epoxy were generated in an instrumented drop-weight impact machine. Although only a small dent was produced on the aluminum side when a hemispherical penetrator tup was dropped onto it from a couple of inches, a large ring of delamination at the interface was observed. The delamination damage was often accompanied by severe shattering in the acrylic substratum. Damage patterns in the acrylic layer include radial and ring cracks and, together with delamination at the interface, may cause peeling-off of acrylic material from the sandwich plate. Theory of stress-wave propagation can be used to explain these damage patterns. The impact tests were conducted at various temperatures. The results also show clearly that temperature effect is very important in impact damage. For pure cast acrylic nil-ductile transition (NDT) occurs between 185-195 F. Excessive impact energy was dissipated into fracture energy when tested at temperature below this range or through plastic deformation when tested at temperature above the NDT temperature. Results from this study will be used as baseline data for studying fiber-metal laminates, such as GLARE and ARALL for advanced aeronautical and astronautical applications.

  8. Proposal of SNS Membership Qualification System for Information Security

    OpenAIRE

    佐藤, 直; 岡田, 康義; Naoshi, SATO; Yasuyoshi, OKADA; 情報セキュリティ大学院大学 情報セキュリティ研究科; Institute of Information Security

    2013-01-01

    For assuring information security of SNS, the paper proposes introducing the SNS membership qualification system which uses 3 types of licenses and certifications; SNS membership license, security inspection certificate and access visa. It further describes related organization and operating image of the proposed system, and finally discusses effects and issues on the proposal from technical and sociological viewpoints.

  9. 12 CFR 725.6 - Termination of membership.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Termination of membership. 725.6 Section 725.6 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS NATIONAL CREDIT UNION ADMINISTRATION CENTRAL LIQUIDITY FACILITY § 725.6 Termination of membership. (a) A member...

  10. Three Steps to Engage Volunteers in Membership Marketing

    Science.gov (United States)

    Rossell, Tony

    2011-01-01

    There is a big world out there, and volunteers can make a significant impact in helping one reach out to others and grow his/her PTA membership. In fact, word-of-mouth marketing tied for the top spot as the most effective method of new member recruitment in Marketing General's 2010 Membership Marketing Benchmarking Report. So getting volunteers'…

  11. 44 CFR 19.215 - Membership practices of certain organizations.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Membership practices of certain organizations. 19.215 Section 19.215 Emergency Management and Assistance FEDERAL EMERGENCY... Title IX regulations do not apply to the membership practices of a voluntary youth service...

  12. 7 CFR 948.151 - Colorado Potato Committee membership.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Colorado Potato Committee membership. 948.151 Section... POTATOES GROWN IN COLORADO Rules and Regulations Modification of Inspection Requirements § 948.151 Colorado Potato Committee membership. The Colorado Potato Committee shall be comprised of six members...

  13. Membership, Belonging, and Identity in the Twenty-First Century

    Science.gov (United States)

    Motteram, Gary

    2016-01-01

    This article takes a case study approach to exploring membership, belonging, and identity amongst English language teachers in the twenty-first century. It explores findings from two membership surveys conducted for the International Association of Teachers of English as a Foreign Language (IATEFL), and considers the impact of recommendations…

  14. Membership, Belonging, and Identity in the Twenty-First Century

    Science.gov (United States)

    Motteram, Gary

    2016-01-01

    This article takes a case study approach to exploring membership, belonging, and identity amongst English language teachers in the twenty-first century. It explores findings from two membership surveys conducted for the International Association of Teachers of English as a Foreign Language (IATEFL), and considers the impact of recommendations…

  15. 75 FR 59704 - Office of Management; Performance Review Board Membership

    Science.gov (United States)

    2010-09-28

    ... Office of Management; Performance Review Board Membership AGENCY: Department of Education. ACTION: Notice of membership of the Performance Review Board. SUMMARY: The Secretary announces the members of the Performance Review Board (PRB) for the Department of Education for the Senior Executive Service...

  16. 10 CFR 5.215 - Membership practices of certain organizations.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Membership practices of certain organizations. 5.215 Section 5.215 Energy NUCLEAR REGULATORY COMMISSION NONDISCRIMINATION ON THE BASIS OF SEX IN EDUCATION PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Coverage § 5.215 Membership practices...

  17. 12 CFR 614.4267 - Professional association membership; competency.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Professional association membership; competency...; competency. (a) Membership in appraisal organizations. A State certified appraiser or a State licensed...) Competency. All staff and fee evaluators, including appraisers, performing evaluations in connection...

  18. 12 CFR 225.66 - Professional association membership; competency.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Professional association membership; competency...; competency. (a) Membership in appraisal organizations. A State certified appraiser or a State licensed...) Competency. All staff and fee appraisers performing appraisals in connection with federally...

  19. The Effect of Religious Membership on Teen Abortion Rates.

    Science.gov (United States)

    Tomal, Annette

    2001-01-01

    Studied abortion rates among teenagers in 1,024 counties in 18 states that report abortion numbers. Results show that counties with high levels of religious membership were more likely to be in a state with a parental involvement law for teenage abortions. Both religious membership level and a parental involvement law were negatively related to…

  20. Young Doctor Movements: motives for membership among aspiring and young family physicians.

    Science.gov (United States)

    Yakubu, Kenneth; Hoedebecke, Kyle; Nashat, Nagwa

    2015-01-01

    Over the past decade, young doctor movements (YDMs) have gained recognition for their efforts in promoting the discipline of family medicine. With growth and expansion comes the need for an inquiry into the membership motives of current/intending members. This study was aimed at determining the main reasons why young and aspiring family physicians (FPs) joined their regional YDM. It was also concerned with determining the main factors that will make non-members want to join a YDM as well as assessing for differences in the responses within YDM members on the one hand, and between YDM members and non-members on the other. This was a cross-sectional web-based study. Using a list of 11 items generated following a series of discussions and feedback among selected FPs and FP trainees, respondents annotated levels of agreement on reasons for current or desired YDM membership. The Mann-Whitney U test was used to determine the distribution and differences in the mean of rank scores of the responses from YDM and non-YDM members while the Kruskal-Wallis test was used to describe same for the various YDMs. The total number of respondents was 200, out of which 102 (51.0%) were current YDM members, 97 (48.5%) were non-members and 1 (0.5%) respondent did not state his/her membership status. Non-YDM members indicated a predominantly academic/professional motive for membership while YDM members indicated the opportunity to socialise with FPs abroad and in their country as their foremost reasons for membership. A mixture of academic, professional and social motives was observed for respondents from Vasco da Gama; predominantly academic and professional motives for respondents from Spice route. While gaining recognition and improving one's practice may be the ultimate goal of an aspiring FP, socialising within a network of like-minded professionals maybe the young FP's way of coping with demands of the discipline.

  1. Infinite multiple membership relational modeling for complex networks

    DEFF Research Database (Denmark)

    Mørup, Morten; Schmidt, Mikkel Nørgaard; Hansen, Lars Kai

    2011-01-01

    Learning latent structure in complex networks has become an important problem fueled by many types of networked data originating from practically all fields of science. In this paper, we propose a new non-parametric Bayesian multiple-membership latent feature model for networks. Contrary to exist......Learning latent structure in complex networks has become an important problem fueled by many types of networked data originating from practically all fields of science. In this paper, we propose a new non-parametric Bayesian multiple-membership latent feature model for networks. Contrary...... to existing multiplemembership models that scale quadratically in the number of vertices the proposed model scales linearly in the number of links admitting multiple-membership analysis in large scale networks. We demonstrate a connection between the single membership relational model and multiple membership...

  2. A novel classification method based on membership function

    Science.gov (United States)

    Peng, Yaxin; Shen, Chaomin; Wang, Lijia; Zhang, Guixu

    2011-03-01

    We propose a method for medical image classification using membership function. Our aim is to classify the image as several classes based on a prior knowledge. For every point, we calculate its membership function, i.e., the probability that the point belongs to each class. The point is finally labeled as the class with the highest value of membership function. The classification is reduced to a minimization problem of a functional with arguments of membership functions. Three novelties are in our paper. First, bias correction and Rudin-Osher-Fatemi (ROF) model are adopted to the input image to enhance the image quality. Second, unconstrained functional is used. We use variable substitution to avoid the constraints that membership functions should be positive and with sum one. Third, several techniques are used to fasten the computation. The experimental result of ventricle shows the validity of this approach.

  3. On the Milnor fibers of sandwiched singularities

    CERN Document Server

    Nemethi, Andras

    2009-01-01

    The sandwiched surface singularities are those rational surface singularities which dominate birationally smooth surface singularities. de Jong and van Straten showed that one can reduce the study of the deformations of a sandwiched surface singularity to the study of deformations of a 1-dimensional object, a so-called decorated plane curve singularity. In particular, the Milnor fibers corresponding to their various smoothing components may be reconstructed up to diffeomorphisms from those deformations of associated decorated curves which have only ordinary singularities. Part of the topology of such a deformation is encoded in the incidence matrix between the irreducible components of the deformed curve and the points which decorate it, well-defined up to permutations of columns. Extending a previous theorem ofours, which treated the case of cyclic quotient singularities, we show that the Milnor fibers which correspond to deformations whose incidence matrices are different up to permutations of columns are n...

  4. Utilization of Bamboo as Lightweight Sandwich Panels

    Directory of Open Access Journals (Sweden)

    Suthon SRIVARO

    2016-05-01

    Full Text Available Lightweight sandwich panels consisting of bamboo faces and oil palm trunk core were manufactured using melamine urea formaldehyde with the resin content of 250 g/m2 (solid basis. The parameters examined were node and density of bamboo faces. Physical (board density, thickness swelling and water absorption and mechanical (modulus of elasticity and modulus of rupture properties of the sandwich board obtained were investigated and compared with other bamboo products and commercial wood based products. Result showed that this panel had better dimensional stability than those of other bamboo products but lower bending strength. Node of bamboo had no significant effect on any board properties examined. Most of board properties were influenced by bamboo face density. Comparing the properties to commercial wood based products, this panel could be used as wall/floor applications.

  5. Buckling optimisation of sandwich cylindrical panels

    Science.gov (United States)

    Abouhamzeh, M.; Sadighi, M.

    2016-06-01

    In this paper, the buckling load optimisation is performed on sandwich cylindrical panels. A finite element program is developed in MATLAB to solve the governing differential equations of the global buckling of the structure. In order to find the optimal solution, the genetic algorithm Toolbox in MATLAB is implemented. Verifications are made for both the buckling finite element code and also the results from the genetic algorithm by comparisons to the results available in literature. Sandwich cylindrical panels are optimised for the buckling strength with isotropic or orthotropic cores with different boundary conditions. Results are presented in terms of stacking sequence of fibers in the face sheets and core to face sheet thickness ratio.

  6. Utilization of Bamboo as Lightweight Sandwich Panels

    Directory of Open Access Journals (Sweden)

    Suthon SRIVARO

    2016-05-01

    Full Text Available Lightweight sandwich panels consisting of bamboo faces and oil palm trunk core were manufactured using melamine urea formaldehyde with the resin content of 250 g/m2 (solid basis. The parameters examined were node and density of bamboo faces. Physical (board density, thickness swelling and water absorption and mechanical (modulus of elasticity and modulus of rupture properties of the sandwich board obtained were investigated and compared with other bamboo products and commercial wood based products. Result showed that this panel had better dimensional stability than those of other bamboo products but lower bending strength. Node of bamboo had no significant effect on any board properties examined. Most of board properties were influenced by bamboo face density. Comparing the properties to commercial wood based products, this panel could be used as wall/floor applications.

  7. Joint Membership between AAS, ASP, and IDA

    Science.gov (United States)

    Loth, A. L.; Upgren, A. R.

    2001-12-01

    Three societies of great importance to astronomers are the American Astronomical Society, the Astronomical Society of the Pacific, and the International DarkSky Association. As of spring 2001 their membership totals were reported as 5353, 4549, and 7362 members, respectively. It is of interest to determine the numbers of members these groups have in common. A comparison of the roles of each group has been made; the IDA list was examined twice due to its very rapid growth; in 2000 when the count was 4414, and 2001 when it was 7362. The results show that the more recent members of the IDA include higher percentages of members of the other two groups than those who joined the IDA before 2000. Some part of this percentage increase is probably due to a recent emphasis on the promotion of dark skies within the astronomical community, and the growing success of light-pollution control legislation.

  8. A spiral antenna sandwiched by dielectric layers

    OpenAIRE

    Nakano, Hisamatsu; Ikeda, Masakazu; Hitosugi, Kazuo; Yamauchi, Junji

    2004-01-01

    An infinitesimally thin spiral antenna, sandwiched by bottom and top dielectric layers having the same relative permittivity, is analyzed under the condition that the dielectric layers are of finite extent and the antenna is backed by an infinite conducting plane. As the thickness of the top dielectric layer increases, the input impedance and axial ratio (AR) vary in an oscillatory fashion, with a period slightly larger than one-half of the guided wavelength of a wave propagating in an unboun...

  9. Self-healing sandwich composite structures

    Science.gov (United States)

    Fugon, D.; Chen, C.; Peters, K.

    2012-04-01

    Previous research demonstrated that a thin self-healing layer is effective in recovering partial sandwich composite performance after an impact event. Many studies have been conducted that show the possibility of using Fiber Bragg Grating (FBG) sensors to monitor the cure of a resin through strain and temperature monitoring. For this experiment, FBG sensors were used to monitor the curing process of a self-healing layer within a twelve-layer fiberglass laminate after impact. First, five self-healing sandwich composite specimens were manufactured. FBG sensors were embedded between the fiberglass and foam core. Then the fiberglass laminate was impacted with the use of a drop tower and the curing process was monitored. The collected data was used to compare the cure of the resin and fiberglass alone to the cure of the resin from a self-healing specimen. For the low viscosity resin system tested, these changes were not sufficiently large to identify different polymerization states in the resin as it cured. These results indicate that applying different resin systems might increase the efficiency of the self-healing in the sandwich composites.

  10. Mixed auxeticity of auxetic sandwich structures

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Teik-Cheng [SIM University, Singapore (Singapore)

    2012-07-15

    Previously, a sandwich structure in which the Poisson ratios of the core and facesheets possess opposite signs has been shown to exhibit overall conventional and auxetic behavior depending on the loading mode - axial loading or bending - for an intermediate range of relative core thickness. In addition to these two loading modes, sandwich structures in aerospace applications encounter torsional loads. In this paper, the effective Poisson's ratio for torsional loading is proposed. Results show that, depending on the loading mode and the relative core thickness, there can be up to four levels of overall auxeticity, namely (i) full auxeticity (FA) if the structure behaves as an auxetic structure under all three modes of loading, (ii) high auxeticity (HA) if the structure behaves as an auxetic structure in two of the loading modes, (iii) low auxeticity (LA) if the structure behaves as an auxetic structure in only one of the loading modes, and (iv) no auxeticity (NA) if the structure behaves as a conventional structure under all of the three loading modes. These results indicate that by selecting the Poisson's ratios and the thickness of the cores and facesheets, the sandwich structure can be made to respond differently under different external loading conditions. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Analysis of propagation characteristics of flexural wave in honeycomb sandwich panel and design of loudspeaker for radiating inclined sound

    Science.gov (United States)

    Fujii, Ayaka; Wakatsuki, Naoto; Mizutani, Koichi

    2015-07-01

    A loudspeaker for an auditory guiding system is proposed. This loudspeaker utilizes inclined sound transformed from a flexural wave in a honeycomb sandwich panel. We focused on the fact that the inclined sound propagates extensively with uniform level and direction. Furthermore, sound can be generated without group delay dispersion because the phase velocity of the flexural wave in the sandwich panel becomes constant with increasing frequency. These characteristics can be useful for an auditory guiding system in public spaces since voice-guiding navigation indicates the right direction regardless of position on a pathway. To design the proposed loudspeaker, the behavior of the sandwich panel is predicted using a theoretical equation in which the honeycomb core is assumed as an orthotropic continuum. We calculated the phase velocity dispersion of the flexural wave in the sandwich panel and compared the results obtained using the equation with those of a simulation based on the finite element method and an experiment in order to confirm the applicability of the theoretical equation. It was confirmed that the phase velocities obtained using the theoretical equation and by the simulation were in good agreement with that obtained experimentally. The obtained results suggest that the behavior of the sandwich panel can be predicted using the parameters of the panel. In addition, we designed an optimized honeycomb sandwich panel for radiating inclined sound by calculating the phase velocity characteristics of various panels that have different parameters of core height and cell size using the theoretical equation. Sound radiation from the optimized panel was simulated and compared with that of a homogeneous plate. It was clear that the variance of the radiation angle with varying frequency of the optimized panel was smaller than that of the homogeneous plate. This characteristic of sound radiation with a uniform angle is useful for indicating the destination direction. On

  12. Design of an electro-Fenton system with a novel sandwich film cathode for wastewater treatment.

    Science.gov (United States)

    Fan, Yan; Ai, Zhihui; Zhang, Lizhi

    2010-04-15

    In this study, we demonstrate an electro-Fenton (E-Fenton) system constructed with a novel sandwich film cathode (SFC). For the fabrication of SFC, Fe(2+)-chitosan (Fe-CHI) was first deposited on foam nickel (Fe-CHI/Ni). Then two pieces of Fe-CHI/Ni was used to fasten one piece of activated carbon fiber (ACF) to obtain a Fe-CHI/Ni|ACF|Fe-CHI/Ni sandwich film cathode. We interestingly found that this SFC based E-Fenton system could effectively degrade rodamine B with in situ generating both hydrogen peroxide and iron ions. Its degradation efficiency was significantly higher than those of the E-Fenton systems constructed with composite cathodes of carbon nanotubes with Fe@Fe(2)O(3) core-shell nanowires or Cu(2)O nanocubes reported in our previous studies. Hydrogen peroxide electrogenerated through the reduction of O(2) adsorbed on the sandwich film cathode and the iron ions produced by the leakage from Fe(2+)-chitosan film during the E-Fenton reaction were, respectively, monitored, providing clues to understand the high efficiency of this novel SFC based E-Fenton system. More importantly, this low-cost sandwich film cathode was very stable and could be reused without catalytic activity decrease, suggesting its potential application in the wastewater treatment.

  13. Unique Sandwiched Carbon Sheets@Ni-Mn Nanoparticles for Enhanced Oxygen Evolution Reaction.

    Science.gov (United States)

    Zhang, Yan; Zhang, Huijuan; Yang, Jiao; Bai, Yuanjuan; Qiu, Huajun; Wang, Yu

    2016-05-11

    A unique sandwich-like architecture, where Ni-Mn nanoparticles are enveloped in coupled carbon sheets (CS@Ni-Mn), has been successfully fabricated. In the synthesis process, a great quantity of uniform NiMnO3 nanosheets generated by a universal hydrothermal method acts as precursors and templates and the cheap, environmentally friendly and recyclable glucose functions as a green carbon source. Via subsequent hydrothermal reaction and thermal annealing, sandwiched nanocomposites with Ni-Mn nanoparticles embedded inside and carbon sheets encapsulating outside can be massively prepared. The novel sandwich-like CS@Ni-Mn possesses numerous advantages, such as an intrinsic porous feature, large specific surface area, and enhanced electronic conductivity. Moreover, as a promising NiMn-based oxygen evolution reaction (OER) catalyst, the special sandwiched nanostructure demonstrates improved electrochemical properties in 1 M KOH, including a low overpotential of about 250 mV, a modest Tafel slope of 40 mV dec(-1), excellent stability over 2000 cycles, and durability for 40 h.

  14. Response of Composite Fuselage Sandwich Side Panels Subjected to Internal Pressure and Axial Tension

    Science.gov (United States)

    Rouse, Marshall; Ambur, Damodar R.; Dopker, Bernard; Shah, Bharat

    1998-01-01

    The results from an experimental and analytical study of two composite sandwich fuselage side panels for a transport aircraft are presented. Each panel has two window cutouts and three frames and utilizes a distinctly different structural concept. These panels have been evaluated with internal pressure loads that generate biaxial tension loading conditions. Design limit load and design ultimate load tests have been performed on both panels. One of the sandwich panels was tested with the middle frame removed to demonstrate the suitability of this two-frame design for supporting the prescribed biaxial loading conditions with twice the initial frame spacing of 20 inches. A damage tolerance study was conducted on the two-frame panel by cutting a notch in the panel that originates at the edge of a cutout and extends in the panel hoop direction through the window-belt area. This panel with a notch was tested in a combined-load condition to demonstrate the structural damage tolerance at the design limit load condition. Both the sandwich panel designs successfully satisfied all desired load requirements in the experimental part of the study, and experimental results from the two-frame panel with and without damage are fully explained by the analytical results. The results of this study suggest that there is potential for using sandwich structural concepts with greater than the usual 20-in. wide frame spacing to further reduce aircraft fuselage structural weight.

  15. Thermal conductivity of newspaper sandwiched aerated lightweight concrete panel

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Soon-Ching; Low, Kaw-Sai [Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Genting Kelang, Setapak, 53300 Kuala Lumpur, Wilayah Persekutuan (Malaysia)

    2010-12-15

    Investigation on the thermal conductivity of newspaper sandwiched aerated lightweight concrete (ALC) panels is the main purpose of this study. Various densities of ALC panels ranging from 1700, 1400 and 1100 kg/m{sup 3} with three different aerial intensities of newspaper sandwiched were produced. Investigation was limited to the effect of aerial intensity of newspaper sandwiched and the effect of density of ALC on thermal conductivity. It is found that the thermal conductivity of newspaper sandwiched ALC panels reduced remarkably compared to control ALC panels. The reduction was recorded at 18.0%, 21.8% and 20.7% correspond to densities of 1700, 1400 and 1100 kg/m{sup 3} with just a mere 0.05 g/cm{sup 2} aerial intensity of newspaper sandwiched. Newspaper sandwiched has a significant impact on the performance of thermal conductivity of ALC panels based on regression analysis. (author)

  16. Democracy predicts sport and recreation membership: Insights from 52 countries.

    Science.gov (United States)

    Balish, Shea M

    2017-03-01

    Although evidence suggests sport and recreation are powerful contributors to worldwide public health, sizable gender differences persist. It is unknown whether country characteristics moderate gender differences across countries. The primary purpose of this study was to examine if countries' levels of democracy and/or gender inequality moderate gender differences in sport and recreation membership across countries. The secondary purpose was to examine if democracy and/or gender inequality predicts overall rates of sport and recreation membership for both males and females. This study involved a nested cross-sectional design and employed the sixth wave (2013) of the world value survey (nSs=71,901, ncountries=52). Multiple hierarchal nonlinear Bernoulli models tested: (1) if countries' levels of democracy moderate gender differences in sport and recreation membership; and (2) if democracy is associated with increased sport and recreation membership for both males and females. Countries' level of democracy fully moderated gender differences in sport and recreation membership across countries. Moreover, democracy was positively associated with both male and female membership, even when controlling for individual and country-level covariates. Democratic political regimes may confer health benefits via increased levels of sport and recreation membership, especially for females. Future research should test mediating mechanisms.

  17. Design Analysis of the Mixed Mode Bending Sandwich Specimen

    DEFF Research Database (Denmark)

    Quispitupa, Amilcar; Berggreen, Christian; Carlsson, Leif A.

    2010-01-01

    A design analysis of the mixed mode bending (MMB) sandwich specimen for face–core interface fracture characterization is presented. An analysis of the competing failure modes in the foam cored sandwich specimens is performed in order to achieve face–core debond fracture prior to other failure modes....... The analysis facilitates selection of the appropriate geometry for the MMB sandwich specimen to promote debond failure. An experimental study is performed using MMB sandwich specimens with a H100 PVC foam core and E-glass–polyester faces. The results reveal that debond propagation is successfully achieved...... for the chosen geometries and mixed mode loading conditions....

  18. Influence of plywood grain direction on sandwich panel bending properties

    OpenAIRE

    Jaroslav Kljak; Mladen Brezović; Alan Antonović

    2009-01-01

    This paper investigates the influence of plywood grain direction on bending properties of a sandwich panel, as well as on stress distribution in each layer. Experimental sandwich panels (tnom= 29 mm) were made of two three-ply plywood panels and a rigid PVC core between them. Grain directions of plywood panels were between 0° and 90°, continuously raised by 15°. Seven models of sandwich panels were made. Bending properties of a sandwich panel was determined by three point bending method and s...

  19. Buckling Analysis of Debonded Sandwich Panel Under Compression

    Science.gov (United States)

    Sleight, David W.; Wang, John T.

    1995-01-01

    A sandwich panel with initial through-the-width debonds is analyzed to study the buckling of its faceskin when subject to an in-plane compressive load. The debonded faceskin is modeled as a beam on a Winkler elastic foundation in which the springs of the elastic foundation represent the sandwich foam. The Rayleigh-Ritz and finite-difference methods are used to predict the critical buckling load for various debond lengths and stiffnesses of the sandwich foam. The accuracy of the methods is assessed with a plane-strain finite-element analysis. Results indicate that the elastic foundation approach underpredicts buckling loads for sandwich panels with isotropic foam cores.

  20. Analytical determination of the ultimate strength of sandwich beams

    Science.gov (United States)

    Theotokoglou, Efstathios E.

    1996-09-01

    An analytical determination of the ultimate strength of a typical GRP/PVC sandwich beam has been performed. These beams represent common building practise in marine applications. Equations describing the behaviour of a sandwich panel under beam loading and various failure modes have been developed. The method has been applied to predict the ultimate load for a simple supported sandwich beam. The critical loads have been compared with those from the experimental investigation of a typical bulkhead-to-hull GRP/PVC sandwich T-joint under pull out forces.

  1. Elastic constants for superplastically formed/diffusion-bonded sandwich structures

    Science.gov (United States)

    Ko, W. L.

    1979-01-01

    Formulae and the associated graphs are presented for contrasting the effective elastic constants for a superplastically formed/diffusion-bonded (SPF/DB) corrugated sandwich core and a honeycomb sandwich core. The results used in the comparison of the structural properties of the two types of sandwich cores are under conditions of equal sandwich density. It was found that the stiffness in the thickness direction of the optimum SPF/DB corrugated core (i.e., triangular truss core) was lower than that of the honeycomb core, and that the former had higher transverse shear stiffness than the latter.

  2. Infinite Multiple Membership Relational Modeling for Complex Networks

    DEFF Research Database (Denmark)

    Mørup, Morten; Schmidt, Mikkel Nørgaard; Hansen, Lars Kai

    Learning latent structure in complex networks has become an important problem fueled by many types of networked data originating from practically all fields of science. In this paper, we propose a new non-parametric Bayesian multiplemembership latent feature model for networks. Contrary to existing...... multiplemembership models that scale quadratically in the number of vertices the proposedmodel scales linearly in the number of links admittingmultiple-membership analysis in large scale networks. We demonstrate a connection between the single membership relational model and multiple membership models and show...

  3. Professional organization membership: Advancing the nurse practitioner role.

    Science.gov (United States)

    Goolsby, Mary Jo; DuBois, Janet C

    2017-08-01

    With a paucity of literature on professional organization membership by nurse practitioners (NPs), the authors base the discussion of the personal benefits associated with membership on literature focusing on clinicians other than NPs and their personal experiences as members of multiple organizations. Membership is described as related to NP socialization, engagement, networking, mentorship, advocacy, policy, leadership development, research dissemination, professional development, and volunteerism. In addition to encouraging active participation in one or more professional organizations, the need for research into factors influencing the degree to which NPs participate in organizations and the associated benefits is identified. ©2017 American Association of Nurse Practitioners.

  4. Generations.

    Science.gov (United States)

    Chambers, David W

    2005-01-01

    Groups naturally promote their strengths and prefer values and rules that give them an identity and an advantage. This shows up as generational tensions across cohorts who share common experiences, including common elders. Dramatic cultural events in America since 1925 can help create an understanding of the differing value structures of the Silents, the Boomers, Gen Xers, and the Millennials. Differences in how these generations see motivation and values, fundamental reality, relations with others, and work are presented, as are some applications of these differences to the dental profession.

  5. A double-sandwich ELISA for identification of monoclonal antibodies suitable for sandwich immunoassays

    Science.gov (United States)

    The sandwich immunoassay (sIA) is an invaluable technique for concentrating, detecting, and quantifying target antigens. The two critical components required are a capture antibody and a detection antibody, each binding a different epitope on the target antigen. The specific antibodies incorporated...

  6. EMMP :a highly efficient membership management protocol

    Institute of Scientific and Technical Information of China (English)

    LI Renfa; XIE Yunlong; WEN Jigang; YUE Guangxue

    2007-01-01

    Gossip (or epidemic) algorithms have recently become popular solutions to multicast message dissemination in peer-to-peer systems.Nevertheless,it is not straightforward to apply gossip to on-demand streaming because it often fails to achieve a timely delivery.To solve this problem and taking into account the characteristic of peers randomly joining and leaving in peer-to-peer systems,an Efficient Membership Management Protocol (EMMP) has been presented.Every node only needs to keep contact with O (log(N)) nodes,and EMMP can support the reliable dissemination of messages.Considering the "distance" between peers,it causes the major data to be transmitted in a local area and reduces the backbone's traffic,and speeds up the dissemination of messages between peers.This paper has adopted the"goodfriend" mechanism to reduce the influence on the system when a peer fails or leaves.Simulation results show that EMMP is highly efficient,and both the redundancy and the delay of the system are well solved.

  7. On curves on sandwiched surface singularities

    OpenAIRE

    Fernandez-Sanchez, Jesus

    2007-01-01

    Fixed a point O on a non-singular surface S and a complete mO-primary ideal I in its local ring, the curves on the surface X obtained by blowing-up I are studied in terms of the base points of I. Criteria for the principality of these curves are obtained. New formulas for their multiplicity, intersection numbers and order of singularity at the singularities of X are given. The semigroup of branches going through a sandwiched singularity is effectively determined, too.

  8. Failure modes of composite sandwich beams

    Directory of Open Access Journals (Sweden)

    Gdoutos E.

    2008-01-01

    Full Text Available A thorough investigation of failure behavior of composite sandwich beams under three-and four-point bending was undertaken. The beams were made of unidirectional carbon/epoxy facings and a PVC closed-cell foam core. The constituent materials were fully characterized and in the case of the foam core, failure envelopes were developed for general two-dimensional states of stress. Various failure modes including facing wrinkling, indentation failure and core failure were observed and compared with analytical predictions. The initiation, propagation and interaction of failure modes depend on the type of loading, constituent material properties and geometrical dimensions.

  9. Recent trends in aluminum foam sandwich technology

    Energy Technology Data Exchange (ETDEWEB)

    Banhart, John [TU Berlin, Materials Science and Technology, Hardenbergstr. 36, 10623 Berlin (Germany); Helmholtz-Centre Berlin, Hahn-Meitner-Platz, 14109 Berlin (Germany); Seeliger, Hans-Wolfgang [Pohltec Metalfoam GmbH, Robert-Bosch-Str. 6D, 50769 Koeln (Germany)

    2012-12-15

    We review the status of aluminum foam sandwich (AFS) technology and discuss both recent improvements of foaming technology and current application strategies. It is concluded that the quality of foams has improved in the past years but the costs are still very much the same. This is why applications in which metal foams have more than one function are more likely to be economically viable. The examples presented include electromagnetic shielding, carrier plates for mirrors, cooking equipment, architectural panels, and blast protection. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. CCPIT has awarded an honorary membership to Yoshio Nakata

    Institute of Scientific and Technical Information of China (English)

    Li Yinghong; Liu Jinliang

    2006-01-01

    @@ The China Council for the Promotion of International Trade (CCPIT) has awarded an honorary membership to Yoshio Nakata, chairman of the Japan Association for the Promotion of International Trade (JAPIT).

  11. CCPIT has awarded an honorary membership to Yoshio Nakata

    Institute of Scientific and Technical Information of China (English)

    Li; Yinghong; Liu; Jinliang

    2006-01-01

      The China Council for the Promotion of International Trade (CCPIT) has awarded an honorary membership to Yoshio Nakata, chairman of the Japan Association for the Promotion of International Trade (JAPIT).……

  12. 78 FR 76598 - Membership of the Performance Review Board

    Science.gov (United States)

    2013-12-18

    ... Review Board that oversees the evaluation of performance appraisals of Senior Executive Service members... FURTHER INFORMATION CONTACT: Andrea Burckman, Director, Executive Resources Division, Human Capital and... Membership of the Performance Review Board AGENCY: Office of Management, Department of Education....

  13. 76 FR 81998 - Senior Executive Service Performance Review Board Membership

    Science.gov (United States)

    2011-12-29

    ... Service PRB. The PRB reviews and evaluates the initial appraisal of a senior executive's performance by... Risinger, Human Resources Director, Federal Housing Finance Agency; and Joel R. Schapira, Deputy General... HEALTH REVIEW COMMISSION Senior Executive Service Performance Review Board Membership...

  14. Membership in social networks and the application in information filtering

    CERN Document Server

    Zeng, Wei; Shang, Ming-Sheng; Zhang, Yi-Cheng

    2013-01-01

    During the past a few years, users' membership in the online system (i.e. the social groups that online users joined) are wildly investigated. Most of these works focus on the detection, formulation and growth of online communities. In this paper, we study users' membership in a coupled system which contains user-group and user-object bipartite networks. By linking users' membership information and their object selection, we find that the users who have collected only a few objects are more likely to be "influenced" by the membership when choosing objects. Moreover, we observe that some users may join many online communities though they collected few objects. Based on these findings, we design a social diffusion recommendation algorithm which can effectively solve the user cold-start problem. Finally, we propose a personalized combination of our method and the hybrid method in [PNAS 107, 4511 (2010)], which leads to a further improvement in the overall recommendation performance.

  15. Barras bravas membership and its influence on drug use

    OpenAIRE

    López-Quintero, Catalina; Braun School of Public Health & Community Medicine, Hebrew University-Hadassah. Jerusalen, Israel. Médico, doctora en Salud Pública.; Neumark, Yehuda; Braun School of Public Health & Community Medicine, Hebrew University-Hadassah. Jerusalen, Israel. Médico, doctora en Salud Pública y Epidemiología.

    2014-01-01

    Objectives. To identify the factors associated with barras bravas (soccer fans clubs) membership, the incidence in drug use and the association between membership and drug use. Materials and methods. This report analyzed data from 1303 adolescent scholars who participated in two stages (T1 and T2) of a longitudinal study done in 23 schools of Bogota during 2006- 2007, selected through a probabilistic sampling stratified by clusters. Logistic regression models were implemented in order to eval...

  16. UPMASK: Unsupervised Photometric Membership Assignment in Stellar Clusters

    Science.gov (United States)

    Krone-Martins, Alberto; Moitinho, Andre

    2015-04-01

    UPMASK, written in R, performs membership assignment in stellar clusters. It uses photometry and spatial positions, but can take into account other types of data. UPMASK takes into account arbitrary error models; the code is unsupervised, data-driven, physical-model-free and relies on as few assumptions as possible. The approach followed for membership assessment is based on an iterative process, principal component analysis, a clustering algorithm and a kernel density estimation.

  17. Dynamic Failure of Composite and Sandwich Structures

    CERN Document Server

    Abrate, Serge; Rajapakse, Yapa D S

    2013-01-01

    This book presents a broad view of the current state of the art regarding the dynamic response of composite and sandwich structures subjected to impacts and explosions. Each chapter combines a thorough assessment of the literature with original contributions made by the authors.  The first section deals with fluid-structure interactions in marine structures.  The first chapter focuses on hull slamming and particularly cases in which the deformation of the structure affects the motion of the fluid during the water entry of flexible hulls. Chapter 2 presents an extensive series of tests underwater and in the air to determine the effects of explosions on composite and sandwich structures.  Full-scale structures were subjected to significant explosive charges, and such results are extremely rare in the open literature.  Chapter 3 describes a simple geometrical theory of diffraction for describing the interaction of an underwater blast wave with submerged structures. The second section addresses the problem of...

  18. Sandwich materials for wind turbine blades

    Energy Technology Data Exchange (ETDEWEB)

    Thybo Thomsen, O. [Aalborg Univ., Dept. of Mechanical Engineering, Aalborg (Denmark)

    2006-07-01

    Wind turbine blades are being manufactured using polymer matrix composite materials (PMC), in a combination of monolithic (single skin) and sandwich composites. Present day designs are mainly based on glass fibre reinforced composites (GFRP), but for very large blades carbon fibre reinforced composites (CFRP) are being used increasingly, in addition to GFRP by several manufacturers to reduce the weight. The size of wind turbines have increased significantly over the last 25 years, and this trend is expected to continue in the future. Thus, it is anticipated that wind turbines with a rated power output in the range of 8-10 MW and a rotor diameter about 170-180 m will be developed and installed within the next 10-15 years. The paper presents an overview of current day design principles and materials technology applied for wind turbine blades, and it highlights the limitations and important design issues to be addressed for up-scaling of wind turbine blades from the current maximum length in excess of 61 m to blade lengths in the vicinity of 90 m as envisaged for future very large wind turbines. In particular, the paper discusses the potential advantages and challenges of applying sandwich type construction to a larger extent than is currently being practiced for the load carrying parts of wind turbine blades. (au)

  19. Quantum radiation from a sandwich black hole

    Science.gov (United States)

    Frolov, Valeri P.; Zelnikov, Andrei

    2017-02-01

    We discuss quantum radiation of a massless scalar field from a spherically symmetric nonsingular black hole with a finite lifetime. Namely, we discuss a sandwich black-hole model, where a black hole is originally created by a collapse of a null shell of mass M , and later, after some time Δ V , it is disrupted by the collapse of the other shell with negative mass -M . We assume that between the shells the metric is static and either coincides with the Hayward metric or with a special generalization of it. We show that in both cases for a sufficiently large parameter Δ V the radiation after the formation of the black hole practically coincides with the Hawking result. We also calculate the radiation, emitted from the black hole interior. This radiation contains a peak at the moment when the second shell intersects the inner horizon. In the standard sandwich metric (with the Hayward interior) this outburst of energy is exponentially large. In the modified metric, which includes an additional nontrivial redshift parameter, this exponent is suppressed. This is a result of a significant decrease of the surface gravity of the inner horizon in the latter case. We discuss possible consequences of this result in the context of the self-consistency requirement for nonsingular models with quantum radiation.

  20. Fracture Analysis of Debonded Sandwich Columns Under Axial Compression

    DEFF Research Database (Denmark)

    May, A.; Avilés, F.; Berggreen, Christian

    A sandwich structure consists of two strong and stiff face sheets bonded to a weak low density core. The large separation between the face sheets provides increased bending rigidity and strength at low weight cost. Thus, sandwich structures frequently present better mechanical properties than mon...

  1. Practical Instruction in Tissue Culture and Cytogenetics for Sandwich Students.

    Science.gov (United States)

    Williams, D. C.; Bishun, N. P.

    1973-01-01

    Describes the training and practical techniques taught to students involved in a sandwich course at the Tissue Culture and Cytogenetics Unit of the Marie Curie Memorial Foundation, Surrey, England. Students spend a minimum of six months involved in the sandwich course before returning to university for a final academic year. (JR)

  2. Query processing of pre-partitioned data using Sandwich Operators

    NARCIS (Netherlands)

    Baumann, S.; Boncz, P.A.; Sattler, K.-U.

    2012-01-01

    In this paper we present the Sandwich Operators, an elegant approach to exploit pre-sorting or pre-grouping from clustered storage schemes in operators such as Aggregation/Grouping, HashJoin, and Sort of a database management system. Thereby, each of these operator types is "sandwiched" by two new o

  3. Tailoring Sandwich Face/Core Interfaces for Improved Damage Tolerance

    DEFF Research Database (Denmark)

    Lundsgaard-Larsen, Christian; Berggreen, Christian; Carlsson, Leif A.

    2010-01-01

    Various modifications of the face/core interface in foam core sandwich specimens are examined in a series of two papers. This paper constitutes part I and describes the finite element analysis of a sandwich test specimen, i.e. a DCB specimen loaded by uneven bending moments (DCB-UBM). Using...

  4. Tailoring Sandwich Face/Core Interfaces for Improved Damage Tolerance

    DEFF Research Database (Denmark)

    Lundsgaard-Larsen, Christian; Berggreen, Christian; Carlsson, Leif A.

    2010-01-01

    A face/core debond in a sandwich structure may propagate in the interface or kink into either the face or core. It is found that certain modifications of the face/core interface region influence the kinking behavior, which is studied experimentally in the present paper. A sandwich double cantilever...

  5. Fracture Analysis of Debonded Sandwich Columns Under Axial Compression

    DEFF Research Database (Denmark)

    May, A.; Avilés, F.; Berggreen, Christian

    A sandwich structure consists of two strong and stiff face sheets bonded to a weak low density core. The large separation between the face sheets provides increased bending rigidity and strength at low weight cost. Thus, sandwich structures frequently present better mechanical properties than mon...

  6. Thick Plate Homogenization of Sandwich Panels Including Folded Cellular Cores

    OpenAIRE

    LEBEE, Arthur; Sab, Karam

    2011-01-01

    In the present work, we provide the Bending-Gradient homogenization scheme and apply it to a sandwich panel including the chevron pattern. It turns out that the shear forces stiffness of the sandwich panel is strongly influenced by a skin distortion phenomenon which cannot be neglected in conventional design.

  7. Finite Element Modeling of the Buckling Response of Sandwich Panels

    Science.gov (United States)

    Rose, Cheryl A.; Moore, David F.; Knight, Norman F., Jr.; Rankin, Charles C.

    2002-01-01

    A comparative study of different modeling approaches for predicting sandwich panel buckling response is described. The study considers sandwich panels with anisotropic face sheets and a very thick core. Results from conventional analytical solutions for sandwich panel overall buckling and face-sheet-wrinkling type modes are compared with solutions obtained using different finite element modeling approaches. Finite element solutions are obtained using layered shell element models, with and without transverse shear flexibility, layered shell/solid element models, with shell elements for the face sheets and solid elements for the core, and sandwich models using a recently developed specialty sandwich element. Convergence characteristics of the shell/solid and sandwich element modeling approaches with respect to in-plane and through-the-thickness discretization, are demonstrated. Results of the study indicate that the specialty sandwich element provides an accurate and effective modeling approach for predicting both overall and localized sandwich panel buckling response. Furthermore, results indicate that anisotropy of the face sheets, along with the ratio of principle elastic moduli, affect the buckling response and these effects may not be represented accurately by analytical solutions. Modeling recommendations are also provided.

  8. Optimization of sandwich composites fuselages under flight loads

    NARCIS (Netherlands)

    Yan, C.; Bergsma, O.; Koussios, S.; Zu, L.; Beukers, A.

    2010-01-01

    The sandwich composites fuselages appear to be a promising choice for the future aircrafts because of their structural efficiency and functional integration advantages. However, the design of sandwich composites is more complex than other structures because of many involved variables. In this paper,

  9. Design and manufacturing of bio-based sandwich structures

    CSIR Research Space (South Africa)

    John, Maya J

    2017-03-01

    Full Text Available The aim of this chapter is to discuss the design and manufacturing of bio-based sandwich structures. As the economic advantages of weight reduction have become mandatory for many advanced industries, bio-based sandwich panels have emerged...

  10. Development, testing, and numerical modeling of a foam sandwich biocomposite

    Science.gov (United States)

    Chachra, Ricky

    This study develops a novel sandwich composite material using plant based materials for potential use in nonstructural building applications. The face sheets comprise woven hemp fabric and a sap based epoxy, while the core comprises castor oil based foam with waste rice hulls as reinforcement. Mechanical properties of the individual materials are tested in uniaxial compression and tension for the foam and hemp, respectively. The sandwich composite is tested in 3 point bending. Flexural results are compared to a finite element model developed in the commercial software Abaqus, and the validated model is then used to investigate alternate sandwich geometries. Sandwich model responses are compared to existing standards for nonstructural building panels, showing that the novel material is roughly half the strength of equally thick drywall. When space limitations are not an issue, a double thickness sandwich biocomposite is found to be a structurally acceptable replacement for standard gypsum drywall.

  11. Uncertainty in Fuzzy Membership Functions for a River Water Quality Management Problem

    OpenAIRE

    Karmakar, Subhankar; Mujumdar, PP

    2004-01-01

    Uncertainty associated with fuzzy membership functions for a water quality management problem is addressed through interval grey numbers. The lower and upper bounds of the membership functions are expressed as interval grey numbers, and the membership functions are modeled as imprecise membership functions. A grey fuzzy optimization model for water quality management of a river system is developed. Application of the optimization model with imprecise membership functions is illustrated with a...

  12. Multilayered sandwich-like architecture containing large-scale faceted Al–Cu–Fe quasicrystal grains

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Dongxia; He, Zhanbing, E-mail: hezhanbing@ustb.edu.cn

    2016-01-15

    Faceted quasicrystals are structurally special compared with traditional crystals. Although the application of faceted quasicrystals has been expected, wide-scale application has not occurred owing to the limited exposure of the facets. Using a facile method of heat treatment, we synthesize a multilayered sandwich-like structure with each layer composed of large-scale pentagonal-dodecahedra of Al–Cu–Fe quasicrystals. Moreover, there are channels between the adjacent Al–Cu–Fe layers that serve to increase the exposure of the facets of quasicrystals. Scanning electron microscopy, transmission electron microscopy, and X-ray diffraction are used to characterize the multilayered architecture, and the generation mechanisms of this special structure are also discussed. - Highlights: • A multilayered sandwich-like structure is produced by a facile method. • Each layer is covered by large-scale faceted Al–Cu–Fe quasicrystals. • There are channels between the adjacent Al–Cu–Fe layers.

  13. Standard Test Method for Sandwich Corrosion Test

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This test method defines the procedure for evaluating the corrosivity of aircraft maintenance chemicals, when present between faying surfaces (sandwich) of aluminum alloys commonly used for aircraft structures. This test method is intended to be used in the qualification and approval of compounds employed in aircraft maintenance operations. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information. 1.3 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements appear in Section 9.

  14. Nanoparticle organization in sandwiched polymer brushes.

    Science.gov (United States)

    Curk, Tine; Martinez-Veracoechea, Francisco J; Frenkel, Daan; Dobnikar, Jure

    2014-05-14

    The organization of nanoparticles inside grafted polymer layers is governed by the interplay of polymer-induced entropic interactions and the action of externally applied fields. Earlier work had shown that strong external forces can drive the formation of colloidal structures in polymer brushes. Here we show that external fields are not essential to obtain such colloidal patterns: we report Monte Carlo and molecular dynamics simulations that demonstrate that ordered structures can be achieved by compressing a "sandwich" of two grafted polymer layers, or by squeezing a coated nanotube, with nanoparticles in between. We show that the pattern formation can be efficiently controlled by the applied pressure, while the characteristic length-scale, that is, the typical width of the patterns, is sensitive to the length of the polymers. Based on the results of the simulations, we derive an approximate equation of state for nanosandwiches.

  15. Development and Mechanical Behavior of FML/Aluminium Foam Sandwiches

    Science.gov (United States)

    Baştürk, S. B.; Tanoğlu, M.

    2013-10-01

    In this study, the Fiber-Metal Laminates (FMLs) containing glass fiber reinforced polypropylene (GFPP) and aluminum (Al) sheet were consolidated with Al foam cores for preparing the sandwich panels. The aim of this article is the comparison of the flexural properties of FML/Al foam sandwich panels bonded with various surface modification approaches (silane treatment and combination of silane treatment with polypropylene (PP) based film addition). The FML/foam sandwich systems were fabricated by laminating the components in a mould at 200 °C under 1.5 MPa pressure. The energy absorbtion capacities and flexural mechanical properties of the prepared sandwich systems were evaluated by mechanical tests. Experiments were performed on samples of varying foam thicknesses (8, 20 and 30 mm). The bonding among the sandwich components were achieved by various surface modification techniques. The Al sheet/Al foam sandwiches were also consolidated by bonding the components with an epoxy adhesive to reveal the effect of GFPP on the flexural performance of the sandwich structures.

  16. Wave propagation in sandwich panels with a poroelastic core.

    Science.gov (United States)

    Liu, Hao; Finnveden, Svante; Barbagallo, Mathias; Arteaga, Ines Lopez

    2014-05-01

    Wave propagation in sandwich panels with a poroelastic core, which is modeled by Biot's theory, is investigated using the waveguide finite element method. A waveguide poroelastic element is developed based on a displacement-pressure weak form. The dispersion curves of the sandwich panel are first identified as propagating or evanescent waves by varying the damping in the panel, and wave characteristics are analyzed by examining their motions. The energy distributions are calculated to identify the dominant motions. Simplified analytical models are also devised to show the main physics of the corresponding waves. This wave propagation analysis provides insight into the vibro-acoustic behavior of sandwich panels lined with elastic porous materials.

  17. A Debonded Sandwich Specimen Under Mixed Mode Bending (MMB)

    DEFF Research Database (Denmark)

    Quispitupa, Amilcar; Berggreen, Christian; Carlsson, Leif A.

    2008-01-01

    Face/core interface crack propagation in sandwich specimens is analyzed. A thorough analysis of the typical failure modes in sandwich composites was performed in order to design the MMB specimen to promote face/core debond fracture. Displacement, compliance and energy release rate expressions...... for the MMB specimen were derived from a superposition analysis. An experimental verification of the methodology proposed was performed using MMB sandwich specimens with H100 PVC foam core and E-glass/polyester non-crimp quadro-axial [0/45/90/-45]s DBLT-850 faces. Different mixed mode loadings were applied...

  18. Measuring Cohesive Laws for Interfaces in Sandwich Structures

    DEFF Research Database (Denmark)

    Lundsgaard-Larsen, Christian; Sørensen, Bent F.; Berggreen, Carl Christian

    2006-01-01

    Extraction of cohesive laws are conducted for interfaces in sandwich structures. Separation between face and core are driven by pure bending moments applied to double cantilever beam (DCB) specimens. By varying the ratio between moments applied to the beams the test is conducted for different mode...... mixities. The sandwich specimens consists of glass fiber faces and Divinycell H200 foam core with a pre-crack between face and core made with teflon film. Arbitrary stiffening of the sandwich faces with steel bars adhered to the faces reduces rotations and ensures that the method is useable for a wide...

  19. A Debonded Sandwich Specimen Under Mixed Mode Bending (MMB)

    DEFF Research Database (Denmark)

    Quispitupa, Amilcar; Berggreen, Christian; Carlsson, Leif A.

    2008-01-01

    Face/core interface crack propagation in sandwich specimens is analyzed. A thorough analysis of the typical failure modes in sandwich composites was performed in order to design the MMB specimen to promote face/core debond fracture. Displacement, compliance and energy release rate expressions...... for the MMB specimen were derived from a superposition analysis. An experimental verification of the methodology proposed was performed using MMB sandwich specimens with H100 PVC foam core and E-glass/polyester non-crimp quadro-axial [0/45/90/-45]s DBLT-850 faces. Different mixed mode loadings were applied...

  20. Measuring Cohesive Laws for Interfaces in Sandwich Structures

    DEFF Research Database (Denmark)

    Lundsgaard-Larsen, Christian; Sørensen, Bent F.; Berggreen, Carl Christian

    2006-01-01

    Extraction of cohesive laws are conducted for interfaces in sandwich structures. Separation between face and core are driven by pure bending moments applied to double cantilever beam (DCB) specimens. By varying the ratio between moments applied to the beams the test is conducted for different mode...... mixities. The sandwich specimens consists of glass fiber faces and Divinycell H200 foam core with a pre-crack between face and core made with teflon film. Arbitrary stiffening of the sandwich faces with steel bars adhered to the faces reduces rotations and ensures that the method is useable for a wide...

  1. Thermal behavior of a titanium honeycomb-core sandwich panel

    Science.gov (United States)

    Ko, William L.; Jackson, Raymond H.

    1991-01-01

    Finite element thermal stress analysis was performed on a rectangular titanium honecomb-core sandwich panel which is subjected to thermal load with a temperature gradient across its depth. The distributions of normal stresses in the face sheets and the face-sheet/sandwich-core interfacial shear stresses are presented. The thermal buckling of the heated face sheet was analyzed by assuming the face sheet to be resting on an elastic foundation representing the sandwich core. Thermal buckling curves and thermal buckling load surface are presented for setting the limit for temperature gradient across the panel depth.

  2. Sandwich Panel as a Structural Element of Overlap

    Directory of Open Access Journals (Sweden)

    Novikov Maxim

    2016-01-01

    Full Text Available This paper considers the issue of sandwich panels using as load-bearing structural elements. The comparison of deflections and critical failure loads were obtained by the results of the full-scale roof sandwich panels tests conducted by the company “Joris Ide” and the theoretical design, according to the calculation method described in Euronorms. Based on these results it was concluded that sandwich panels can be treated as a load-bearing structure only with more taught manufacturing requirements. Thus, the reduced spread of critical loads can be achieved.

  3. A Fuzzy Description Logic with Automatic Object Membership Measurement

    Science.gov (United States)

    Cai, Yi; Leung, Ho-Fung

    In this paper, we propose a fuzzy description logic named f om -DL by combining the classical view in cognitive psychology and fuzzy set theory. A formal mechanism used to determine object memberships automatically in concepts is also proposed, which is lacked in previous work fuzzy description logics. In this mechanism, object membership is based on the defining properties of concept definition and properties in object description. Moreover, while previous works cannot express the qualitative measurements of an object possessing a property, we introduce two kinds of properties named N-property and L-property, which are quantitative measurements and qualitative measurements of an object possessing a property respectively. The subsumption and implication of concepts and properties are also explored in our work. We believe that it is useful to the Semantic Web community for reasoning the fuzzy membership of objects for concepts in fuzzy ontologies.

  4. The impact of group membership on collaborative learning with wikis.

    Science.gov (United States)

    Matschke, Christina; Moskaliuk, Johannes; Kimmerle, Joachim

    2013-02-01

    The social web stimulates learning through collaboration. However, information in the social web is often associated with information about its author. Based on previous evidence that ingroup information is preferred to outgroup information, the current research investigates whether group memberships of wiki authors affect learning. In an experimental study, we manipulated the group memberships (ingroup vs. outgroup) of wiki authors by using nicknames. The designated group memberships (being fans of a soccer team or not) were completely irrelevant for the domain of the wiki (the medical disorder fibromyalgia). Nevertheless, wiki information from the ingroup led to more integration of information into prior knowledge as well as more increase of factual knowledge than information from the outgroup. The results demonstrate that individuals apply social selection strategies when considering information from wikis, which may foster, but also hinder, learning and collaboration. Practical implications for collaborative learning in the social web are discussed.

  5. The Effect of Membership Rules and Voting Schemes on the Success of International Climate Agreements

    Energy Technology Data Exchange (ETDEWEB)

    Finus, M. [Department of Economics Institute of Economic Theory, Hagen University, Hagen (Germany); Altamirano-Cabrera, Juan-Carlos; Van Ierland, E. [Department of Social Sciences Environmental Economics and Natural Resources Group, Wageningen University, Wageningen (Netherlands)

    2003-11-01

    We empirically test the role of membership rules and voting schemes for climate change coalitions with the STAbility of COalitions model (STACO). The model comprises twelve world regions and captures long-run effects of greenhouse gas accumulation. We apply three stability concepts that capture the notion of open membership and exclusive membership with majority and unanimity voting. We show that exclusive membership leads to superior outcomes than open membership and that unanimity voting is preferable to majority voting in welfare and environmental terms. Our results suggest restricting membership in future international environmental agreements and they provide a rationale for unanimity voting as applied in many international organizations.

  6. Trends in organised sport membership: impact on sustainability.

    Science.gov (United States)

    Eime, Rochelle; Payne, Warren; Harvey, Jack

    2009-01-01

    Sporting clubs play a key role in community-level physical activity. This study investigated participation trends in sport club membership. A survey of 50 State sports governing bodies in Victoria, Australia collected information on factors affecting membership trends. The records for four of these sports were analysed for the 6 years, 1998-2003. Three sports reported increases in total membership (average annual rates (AARs): 0.3, 1.9 and 12.4%), and one reported a decrease (AAR: -1.0%). There was a decrease in both the absolute number (AARs: -1.1%, -2.3%, and -3.5%) and the proportion (AARs: -0.5%, -0.7%, -1.7% and -2.3%) of adult members. The number of junior club members increased slightly over the 6-year period in two sports (AARs: 0.5% and 0.7%), increased substantially in one (AAR: 12.2%) and decreased in one (AAR: -6.7%). The number of members playing modified sports increased in two sports (AARs: 2.8% and 3.3%), increased substantially in one (AARs: 53.1%) and decreased in one (AAR: -16.3%). The introduction of modified sport for younger participants is relatively new, resulting in sports accessing a new market to maintain or increase their total membership. However, the influx of younger members was not matched by associated increases in adult members. This places increased pressure upon adult members to maintain the infrastructure to support younger members. The issues of decreased adult membership and increased junior membership need to be addressed in order to ensure that community sporting clubs can be sustained and fulfil their potential to act as a vehicle for public health initiatives.

  7. Development of monoclonal antibody-based sandwich ELISA for detection of dextran.

    Science.gov (United States)

    Wang, Sheng-Yu; Li, Zhe; Wang, Xian-Jiang; Lv, Sha; Yang, Yun; Zeng, Lian-Qiang; Luo, Fang-Hong; Yan, Jiang-Hua; Liang, Da-Feng

    2014-10-01

    Dextran as anti-nutritional factor is usually a result of bacteria activity and has associated serial problems during the process stream in the sugar industry and in medical therapy. A sensitive method is expected to detect dextran quantitatively. Here we generated four monoclonal antibodies (MAbs) against dextran using dextran T40 conjugated with bovine serum albumin (BSA) as immunogen in our lab following hybridoma protocol. Through pairwise, an MAb named D24 was determined to be conjugated with horseradish peroxidase (HRP) and was used in the establishment of a sensitive sandwich enzyme-linked immunosorbent assay (ELISA) method for determination of dextran, in which MAb D9 was chosen as a capture antibody. The detection limit and working scope of the developed sandwich ELISA method were 3.9 ng/mL and 7.8-500 ng/mL with a correlation coefficient of 0.9909. In addition, the cross-reaction assay demonstrated that the method possessed high specificity with no significant cross-reaction with dextran-related substances, and the recovery rate ranged from 96.35 to 102.00%, with coefficient of variation ranging from 1.58 to 6.94%. These results indicated that we developed a detection system of MAb-based sandwich ELISA to measure dextran and this system should be a potential tool to determine dextran levels.

  8. Numerical comparison of patch and sandwich piezoelectric transducers for transmitting ultrasonic waves

    Science.gov (United States)

    Loveday, Philip W.

    2006-03-01

    Guided wave ultrasonic inspection is becoming an important method of non-destructive testing for long, slender structures such as pipes and rails. Often it is desirable to use transducers that can strongly excite a specific mode of wave propagation in the waveguide. Piezoelectric patch transducers are frequently employed, by researchers, for exciting waves in beam like structures. Sonar systems frequently make use of resonant transducers, such as sandwich transducers, for acoustic wave generation and this principle has been used to excite waves in a rail. This paper compares the two transduction approaches, for launching bending waves in rectangular waveguides, with numerical modeling. The numerical modeling combined a waveguide finite element model, of the waveguide, with conventional three-dimensional piezoelectric finite element models of the transducers. The waveguide finite elements were formulated using a complex exponential to describe the wave propagation along the structure and conventional finite element interpolation over the area of the element. Consequently, only a two-dimensional finite element mesh covering the cross-section of the waveguide is required. The harmonic forced response of the waveguide was used to compute a complex dynamic stiffness matrix which represented the waveguide in the transducer model. The effects of geometrical parameters of patch and sandwich transducers were considered before the comparison was made. It appears that piezoelectric patch transducers offer advantages at low frequencies while sandwich transducers are superior at high frequencies, where resonance can be exploited, at the cost of more complex design.

  9. Evaluation of a Composite Sandwich Fuselage Side Panel with Damage and Subjected to Internal Pressure

    Science.gov (United States)

    Rouse, Marshall; Ambur, Damodar R.; Bodine, Jerry; Dopker, Bernhard

    1997-01-01

    The results from an experimental and analytical study of a composite sandwich fuselage side panel for a transport aircraft are presented. The panel has two window cutouts and three frames, and has been evaluated with internal pressure loads that generate biaxial tension loading conditions. Design limit load and design ultimate load tests have been performed on the graphite-epoxy sandwich panel with the middle frame removed to demonstrate the suitability of this two-frame design for supporting the prescribed biaxial loading conditions with twice the initial frame spacing of 20 inches. The two-frame panel was damaged by cutting a notch that originates at the edge of a cutout and extends in the panel hoop direction through the window-belt area. This panel with a notch was tested in a combined-load condition to demonstrate the structural damage tolerance at the design limit load condition. The two panel configurations successfully satisfied all design load requirements in the experimental part of the study, and the three-frame and two-frame panel responses are fully explained by the analysis results. The results of this study suggest that there is potential for using sandwich structural concepts with greater than the usual 20-in.-wide frame spacing to further reduce aircraft fuselage structural weight.

  10. Image segmentation based on scaled fuzzy membership functions

    DEFF Research Database (Denmark)

    Jantzen, Jan; Ring,, P.; Christiansen, Pernille

    1993-01-01

    As a basis for an automated interpretation of magnetic resonance images, the authors propose a fuzzy segmentation method. The method uses five standard fuzzy membership functions: small, small medium, medium, large medium, and large. The method fits these membership functions to the modes...... of interest in the image histogram by means of a piecewise-linear transformation. A test example is given concerning a human head image, including a sensitivity analysis based on the fuzzy area measure. The method provides a rule-based interface to the physician...

  11. Open star cluster: formation, parameters, membership and importance

    CERN Document Server

    Joshi, Gireesh C

    2016-01-01

    We have been represented the collective information of estimation procedures of parameters of the open clusters and put them together for showing the importance of clusters to understand their role in stellar evolution phenomenon. Moreover, we have been discussed about analytic techniques to determine the structural and dynamical properties of galactic clusters. The members of clusters provide unique opportunity to determine their basic parameters such as: age, metallicity, distance, reddening etc. The membership probabilities of stars of clusters is assigned through the various approaches and each approach provides different number of probable members of the cluster. Here, we have been briefly discussed about various approaches to determine the stellar membership within clusters.

  12. Successful mouse hepatocyte culture with sandwich collagen gel formation

    National Research Council Canada - National Science Library

    Choi, Hyun Jung; Choi, Dongho

    2013-01-01

    .... However, long-term cultures of functional hepatocytes are difficult to establish. To increase the longevity and maintain the differentiated functions of hepatocytes in primary culture, cells can be cultured in a sandwich configuration of collagen...

  13. Outcome of the TURP-TUVP sandwich procedure for minimally ...

    African Journals Online (AJOL)

    shanker

    TURP–TUVP sandwich procedure for the surgical treatment of BPH larger than 40cc in ... volume larger than 40cc had satisfactory patient safety profile and resulted in .... ment, nursing contact time, and duration of catheterization, besides.

  14. Sandwich-like reconstruction of anterior skull base defects

    Institute of Scientific and Technical Information of China (English)

    WANG Zhengmin; WANG Dehui

    2002-01-01

    @@ RESULTS From October, 1984 to October, 1998, 116 patients underwent transcranial or transcranial-facial approach for the resection of malignant or benign aggressive tumor, and sandwich-like repairs were performed for the anterior skull base defect.

  15. Mechanical and vibro-acoustic aspects of composite sandwich cylinders

    NARCIS (Netherlands)

    Yuan, C.

    2013-01-01

    Designing a fuselage involves many considerations such as strength and stability, fatigue, damage tolerance, fire and lightning resistance, thermal and acoustic insulation, production, inspection, maintenance and repair. In the background of the application of composite sandwich structures on the ai

  16. Mechanical and vibro-acoustic aspects of composite sandwich cylinders

    NARCIS (Netherlands)

    Yuan, C.

    2013-01-01

    Designing a fuselage involves many considerations such as strength and stability, fatigue, damage tolerance, fire and lightning resistance, thermal and acoustic insulation, production, inspection, maintenance and repair. In the background of the application of composite sandwich structures on the ai

  17. Observability and Controllability Analysis for Sandwich Systems with Backlash

    Directory of Open Access Journals (Sweden)

    Luo Na

    2015-12-01

    Full Text Available In this paper, an approach to analyze the observability and controllability of sandwich systems with backlash is proposed. In this method, a non-smooth state-space function is used to describe the sandwich systems with backlash which are also non-smooth non-linear systems. Then, a linearization method based on non-smooth optimization is proposed to derive a linearized state-space function to approximate the non-smooth sandwich systems within a bounded region around the equilibrium point that we are interested in. Afterwards, both observability and controllability matrices are constructed and the methods to analyze the observability as well as controllability of sandwich system with backlash are derived. Finally, numerical examples are presented to validate the proposed method.

  18. Mechanical and vibro-acoustic aspects of composite sandwich cylinders

    NARCIS (Netherlands)

    Yuan, C.

    2013-01-01

    Designing a fuselage involves many considerations such as strength and stability, fatigue, damage tolerance, fire and lightning resistance, thermal and acoustic insulation, production, inspection, maintenance and repair. In the background of the application of composite sandwich structures on the

  19. Residual Strength Prediction of Debond Damaged Sandwich Panels

    DEFF Research Database (Denmark)

    Berggreen, Carl Christian

    This presentation concerns theoretical and experimental prediction of crack propagation and residual strength of debond damaged sandwich panels. It is evident that in order to achieve highly optimised structures which are able to operate in a stochastic loading environment, damage tolerance...... propagation and initiation, as these mechanisms are governing for the overall failure load of the structure. Thus, this presentation will describe the development, validation and application of a FEM based numerical model for prediction of residual strength of damaged sandwich panels. The core......, but they are especially relevant for sandwich structures which by nature are highly optimised structures with a high number of possible damage scenarios and consequent failure mechanisms. A major challenge in estimation of structural integrity of damaged sandwich structures is modelling and prediction of crack...

  20. Fracture Characterization of Sandwich Face/Core Interfaces

    DEFF Research Database (Denmark)

    Manca, Marcello

    such result it is important to devise new experimental and analytical techniques to establish the multi-mode fracture characteristics of sandwich plate structures and accordingly develop methods to inhibit defect propagation. This thesis deals with characterization of fracture between face and core...... samples. A number of sandwich materials were tested (GFRP/foam cores and CFRP/Nomex) bothin static and fatigue. A linear elastic fracture mechanics model was used to determine the analyticalexpression of compliance which allowed to calculate automatically the crack length. In combination, a finite element...... types of sandwich samples atdifferent mode mixities and ΔG levels, and results in agreement with previous studies were obtained suggesting that the developed testing method is a reliable tool for the study of face/core interface debonded sandwich structures....

  1. Forced vibration of a shear thickening fluid sandwich beam

    Science.gov (United States)

    Wei, Minghai; Hu, Gang; Jin, Lu; Lin, Kun; Zou, Dujian

    2016-05-01

    The forced vibration of a sandwich beam integrating a shear thickening fluid (STF) core and with conductive skins subjected to a periodic excitation was investigated theoretically in this study. The rheological properties of the STF material including viscosity, plasticity, and elasticity may be changed under the periodic vibration, and hence they were considered. The governing equation of motion was derived based on the complex stiffness method and some key parameters were derived based on the Timoshenko beam theory. Effects of the excitation frequency, the excitation amplitude, the excitation location, and the skin/core thickness ratio on the nature frequency of the sandwich beam were investigated. It was found that the STF core has a significant effect on the dynamic property of the sandwich beam. Based on the findings, integrating the STF core in a sandwich beam can reduce the vibration of the beam.

  2. Dispersion of Lamb waves in a honeycomb composite sandwich panel.

    Science.gov (United States)

    Baid, Harsh; Schaal, Christoph; Samajder, Himadri; Mal, Ajit

    2015-02-01

    Composite materials are increasingly being used in advanced aircraft and aerospace structures. Despite their many advantages, composites are often susceptible to hidden damages that may occur during manufacturing and/or service of the structure. Therefore, safe operation of composite structures requires careful monitoring of the initiation and growth of such defects. Ultrasonic methods using guided waves offer a reliable and cost effective method for defects monitoring in advanced structures due to their long propagation range and their sensitivity to defects in their propagation path. In this paper, some of the useful properties of guided Lamb type waves are investigated, using analytical, numerical and experimental methods, in an effort to provide the knowledge base required for the development of viable structural health monitoring systems for composite structures. The laboratory experiments involve a pitch-catch method in which a pair of movable transducers is placed on the outside surface of the structure for generating and recording the wave signals. The specific cases considered include an aluminum plate, a woven composite laminate and an aluminum honeycomb sandwich panel. The agreement between experimental, numerical and theoretical results are shown to be excellent in certain frequency ranges, providing a guidance for the design of effective inspection systems.

  3. Lightweight Sandwich Panel in Cold Stores and Refrigerated Warehouses

    OpenAIRE

    Chidom, Charles

    2013-01-01

    The use of sandwich panels has gained considerable recognition in the construction industry and more use of this composite structure is ever increasing. This study highlights and familiarizes the use of lightweight sandwich panel in refrigerated warehouses and cold storage facility and construction and the challenges such construction faces in warm climates considering the effects of thermal load. The study was commissioned by HAMK Sheet Metal Center, the steel research and development ce...

  4. Optimization of composite sandwich cover panels subjected to compressive loadings

    Science.gov (United States)

    Cruz, Juan R.

    1991-01-01

    An analysis and design method is presented for the design of composite sandwich cover panels that include the transverse shear effects and damage tolerance considerations. This method is incorporated into a sandwich optimization computer program entitled SANDOP. As a demonstration of its capabilities, SANDOP is used in the present study to design optimized composite sandwich cover panels for for transport aircraft wing applications. The results of this design study indicate that optimized composite sandwich cover panels have approximately the same structural efficiency as stiffened composite cover panels designed to satisfy individual constraints. The results also indicate that inplane stiffness requirements have a large effect on the weight of these composite sandwich cover panels at higher load levels. Increasing the maximum allowable strain and the upper percentage limit of the 0 degree and +/- 45 degree plies can yield significant weight savings. The results show that the structural efficiency of these optimized composite sandwich cover panels is relatively insensitive to changes in core density. Thus, core density should be chosen by criteria other than minimum weight (e.g., damage tolerance, ease of manufacture, etc.).

  5. A study of structurally efficient graphite-thermoplastic trapezoidal-corrugation sandwich and semi-sandwich panels

    Science.gov (United States)

    Jegley, Dawn C.

    1993-01-01

    The structural efficiency of compression-loaded trapezoidal-corrugation sandwich and semi-sandwich composite panels is studied to determine their weight savings potential. Sandwich panels with two identical face sheets and a trapezoidal corrugated core between them, and semi-sandwich panels with a corrugation attached to a single skin are considered. An optimization code is used to find the minimum weight designs for critical compressive load levels ranging from 3,000 to 24,000 lb/in. Graphite-thermoplastic panels based on the optimal minimum weight designs were fabricated and tested. A finite-element analysis of several test specimens was also conducted. The results of the optimization study, the finite-element analysis, and the experiments are presented.

  6. Electronically asymmetric bis(porphyrin) sandwich complexes

    Energy Technology Data Exchange (ETDEWEB)

    Girolami, G.S.; Gorlin, P.A.; Suslick, K.S. [Univ. of Illinois, Urbana, IL (United States)

    1994-02-16

    Bis(porphyrin)metal(IV) complexes (M(porph){sub 2}) have been extensively studies in recent years due to their structural, chemical, and spectroscopic similarity to the {open_quotes}special pair{close_quotes} found in the reaction center of photosynthetic bacteria. Strong interactions arise in the bis(porphyrin) complexes due to the short inter-porphyrin separation (< 3 {angstrom}), which results in properties not seen in mono(porphyrin) analogs. For example, the bis(porphyrin) complexes are considerably easier to oxidize than analogous mono(porphyrin) species, and the M(porph){sub 2{sup n+}} cations (n = 1,2) exhibit near-IR absorptions not found in simple mono(porphyrin)cations. As part of the authors continuing effort to understand the factors that govern the electronic structures of bis(porphyrin) supermolecules, the authors now describe the synthesis of a series of zirconium sandwich complexes. Introduction of electron-withdrawing or -donating groups on the {beta}-pyrrole position considerably affects the electronic properties of these molecules without altering their steric parameters. Thus, peripheral substitution allows modification of the inter-porphyrin {pi} interactions while keeping the inter-porphyrin separation constant. Previous studies have changed the identity of the central metal, but the electronic structure and the interplanar distance could not be varied independently.

  7. 78 FR 37876 - Establishment of Regional Energy Resource Council and Solicitation of Nominations for Membership

    Science.gov (United States)

    2013-06-24

    ... Establishment of Regional Energy Resource Council and Solicitation of Nominations for Membership AGENCY: Tennessee Valley Authority (TVA). ACTION: Notice of Establishment of the Regional Energy Resource Council and Solicitation of Nominations for Membership. SUMMARY: Pursuant to the Tennessee Valley...

  8. 75 FR 15704 - Old Dominion Electric Cooperative; North Carolina Electric Membership Corporation, Complainants v...

    Science.gov (United States)

    2010-03-30

    ... Energy Regulatory Commission Old Dominion Electric Cooperative; North Carolina Electric Membership Corporation, Complainants v. Virginia Electric and Power Company, Respondent; Notice of Complaint March 23...), Old Dominion Electric Cooperative and North Carolina Electric Membership Corporation...

  9. 75 FR 57263 - Solicitation of Nominations for Membership on the Civil Nuclear Trade Advisory Committee

    Science.gov (United States)

    2010-09-20

    ... International Trade Administration Solicitation of Nominations for Membership on the Civil Nuclear Trade Advisory Committee AGENCY: International Trade Administration, DOC. ACTION: Notice. SUMMARY: The Department of Commerce is currently seeking nominations for membership on the Civil Nuclear Trade...

  10. Party member recruitment and the representativeness of party membership

    DEFF Research Database (Denmark)

    Kosiara-Pedersen, Karina

    Party membership figures are in decline. However, parties are still recruiting party members. Are there any differences in the social and political characteristics of old and new party members? If there is a difference, are new party members more or less representative for party voters than old...

  11. 7 CFR 982.30 - Establishment and membership.

    Science.gov (United States)

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling Hazelnut Control Board § 982.30 Establishment and membership. (a) There is hereby established a Hazelnut Marketing Board consisting of 10 members, each of whom shall have...

  12. 7 CFR 1150.131 - Establishment and membership.

    Science.gov (United States)

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE DAIRY PROMOTION PROGRAM Dairy Promotion and Research Order National Dairy Promotion and Research Board § 1150.131 Establishment and membership. (a) There...

  13. 7 CFR 1160.200 - Establishment and membership.

    Science.gov (United States)

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order National Fluid Milk Processor Promotion Board § 1160.200 Establishment and membership. (a)...

  14. The Benefits of FFA Membership as Part of Agricultural Education

    Science.gov (United States)

    Rose, Chelsea; Stephens, Carrie A.; Stripling, Christopher; Cross, Tim; Sanok, Danielle E.; Brawner, Shelby

    2016-01-01

    The study sought to identify the benefits of FFA membership based on the fulfillment of three basic human needs: love and belonging, self-esteem, and self-actualization. The study focused on the fulfillment of FFA members' basic human needs as defined by Abraham Maslow. The three needs on which this study focused are: love and belonging,…

  15. Reconsidering Hispanic Gang Membership and Acculturation in a Multivariate Context

    Science.gov (United States)

    Miller, Holly Ventura; Barnes, J. C.; Hartley, Richard D.

    2011-01-01

    Previous qualitative research has suggested that Hispanic gang membership is linked to the process of acculturation. Specifically, studies have indicated that those who are less assimilated into mainstream American or "Anglo" society are at greater risk for joining gangs. Building on these observations, this study examines the relationship between…

  16. 78 FR 67078 - Membership in a Registered Futures Association

    Science.gov (United States)

    2013-11-08

    ... that while the direct cost of the audit is covered by the annual membership dues, members may incur indirect costs associated with an on-site audit, e.g., preparing for the audit and providing staff to assist NFA staff during the audit. The Commission has authority to ensure all IBs, CTAs, and CPOs...

  17. Cooperative membership and dairy performance among smallholders in Ethiopia

    NARCIS (Netherlands)

    Chagwiza, Clarietta; Muradian, Roldan; Ruben, Ruerd

    2016-01-01

    This study assesses the impact of cooperative membership among dairy producers in Selale, Ethiopia. We selected ten impact indicators: proportion of dairy income to total household income, total dairy income, proportion of crossbreed cows to the total number of cows in the herd (indicator of tech

  18. Cooperative membership and dairy performance among smallholders in Ethiopia

    NARCIS (Netherlands)

    Chagwiza, C.; Muradian Sarache, R.P.; Ruben, R.

    2016-01-01

    This study assesses the impact of cooperative membership among dairy producers in Selale, Ethiopia. We selected ten impact indicators: proportion of dairy income to total household income, total dairy income, proportion of crossbreed cows to the total number of cows in the herd (indicator of technol

  19. 75 FR 52801 - Membership of the Performance Review Board (PRB)

    Science.gov (United States)

    2010-08-27

    ... From the Federal Register Online via the Government Publishing Office ] OFFICE OF THE UNITED STATES TRADE REPRESENTATIVE Membership of the Performance Review Board (PRB) AGENCY: Office of the United... serve on the Performance Review Board: Performance Review Board (PRB) Chair: Florizelle Liser...

  20. 75 FR 60090 - Membership of the Performance Review Board

    Science.gov (United States)

    2010-09-29

    ... Board (PRB) of the Missile Defense Agency (MDA). The publication of PRB membership is required by 5 U.S.... SUPPLEMENTARY INFORMATION: The Performance Review Board (PRB) provides fair and impartial review of Senior... appointed to the Missile Defense Agency PRB: RDML Randall M. Hendrickson, USN (Chair), RADM Joseph A....

  1. 78 FR 34671 - Invitation for Membership on Advisory Committee

    Science.gov (United States)

    2013-06-10

    ... ENROLLMENT OF ACTUARIES Invitation for Membership on Advisory Committee AGENCY: Joint Board for the Enrollment of Actuaries. ACTION: Notice. SUMMARY: The Joint Board for the Enrollment of Actuaries (Joint... Director, Joint Board for the Enrollment of Actuaries; Return Preparer Office SE:RPO; Internal...

  2. 75 FR 53716 - Invitation for Membership on Advisory Committee

    Science.gov (United States)

    2010-09-01

    ...-53717] [FR Doc No: 2010-21609] JOINT BOARD FOR THE ENROLLMENT OF ACTUARIES Invitation for Membership on Advisory Committee AGENCY: Joint Board for the Enrollment of Actuaries. ACTION: Notice. SUMMARY: The Joint Board for the Enrollment of Actuaries (Joint Board), [[Page 53717

  3. 7 CFR 1219.30 - Establishment and membership.

    Science.gov (United States)

    2010-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE HASS AVOCADO PROMOTION, RESEARCH, AND INFORMATION Hass Avocado Promotion, Research, and Information Order The Hass Avocado Board § 1219.30 Establishment and membership. (a) A Hass Avocado Board, called the Board elsewhere in this...

  4. Gang Membership and Drug Involvement: Untangling the Complex Relationship

    Science.gov (United States)

    Bjerregaard, Beth

    2010-01-01

    Previous research has consistently demonstrated a relationship between gang membership and involvement in illegal substances. In addition, researchers have noted that gang members are frequently more heavily involved in drug sales, which often lead to increases in violent behaviors. Most of this research, however, is either cross-sectional or…

  5. Gang Membership as a Risk Factor for Adolescent Violent Victimization

    Science.gov (United States)

    Taylor, Terrance J.; Peterson, Dana; Esbensen, Finn-Aage; Freng, Adrienne

    2007-01-01

    Youth gangs and violence have received substantial scholarly and public attention during the past two decades. While most of the extant research on youth gang members has focused on their offending behaviors, few quantitative studies have been conducted to examine the link between gang membership and violent victimization. The current study uses…

  6. American Art Therapy Association, Inc.: 2013 Membership Survey Report

    Science.gov (United States)

    Elkins, David E.; Deaver, Sarah P.

    2015-01-01

    The American Art Therapy Association (AATA) surveys its members biennially to collect data regarding membership demographics as well as variables concerning the work environment for art therapists. These surveys can provide a detailed description of these characteristics and how they may change over time. This article statistically compares the…

  7. Reconsidering Hispanic Gang Membership and Acculturation in a Multivariate Context

    Science.gov (United States)

    Miller, Holly Ventura; Barnes, J. C.; Hartley, Richard D.

    2011-01-01

    Previous qualitative research has suggested that Hispanic gang membership is linked to the process of acculturation. Specifically, studies have indicated that those who are less assimilated into mainstream American or "Anglo" society are at greater risk for joining gangs. Building on these observations, this study examines the relationship between…

  8. 7 CFR 929.20 - Establishment and membership.

    Science.gov (United States)

    2010-01-01

    ..., processor, handler, or have a financial interest in the production, sales, marketing or distribution of... Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Establishment and membership. (a) There is hereby established a Cranberry Marketing Committee consisting of...

  9. 10 CFR 1042.215 - Membership practices of certain organizations.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Membership practices of certain organizations. 1042.215 Section 1042.215 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) NONDISCRIMINATION ON THE BASIS OF SEX IN EDUCATION PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Coverage § 1042.215...

  10. Multiple team membership : A demand or resource for employees?

    NARCIS (Netherlands)

    Pluut, H.; Flestea, A.M.; Curseu, P.L.

    2014-01-01

    Multiple team membership as a work design feature is becoming more widespread in modern organizations, with expected positive and negative consequences for individual employees. This study explores whether fragmentation of time across multiple teams is a job demand or a job resource for employees.

  11. 7 CFR 927.20 - Establishment and membership.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Establishment and membership. 927.20 Section 927.20 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... districts; (4) Economies to result for growers in promoting efficient administration due to redistricting or...

  12. American Art Therapy Association, Inc.: 2013 Membership Survey Report

    Science.gov (United States)

    Elkins, David E.; Deaver, Sarah P.

    2015-01-01

    The American Art Therapy Association (AATA) surveys its members biennially to collect data regarding membership demographics as well as variables concerning the work environment for art therapists. These surveys can provide a detailed description of these characteristics and how they may change over time. This article statistically compares the…

  13. 75 FR 67696 - Membership of the Performance Review Board

    Science.gov (United States)

    2010-11-03

    ... of the Secretary Membership of the Performance Review Board AGENCY: Defense Finance and Accounting... Performance Review Board (PRB) of the Defense Finance and Accounting Service (DFAS). The publication of PRB...: Denise Thornburg, DFAS SES Program Manager, Defense Finance and Accounting Service, Arlington,...

  14. 7 CFR 946.22 - Establishment and membership.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Establishment and membership. 946.22 Section 946.22 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... in acreage within districts and within the production area during recent years; (2) The importance...

  15. Greek Membership: The Relationship with First-Year Academic Performance

    Science.gov (United States)

    DeBard, Robert; Sacks, Casey

    2012-01-01

    Much has been written about the need for student involvement to build a sense of belonging on college campuses. However, when it comes to membership in Greek social organizations, such involvement has been largely cast as negative. Unlike many of the anecdotal articles critical of the influence joining a Greek social organization can have on…

  16. Schoolyard Corner Society: Relating Membership to Reactive and Proactive Aggressiveness

    Science.gov (United States)

    Storksen, Svein; Idsoe, Thormod; Roland, Erling

    2011-01-01

    This study investigated whether secondary schools in Norway had deviant subcultures, which could be labelled "schoolyard corner society", and how gender and age were related to membership. We also studied levels of reactive and proactive aggressiveness in students, and the relationship between these types of aggressiveness and participation in…

  17. Women otolaryngologist representation in specialty society membership and leadership positions.

    Science.gov (United States)

    Choi, Sukgi S; Miller, Robert H

    2012-11-01

    To determine the proportion of female otolaryngologists in leadership positions relative to their number in the specialty, their membership in various otolaryngology organizations, and age. Cross-sectional analyses of otolaryngology organization membership with a subgroup analysis on female membership and leadership proportion comparing 5-year male/female cohort groups. Information on the number of members and leaders was obtained from various specialty societies by direct communication and from their Web sites between June and December 2010. The number of female and male otolaryngologists and their age distribution in 5-year age groups was obtained from the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS). Statistical analyses were used to determine whether women had proportional membership and leadership representation in various specialty societies. Additionally, female representation in other leadership roles was analyzed using the male/female ratio within the 5-year cohort groups. Female otolaryngologists were found to constitute approximately 11% of practicing otolaryngologists. The American Society of Pediatric Otolaryngology had a higher proportion of female members (22%) compared to five other societies. When the gender composition within each organization was taken into account, female representation in specialty society leadership positions was proportionate to their membership across all societies. When gender and age were considered, women have achieved proportionate representation in each of the specialty societies' leadership positions. There was also proportionate representation of females as program directors, American Board of Otolaryngology directors, Residency Review Committee members, and journal editors/editorial board members. Finally, fewer female chairs or chiefs of departments/divisions were seen, but when age was taken into consideration, this difference was no longer significant. Women have achieved parity in

  18. A general strategy towards encapsulation of nanoparticles in sandwiched graphene sheets and the synergic effect on energy storage.

    Science.gov (United States)

    Wang, Yu; Bai, Yuanjuan; Li, Xiao; Feng, Yangyang; Zhang, Huijuan

    2013-03-04

    A novel and universal approach towards the unique encapsulation of nanoparticles in the sandwiched graphene sheets is presented here. In the method, a low-cost, sustainable and environmentally friendly carbon source, glucose, is firstly applied to yield the high-quality, uniform and coupled graphene sheets in a large scale, and the pre-fabricated hydrated nanosheets act as the sacrificial templates to generate the enveloped metallic nanoparticles. After controllable oxidation or removal of the encapsulated nanoparticles, sandwiched nanocomposite with oxidizes nanoparticles encapsulated in graphene sheets or pure phase of sandwich-like and coupled graphene sheets would be achieved. Moreover, the synergic effect on energy storage via Li-ion batteries is solidly verified in the Co(3)O(4)@graphene nanocomposite. More importantly, the unique structure of the nanoparticles-encapsulated sandwiched graphene sheets will definitely result in additional applications, such as biosensors, supercapacitors and specific catalyses. These results have enriched the family of graphene-based materials and recognized some new graphene derivatives, which will be considerably meaningful in chemistry and materials sciences.

  19. Analysis of Mixed Mode I/II/III Fracture in Foam Core Sandwich Structures Using Imposed Displacement Split Cantilever Beams

    Directory of Open Access Journals (Sweden)

    Rizov V.

    2015-09-01

    Full Text Available Static fracture in foam core sandwich structures under mixed mode I/II/III loading conditions was studied theoretically. In order to generate such loading conditions, a thread guide was used to impose in- plane displacements of the lower crack arm of a sandwich Split Cantilever Beam (SCB. The upper crack arm was loaded by a transverse force. A three-dimensional finite element model of the imposed displacement sandwich SCB configuration was developed. The fracture was studied applying the concepts of linear-elastic fracture mechanics. The strain energy release rate mode components distribution along the crack front was analyzed using the virtual crack closure technique. The influence of the imposed displacement magnitude and the crack length on the fracture was evaluated. The effect of the sandwich core material on the mixed-mode I/II/III fracture was studied. For this purpose, finite element simulations were carried-out assuming that the core is made by different rigid cellular foams. It was found that the strain energy release rate decreases when the foam density increases.

  20. 11 CFR 114.7 - Membership organizations, cooperatives, or corporations without capital stock.

    Science.gov (United States)

    2010-01-01

    ... organizational structure. (j) A membership organization, including a trade association, cooperative, or... 11 Federal Elections 1 2010-01-01 2010-01-01 false Membership organizations, cooperatives, or... CORPORATE AND LABOR ORGANIZATION ACTIVITY § 114.7 Membership organizations, cooperatives, or...

  1. Feasibility study of a SiC sandwich neutron spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jian, E-mail: caepwujian@163.com [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, Sichuan Province (China); Lei, Jiarong, E-mail: jiarong_lei@163.com [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, Sichuan Province (China); Jiang, Yong; Chen, Yu; Rong, Ru; Zou, Dehui; Fan, Xiaoqiang [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, Sichuan Province (China); Chen, Gang; Li, Li; Bai, Song [Nanjing Electronic Devices Institute, Nanjing 210016 (China)

    2013-04-21

    Semiconductor sandwich neutron spectrometers are suitable for in-pile measurements of fast reactor spectra thanks to their compact and relatively simple design. We have assembled and tested a sandwich neutron spectrometer based on 4H-silicon carbide (4H-SiC) Schottky diodes. The SiC diodes detect neutrons via neutron-induced charged particles (tritons and alpha particles) produced by {sup 6}Li(n,α){sup 3}H reaction. {sup 6}LiF neutron converter layers are deposited on the front surface of Schottky diodes by magnetron sputtering. The responses of SiC diodes to charged particles were investigated with an {sup 241}Am alpha source. A sandwich neutron spectrometer was assembled with two SiC Schottky diodes selected based on the charged-particle-response experimental results. The low-energy neutron response of the sandwich spectrometer was measured in the neutron field of the Chinese Fast Burst Reactor-II (CFBR-II). Spectra of alpha particles and tritons from {sup 6}Li(n,α){sup 3}H reaction were obtained with two well-resolved peaks. The energy resolution of the sum spectrum was 8.8%. The primary experimental results confirmed the 4H-SiC sandwich neutron spectrometer's feasibility. -- Highlights: ► Sandwich neutron spectrometer employing 4H-SiC as a detecting material has been developed for the first time. ► {sup 6}LiF neutron converter has been deposited on the surface of 4H-SiC Schottky diode. ► Preliminary testing results obtained with the 4H-SiC sandwich neutron spectrometer are presented.

  2. Monolayer graphene saturable absorber with sandwich structure for ultrafast solid-state laser

    Science.gov (United States)

    Zhu, Hongtong; Zhao, Lina; Liu, Jie; Xu, Shicai; Cai, Wei; Jiang, Shouzhen; Zheng, Lihe; Su, Liangbi; Xu, Jun

    2016-08-01

    The uniform-quality, large-area, monolayer graphene saturable absorber (SA) with sandwich structure was fabricated, tested, and successfully applied for the generation of diode-pumped Yb:Y2SiO5 mode-locked laser. Without extra negative dispersion elements, the shortest pulse with duration of ˜883 fs was obtained at 1042.6 nm with an output power of ˜1 W. These promising experimental results suggested that the low-cost, high-quality graphene SA could potentially be employed in practical, high-power, ultrafast mode-locking laser systems.

  3. Employment of a metal microgrid as a front electrode in a sandwich-structured photodetector.

    Science.gov (United States)

    Zhang, Junying; Cai, Chao; Pan, Feng; Hao, Weichang; Zhang, Weiwei; Wang, Tianmin

    2009-07-01

    A highly UV-transparent metal microgrid was prepared and employed as the front electrode in a sandwich-structured ultraviolet (UV) photodetector using TiO(2) thin film as the semiconductor layer. The photo-generated charger carriers travel a shorter distance before reaching the electrodes in comparison with a photodetector using large-spaced interdigitated metal electrodes (where distance between fingers is several to tens of micrometers) on the surface of the semiconductor film. This photodetector responds to UV light irradiation, and the photocurrent intensity increases linearly with the irradiation intensity below 0.2 mW/cm(2).

  4. Development of an innovative sandwich common bulkhead for cryogenic upper stage propellant tank

    Science.gov (United States)

    Szelinski, B.; Lange, H.; Röttger, C.; Sacher, H.; Weiland, S.; Zell, D.

    2012-12-01

    In the frame of the Future Launcher Preparatory Program (FLPP) investigating advancing technologies for the Next Generation of Launchers (NGL) a number of novel key technologies are presently under development for significantly improving vehicle performance in terms of payload capacity and mission versatility. As a respective ESA guided technology development program, Cryogenic Upper Stage Technologies (CUST) has been launched within FLPP that hosts among others the development of a common bulkhead to separate liquid hydrogen from the liquid oxygen compartment. In this context, MT Aerospace proposed an advanced sandwich design concept which is currently in the development phase reaching for TRL4 under MT Aerospace responsibility. Key components of this sandwich common bulkhead are a specific core material, situated in-between two thin aluminum face sheets, and an innovative thermal decoupling element at the equatorial region. The combination of these elements provides excellent thermal insulation capabilities and mechanical performance at a minimum weight, since mechanical and thermal functions are merged in the same component. This improvement is expressed by substantial performance figures of the proposed concept that include high resistance against reverse pressure, an optimized heat leak and minimized mass, involving the sandwich dome structure and the adjacent interface rings. The development of single sub-technologies, all contributing to maturate the sandwich common bulkhead towards the desired technology readiness level (TRL), is described in the context of the given design constraints as well as technical, functional and programmatic requirements, issued from the stage level. This includes the thermal and mechanical characterization of core materials, manufacturing issues as well as non-destructive testing and the thermal and structural analyses and dimensioning of the complete common bulkhead system. Dedicated TRL assessments in the Ariane 5 Mid

  5. Critical velocity of sandwich cylindrical shell under moving internal pressure

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Critical velocity of an infinite long sandwich shell under moving internal pres-sure is studied using the sandwich shell theory and elastodynamics theory. Propagation of axisymmetric free harmonic waves in the sandwich shell is studied using the sandwich shell theory by considering compressibility and transverse shear deformation of the core, and transverse shear deformation of face sheets. Based on the elastodynamics theory, displacement components expanded by Legendre polynomials, and position-dependent elastic constants and densities are introduced into the equations of motion. Critical ve-locity is the minimum phase velocity on the desperation relation curve obtained by using the two methods. Numerical examples and the finite element (FE) simulations are pre-sented. The results show that the two critical velocities agree well with each other, and two desperation relation curves agree well with each other when the wave number κ is relatively small. However, two limit phase velocities approach to the shear wave velocities of the face sheet and the core respectively when k limits to infinite. The two methods are efficient in the investigation of wave propagation in a sandwich cylindrical shell when κ is relatively small. The critical velocity predicted in the FE simulations agrees with theoretical prediction.

  6. Experimental study on mechanical properties of aircraft honeycomb sandwich structures

    Directory of Open Access Journals (Sweden)

    Talebi Mazraehshahi H.

    2010-06-01

    Full Text Available Mechanical behaviour of sandwich panels under different conditions have been exprimentally studied in this research to increase the knowledge of aircraft sandwich panel structures and facilitate design criteria for aircraft structures. Tests were concentrated on the honeycomb sandwich structures under different loads including flexural, insert shear, flat wise tension and compression loads. Furthermore, effect of core density and face material on mechanical behavior of different samples were investigated and compared with analytical and FEM method. Effects of skin thickness on strength of honycomb sandwhich panels under shear pull out and moments have also been considerd in this study. According to this investigation, insert strength and flexural test under different load conditions is strongly affected by face thickness, but compression and tearoff (falt wise tensile properties of a sandwich panel depends on core material. The study concludes that the correlation between experimental results and the analytical predictions will enable the designer to predict the mechanical behaviour and strength of a sandwich beam; however, applied formula may lead engineers to unreliable results for shear modulus.

  7. Thermal buckling analysis of truss-core sandwich plates

    Institute of Scientific and Technical Information of China (English)

    陈继伟; 刘咏泉; 刘伟; 苏先樾

    2013-01-01

    Truss-core sandwich plates have received much attention in virtue of the high values of strength-to-weight and stiffness-to-weight as well as the great ability of impulse-resistance recently. It is necessary to study the stability of sandwich panels under the influence of the thermal load. However, the sandwich plates are such complex three-dimensional (3D) systems that direct analytical solutions do not exist, and the finite element method (FEM) cannot represent the relationship between structural parameters and mechanical properties well. In this paper, an equivalent homogeneous continuous plate is idealized by obtaining the effective bending and transverse shear stiffness based on the characteristics of periodically distributed unit cells. The first order shear deformation theory for plates is used to derive the stability equation. The buckling temperature of a simply supported sandwich plate is given and verified by the FEM. The effect of related parameters on mechanical properties is investigated. The geometric parameters of the unit cell are optimized to attain the maximum buckling temperature. It is shown that the optimized sandwich plate can improve the resistance to thermal buckling significantly.

  8. Design of sandwich acoustic window for sonar domes

    Institute of Scientific and Technical Information of China (English)

    YU Mengsa; LI Dongsheng; GONG Li; XU Jian

    2005-01-01

    Aimed at the low noise design of sonar dome in ships, a method has been presented for calculating the sonar self noise of a simplified sonar dome consisting of sandwich acoustic window and parallel acoustic cavity, which is excited by stationary random pressure fluctuation of turbulence boundary layer, using temporal and spatial double Fourier transform and wavenumber-frequency spectrum analysis. After numerically analyzing the influence of geometrical and physical parameters of acoustic window on the sonar self noise, the design method and reasonable parameters for sandwich acoustic window are proposed. The results show that the property of low noise induced by acoustic window of sandwich is dominated by the cut-off effect of longitudinal wave and transverse wave propagating in the visco-elastic layer of sandwich as well as the mismatch effect of impedance. If the thickness, density, Young's modulus and damping factor of plates and visco-elastic layer as well as the sound speed of longitudinal wave and transverse wave in the visco-elastic layer are selected reasonably, the maximum noise reduction of sandwich acoustic window is 6.5 dB greater than that of a single glass fiber reinforced plastic plate.

  9. Ham Sandwich with Mayo: A Stronger Conclusion to the Classical Ham Sandwich Theorem

    CERN Document Server

    Elton, John H

    2009-01-01

    The conclusion of the classical ham sandwich theorem of Banach and Steinhaus may be strengthened: there always exists a common bisecting hyperplane that touches each of the sets, that is, intersects the closure of each set. Hence, if the knife is smeared with mayonnaise, a cut can always be made so that it will not only simultaneously bisect each of the ingredients, but it will also spread mayonnaise on each. A discrete analog of this theorem says that n finite nonempty sets in n-dimensional Euclidean space can always be simultaneously bisected by a single hyperplane that contains at least one point in each set. More generally, for n compactly-supported positive finite Borel measures in Euclidean n-space, there is always a hyperplane that bisects each of the measures and intersects the support of each measure.

  10. The French Socialist Party: Membership between Closed and Open Primaries

    Directory of Open Access Journals (Sweden)

    Marino De Luca

    2015-03-01

    Full Text Available For some years now the clamor for democratisation of parties' internal functioning has been spreading across democracies. Among them, France has advanced impressively in the past few years. In 2006, the Socialist Party (PS launched a closed primary to choose the socialist candidate, Ségolène Royal, for the 2007 presidential election. Approaching the 2012 presidential elections, the leftist coalition (PS and PRG launched open primary elections to select its chief-executive candidates, with François Hollande finally emerging as a nominee. In this article, we shall examine how the socialist membership changed during the past three socialist congresses, analysing the outcome of the two above-mentioned primary elections. In particular, we shall observe the Le Mans (2005, Reims (2008 and Toulouse (2012 Congresses, and describe membership, participation, and competitiveness within the PS. The study was based on data collected from an administrative unit, the French départements.

  11. Anti-minority attitudes and Tea Party Movement membership.

    Science.gov (United States)

    Tope, Daniel; Pickett, Justin T; Chiricos, Ted

    2015-05-01

    In 2009, shortly after the election of the United States' first black President, a new protest movement emerged. When some supporters of this new Tea Party Movement (TPM) expressed their ire with race-laden messages various commentators suggested that racism may be a major motive for TPM activism. Accordingly, this study draws on national survey data to examine the extent to which racial attitudes and conservative ideology are associated with self-declared membership in the TPM while controlling for contextual factors that have proven influential in other rightist movement research. Key findings reveal that aside from conservative political ideology, racial resentment is indeed among the strongest predictors of TPM membership. Supplemental analyses explore the extent to which conservatives differ from TPM members. The results show that very conservative individuals and TPM members evince similar attitudes. The findings are discussed in terms of contemporary race relations and the implications for future social movement research. Published by Elsevier Inc.

  12. Effective multicasting algorithm for dynamic membership with delay constraint

    Institute of Scientific and Technical Information of China (English)

    CHEN Lin; XU Zheng-quan

    2006-01-01

    This paper proposes an effective heuristic algorithm for dynamic multicast routing with delay-constrained DDMR.The tree constructed by DDMR has the following characteristics: (1) multicast tree changes with the dynamic memberships; (2)the cost of the tree is as small as possible at each node addition/removal event; (3) all of the path delay meet a fixed delay constraint;(4) minimal perturbation to an existing tree. The proposed algorithm is based on "damage" and "usefulness" concepts proposed in previous work, and has a new parameter bf(Balancing Factor) for judging whether or not to rearrange a tree region when membership changes. Mutation operation in Genetic Algorithm (GA) is also employed to find an attached node for a new adding node.Simulation showed that our algorithm performs well and is better than static heuristic algorithms, in term of cost especially.

  13. UPMASK: unsupervised photometric membership assignment in stellar clusters

    CERN Document Server

    Krone-Martins, A

    2013-01-01

    We develop a method for membership assignment in stellar clusters using only photometry and positions. The method, UPMASK, is aimed to be unsupervised, data driven, model free, and to rely on as few assumptions as possible. It is based on an iterative process, principal component analysis, clustering algorithm, and kernel density estimations. Moreover, it is able to take into account arbitrary error models. An implementation in R was tested on simulated clusters that covered a broad range of ages, masses, distances, reddenings, and also on real data of cluster fields. Running UPMASK on simulations showed that it effectively separates cluster and field populations. The overall spatial structure and distribution of cluster member stars in the colour-magnitude diagram were recovered under a broad variety of conditions. For a set of 360 simulations, the resulting true positive rates (a measurement of purity) and member recovery rates (a measurement of completeness) at the 90% membership probability level reached ...

  14. Memristor Crossbar-based Hardware Implementation of Fuzzy Membership Functions

    CERN Document Server

    Merrikh-Bayat, Farnood

    2010-01-01

    In May 1, 2008, researchers at Hewlett Packard (HP) announced the first physical realization of a fundamental circuit element called memristor that attracted so much interest worldwide. This newly found element can easily be combined with crossbar interconnect technology which this new structure has opened a new field in designing configurable or programmable electronic systems. These systems in return can have applications in signal processing and artificial intelligence. In this paper, based on the simple memristor crossbar structure, we propose new and simple circuits for hardware implementation of fuzzy membership functions. In our proposed circuits, these fuzzy membership functions can have any shapes and resolutions. In addition, these circuits can be used as a basis in the construction of evolutionary systems.

  15. 1/3 SUBHARMONIC SOLUTION OF ELLIPTICAL SANDWICH PLATES

    Institute of Scientific and Technical Information of China (English)

    李银山; 张年梅; 杨桂通

    2003-01-01

    The problem of nonlinear forced oscillations for elliptical sandwich plates is dealtwith. Based on the governing equations expressed in terms of five displacement components,the nonlinear dynamic equation of an elliptical sandwich plate under a harmonic force isderived. A superpositive-iterative harmonic balance ( SIHB ) method is presented for thesteady-state analysis of strongly nonlinear oscillators. In a periodic oscillation, the periodicsolutions can be expressed in the form of basic harmonics and bifurcate harmonics. Thus,an oscillation system which is described as a second order ordinary differential equation,can be expressed as fundamental differential equation with fundamental harmonics andincremental differential equation with derived harmonics. The 1/3 subharnonic solution ofan elliptical sandwich plate is investigated by using the methods of SIHB. The SIHB methodis compared with the numerical integration method. Finally, asymptotical stability of the1/3 subharmonic oscillations is inspected.

  16. Sandwich complex-containing macromolecules: property tunability through versatile synthesis.

    Science.gov (United States)

    Abd-El-Aziz, Alaa S; Agatemor, Christian; Etkin, Nola

    2014-03-01

    Sandwich complexes feature unique properties as the physical and electronic properties of a hydrocarbon ligand or its derivative are integrated into the physical, electronic, magnetic, and optical properties of a metal. Incorporation of these complexes into macromolecules results in intriguing physical, electrical, and optical properties that were hitherto unknown in organic-based macromolecules. These properties are tunable through well-designed synthetic strategies. This review surveys many of the synthetic approaches that have resulted in tuning the properties of sandwich complex-containing macromolecules. While the past two decades have seen an ever-growing number of research publications in this field, gaps remain to be filled. Thus, we expect this review to stimulate research interest towards bridging these gaps, which include the insolubility of some of these macromolecules as well as expanding the scope of the sandwich complexes. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Identification of material properties of sandwich structure with piezoelectric patches

    Directory of Open Access Journals (Sweden)

    Zemčík R.

    2008-11-01

    Full Text Available The work focuses on light-weight sandwich structures made of carbon-epoxy skins and foam core which have unique bending stiffness compared to conventional materials. The skins are manufactured by vacuum autoclave technology from unidirectional prepregs and the sandwich is then glued together. The resulting material properties of the structure usually differ from those provided by manufacturer or even those obtained from experimental tests on separate materials, which makes computational models unreliable. Therefore, the properties are identified using the combination of experimental analysis of the sandwich with attached piezoelectric transducer and corresponding static and modal finite element analyses. Simple mathematical optimization with repetitive finite element solution is used. The model is then verified by transient analysis when the piezoelectric patch is excited by harmonic signals covering the first two eigen-frequencies and the induced oscillations are measured by laser sensor.

  18. Microtomography with sandwich detectors for small-animal bone imaging

    Science.gov (United States)

    Kim, S. H.; Kim, D. W.; Kim, D.; Youn, H.; Cho, S.; Kim, H. K.

    2016-10-01

    An x-ray radiographic system consisting of two detectors in tandem, or a sandwich detector, can produce dual-energy image from a single-shot exposure. Subtraction of two images obtained from the two detectors can produce a sharper image through an unsharp masking effect if the two images are formed at different spatial resolutions. This is indeed possible by incorporating different thicknesses of x-ray conversion layers in the detectors. In this study, we have developed a microtomography system with a sandwich detector in pursuit of high-resolution bone-enhanced small-animal imaging. The results show that the bone-enhanced images reconstructed from the dual-energy projection data provide higher visibility of bone details than the conventionally reconstructed images. The microtomography with the single-shot dual-energy sandwich detector will be useful for the high-resolution bone-enhanced small-animal imaging.

  19. Free vibration Analysis of Sandwich Plates with cutout

    Science.gov (United States)

    Mishra, N.; Basa, B.; Sarangi, S. K.

    2016-09-01

    This paper presents the free vibration analysis of sandwich plates with cutouts. Cutouts are inevitable in structural applications and the presence of these cutouts in the structures greatly influences their dynamic characteristics. A finite element model has been developed here using the ANSYS 15.0 software to study the free vibration characteristics of sandwich plates in the presence of cutouts. Shell 281 element, an 8-noded element with six degrees of freedom suited for analyzing thin to moderately thick structures is considered in the development of the model. Block Lanczose method is adopted to extract the mode shapes to obtain the natural frequency corresponding to free vibration of the plate. The effects of parametric variation on the natural frequency of the sandwich plates with cutout are studied and results are presented.

  20. Enhanced Performance of Sandwich Structures by Improved Damage Tolerance

    DEFF Research Database (Denmark)

    Martakos, Georgios

    The PhD thesis investigates the enhancement of the damage tolerance of sandwich structures by the embedding of a new type of core inserts that act as face/core interface crack stopping elements. The thesis presents series of experimental investigations where the new crack stopping elements...... are embedded in both sandwich beam and panel specimens. The experimental observations form the basis for evaluating the efficiency of the proposed crack stopping inserts. For the experiments, Digital Image Correlation (DIC) was used to characterize the measure the local strain fields and overall deformation...... behaviour around the new crack stopper elements. In support for the experimental investigations, a Finite Element (FE) analysis based methodology, including fracture mechanics analysis and the so-called ‘cycle jump’ technique, was developed to predict the progression of damage in sandwich specimens...

  1. ANALISIS KERAGAAN PANEL SANDWICH UNTUK RUMAH PRA-PABRIKASI

    Directory of Open Access Journals (Sweden)

    Naresworo Nugroho

    2010-12-01

    Full Text Available In the last five years, several earthquakes struck several places in Indonesia and thousands of people died caused of their masonry house. Therefore, the idea of bamboo utilization in the form of structural sandwich panel components for anti-seismic pre-fabrication house is one of appropriate way out. This research describes the performance and behavior of engineered structure wooden-bamboo sandwich panel in full sized test. The wall frame being use were meranti wood, this frame attached by plywood as face and back, then 5 cm bamboo cutting as core; the fastener used in this study were isocyanate resin and nails. This study carried out by experimental data of full scale structural tests on shear wall (ISO 22452. These result showed that the seismic reliability of the wall frame system made of bamboo sandwich panel was appropriate and will be useful for pre-fabrication houses as anti-seismic and environment friendly residential building

  2. Study on voids of epoxy matrix composites sandwich structure parts

    Science.gov (United States)

    He, Simin; Wen, Youyi; Yu, Wenjun; Liu, Hong; Yue, Cheng; Bao, Jing

    2017-03-01

    Void is the most common tiny defect of composite materials. Porosity is closely related to composite structure property. The voids forming behaviour in the composites sandwich structural parts with the carbon fiber reinforced epoxy resin skins was researched by adjusting the manufacturing process parameters. The composites laminate with different porosities were prepared with the different process parameter. The ultrasonic non-destructive measurement method for the porosity was developed and verified through microscopic examination. The analysis results show that compaction pressure during the manufacturing process had influence on the porosity in the laminate area. Increasing the compaction pressure and compaction time will reduce the porosity of the laminates. The bond-line between honeycomb core and carbon fiber reinforced epoxy resin skins were also analyzed through microscopic examination. The mechanical properties of sandwich structure composites were studied. The optimization process parameters and porosity ultrasonic measurement method for composites sandwich structure have been applied to the production of the composite parts.

  3. Examination of Sandwich Materials Using Air-Coupled Ultrasonics

    DEFF Research Database (Denmark)

    Borum, K.K.; Berggreen, Carl Christian

    2004-01-01

    The air-coupled ultrasonic techniques have been improved drastically in recent years. Better equipment has made this technique much more useful. This paper focuses on the examination of sandwich materials used in naval ships. It is more convenient to be able to make the measurements directly...... in atmospheric air instead of using immersion technique. The air-coupled techniques have been used in through-transmission mode using separate sender and receiver transducer. The frequency was either 50 kHz or 120 kHz. Laboratory tests on glass fibre/PVC foam core sandwich panels showed that debonds between core...... and skin laminate could be found by the air-coupled technique. It was therefore decided to use this technique in-situ during mechanical testing of sandwich panels. These tests were done in order to verify a developed FEM code using interfacial fracture mechanics and illustrated on a superstructure...

  4. Effect of layer length on deflection in sandwich beams

    Science.gov (United States)

    Abbu, Muthanna A.; AL-Ameri, Riyadh

    2017-09-01

    A theoretical study has been carried out on sandwich beams strengthened mechanically by two external steel plates attached to their tension and compression sides with so-called "shear connectors ". This study is based on the individual behaviour of each component of the composite sandwich section (i.e. reinforced concrete beam and upper steel plate and lower steel plate). The approach has been developed to simulate the behaviour of such beams, and is based on neglecting the separation between the three layers; i.e., the deflections are equal in each element through the same section. The differential equations reached were solved analytically. Deflection was calculated by using the approach for several beams, tested in two series, and close agreements were obtained with the experimental values. Furthermore, the interaction efficiency between the three elements in a composite sandwich beam has been considered thoroughly, from which the effect of some parameters, such as plate length upon the behaviour of such beams, were studied.

  5. Vibration analysis and optimization of sandwich composite with curvilinear fibers

    Science.gov (United States)

    Honda, S.; Narita, Y.

    2016-09-01

    The present paper develops a shell element based on the refined zigzag theory (RZT) and applies it to the vibration analysis and optimization problem of the composite sandwich plate composed of CFRP skins and soft-cores. The RZT accepts large differences in layer stiffness, and requires less calculation effort than the layer-wise or three-dimensional theories. Numerical results revealed that the present method predicts vibration characteristics of composite sandwich plates with soft-core accurately. Then, shapes of reinforcing fibers in CFRP composite skins are optimized to maximize fundamental frequencies. As an optimizer, the particle swarm optimization (PSO) approach is employed since curvilinear fiber shapes are defined by continuous design variables. Obtained results showed that the composite sandwich with optimum curvilinear fiber shapes indicates higher fundamental frequencies compared with straight fibers.

  6. ['Sandwich PhD': considerations for a successful experience abroad].

    Science.gov (United States)

    Salvetti, Marina de Goes; Bueno, Mariana; Gastaldo, Denise; Kimura, Amélia Fumiko; Pimenta, Cibele Andrucioli de Mattos

    2013-03-01

    International PhD internship, named "Sandwich PhD" in Brazil is an opportunity to improve research abilities, to become known in academic area and to establish and/or increase work opportunities in an international context. In this article, we describe key factors regarding the planning and development of the "Sandwich PhD" as experienced by professors and students involved in the collaboration between the School of Nursing, University of São Paulo and Lawrence S. Bloomberg Faculty of Nursing, University of Toronto, Canada. We also present the participation of PhD students' network as an alternative to the "Sandwich PhD". An international experience, when well-planned and developed correctly, promotes students' personal and professional development and favors the internationalization of Brazilian graduate programs and research groups.

  7. Extended high order sandwich panel theory for bending analysis of sandwich beams with carbon nanotube reinforced face sheets

    Science.gov (United States)

    Jedari Salami, S.

    2016-02-01

    Bending analysis of a sandwich beam with soft core and carbon nanotube reinforced composite (CNTRC) face sheets in the literature is presented based on Extended High order Sandwich Panel Theory (EHSAPT). Distribution of fibers through the thickness of the face sheets could be uniform or functionally graded (FG). In this theory the face sheets follow the first order shear deformation theory (FSDT). Besides, the two dimensional elasticity is used for the core. The field equations are derived via the Ritz based solution which is suitable for any essential boundary condition. The influences of boundary conditions on bending response of the sandwich panel with soft core and CNTRC face sheet are investigated. In each type of boundary condition the effect of distribution pattern of CNTRCs on many essential involved parameters of the sandwich beam with functionally graded carbon nanotube reinforced composite (FG- CNTRC) face sheets are studied in detail. Finally, experimental result have been compared with those obtained based on developed solution method. It is concluded that, the sandwich beam with X distribution figure of face sheets is the strongest with the smallest transverse displacement, and followed by the UD, O and ∧-ones, respectively.

  8. On the perception of religious group membership from faces.

    Directory of Open Access Journals (Sweden)

    Nicholas O Rule

    Full Text Available BACKGROUND: The study of social categorization has largely been confined to examining groups distinguished by perceptually obvious cues. Yet many ecologically important group distinctions are less clear, permitting insights into the general processes involved in person perception. Although religious group membership is thought to be perceptually ambiguous, folk beliefs suggest that Mormons and non-Mormons can be categorized from their appearance. We tested whether Mormons could be distinguished from non-Mormons and investigated the basis for this effect to gain insight to how subtle perceptual cues can support complex social categorizations. METHODOLOGY/PRINCIPAL FINDINGS: Participants categorized Mormons' and non-Mormons' faces or facial features according to their group membership. Individuals could distinguish between the two groups significantly better than chance guessing from their full faces and faces without hair, with eyes and mouth covered, without outer face shape, and inverted 180°; but not from isolated features (i.e., eyes, nose, or mouth. Perceivers' estimations of their accuracy did not match their actual accuracy. Exploration of the remaining features showed that Mormons and non-Mormons significantly differed in perceived health and that these perceptions were related to perceptions of skin quality, as demonstrated in a structural equation model representing the contributions of skin color and skin texture. Other judgments related to health (facial attractiveness, facial symmetry, and structural aspects related to body weight did not differ between the two groups. Perceptions of health were also responsible for differences in perceived spirituality, explaining folk hypotheses that Mormons are distinct because they appear more spiritual than non-Mormons. CONCLUSIONS/SIGNIFICANCE: Subtle markers of group membership can influence how others are perceived and categorized. Perceptions of health from non-obvious and minimal cues

  9. Density Estimation in Several Populations With Uncertain Population Membership

    KAUST Repository

    Ma, Yanyuan

    2011-09-01

    We devise methods to estimate probability density functions of several populations using observations with uncertain population membership, meaning from which population an observation comes is unknown. The probability of an observation being sampled from any given population can be calculated. We develop general estimation procedures and bandwidth selection methods for our setting. We establish large-sample properties and study finite-sample performance using simulation studies. We illustrate our methods with data from a nutrition study.

  10. Efficient Membership Revocation in AC JT Group Signature

    Institute of Scientific and Technical Information of China (English)

    Jing-Liang Zhang; Yu-Min Wang

    2008-01-01

    How to find efficient and secure member ship revocation algorithms is one of the most important issues standing in the way of real-world applications of group signatures. In this paper, the proof of knowledge of divisibility is given and a novel membership revocation method in ACJT group signature scheme is proposed: the group manager issues the product E of the public keys of current members in the group, when a group member wants to sign, he should not only proves that he has a membership certificate, but also proves that the public key in his certificate divides exactly the public key product E with zero knowledge. The proposed method is efficient since the group manager only needs one division and one exponentiation when a group member is deleted, while the signing and verifying procedure are independent of the number of current group members and excluded members, as well as the original group public key and membership certificates needn't be changed.

  11. 用于造船的夹层板构件(SPS)%A new concept for a new age Sandwich Plate System (SPS) for shipbuilding

    Institute of Scientific and Technical Information of China (English)

    黄沛成

    2005-01-01

    The revolutionary Sandwich Plate System (SPS) is superior in every practical way to conventional, stiffened steel plate. A totally new concept in heavy engineering construction, SPS, a steelelastomer-steel structural laminate, is a new-generation building material bringing the shipbuilding and civil engineering industries to the threshold of a new era.

  12. Set membership experimental design for biological systems

    Directory of Open Access Journals (Sweden)

    Marvel Skylar W

    2012-03-01

    Full Text Available Abstract Background Experimental design approaches for biological systems are needed to help conserve the limited resources that are allocated for performing experiments. The assumptions used when assigning probability density functions to characterize uncertainty in biological systems are unwarranted when only a small number of measurements can be obtained. In these situations, the uncertainty in biological systems is more appropriately characterized in a bounded-error context. Additionally, effort must be made to improve the connection between modelers and experimentalists by relating design metrics to biologically relevant information. Bounded-error experimental design approaches that can assess the impact of additional measurements on model uncertainty are needed to identify the most appropriate balance between the collection of data and the availability of resources. Results In this work we develop a bounded-error experimental design framework for nonlinear continuous-time systems when few data measurements are available. This approach leverages many of the recent advances in bounded-error parameter and state estimation methods that use interval analysis to generate parameter sets and state bounds consistent with uncertain data measurements. We devise a novel approach using set-based uncertainty propagation to estimate measurement ranges at candidate time points. We then use these estimated measurements at the candidate time points to evaluate which candidate measurements furthest reduce model uncertainty. A method for quickly combining multiple candidate time points is presented and allows for determining the effect of adding multiple measurements. Biologically relevant metrics are developed and used to predict when new data measurements should be acquired, which system components should be measured and how many additional measurements should be obtained. Conclusions The practicability of our approach is illustrated with a case study. This

  13. Set membership experimental design for biological systems

    Science.gov (United States)

    2012-01-01

    Background Experimental design approaches for biological systems are needed to help conserve the limited resources that are allocated for performing experiments. The assumptions used when assigning probability density functions to characterize uncertainty in biological systems are unwarranted when only a small number of measurements can be obtained. In these situations, the uncertainty in biological systems is more appropriately characterized in a bounded-error context. Additionally, effort must be made to improve the connection between modelers and experimentalists by relating design metrics to biologically relevant information. Bounded-error experimental design approaches that can assess the impact of additional measurements on model uncertainty are needed to identify the most appropriate balance between the collection of data and the availability of resources. Results In this work we develop a bounded-error experimental design framework for nonlinear continuous-time systems when few data measurements are available. This approach leverages many of the recent advances in bounded-error parameter and state estimation methods that use interval analysis to generate parameter sets and state bounds consistent with uncertain data measurements. We devise a novel approach using set-based uncertainty propagation to estimate measurement ranges at candidate time points. We then use these estimated measurements at the candidate time points to evaluate which candidate measurements furthest reduce model uncertainty. A method for quickly combining multiple candidate time points is presented and allows for determining the effect of adding multiple measurements. Biologically relevant metrics are developed and used to predict when new data measurements should be acquired, which system components should be measured and how many additional measurements should be obtained. Conclusions The practicability of our approach is illustrated with a case study. This study shows that our

  14. Methods for Using Durable Adhesively Bonded Joints for Sandwich Structures

    Science.gov (United States)

    Smeltzer, Stanley S., III (Inventor); Lundgren, Eric C. (Inventor)

    2016-01-01

    Systems, methods, and apparatus for increasing durability of adhesively bonded joints in a sandwich structure. Such systems, methods, and apparatus includes an first face sheet and an second face sheet as well as an insert structure, the insert structure having a first insert face sheet, a second insert face sheet, and an insert core material. In addition, sandwich core material is arranged between the first face sheet and the second face sheet. A primary bondline may be coupled to the face sheet(s) and the splice. Further, systems, methods, and apparatus of the present disclosure advantageously reduce the load, provide a redundant path, reduce structural fatigue, and/or increase fatigue life.

  15. NONLINEAR VIBRATION OF CIRCULAR SANDWICH PLATES UNDER CIRCUMJACENT LOAD

    Institute of Scientific and Technical Information of China (English)

    DU Guo-jun; MA Jian-qing

    2006-01-01

    Based on yon Karman plate theory, the issue about nonlinear vibration for circular sandwich plates under circumjacent load with the loosely clamped boundary condition was researched. Nonlinear differential eigenvalue equations and boundary conditions of the problem were formulated by variational method and then their exact static solution can be got. The solution was derived by modified iteration method, so the anslytic relations between amplitude and nonlinear oscillating frequency for circular sandwich plates were obtained. When circumjacent load makes the lowest natural frequency zero,critical load is obtained.

  16. Electronic States in Quasi-one-Dimensional Copolymeric Sandwich Structures

    Institute of Scientific and Technical Information of China (English)

    刘德胜; 王鹿霞; 魏建华; 郑斌; 解士杰; 韩圣浩; 梅良模

    2001-01-01

    The electronic properties of xPA/nPPP/yPA sandwiched copo]ymers with a well-barrier-well structure have been studied by using a tight-binding calculation. It was found that the electronic properties of the neutral states of these sandwiched copolymers are sensitive to the constitutions of PPP and PA monomers and the interface coupling between PA and PPP. It is verified that the quantum tunnelling effect will occur at the lowest conductive state of xPA/nPPP/xPA copolymers.

  17. A New Silicon-Based Ferroelectric Sandwich Structure

    Institute of Scientific and Technical Information of China (English)

    任天令; 张林涛; 刘理天; 李志坚

    2001-01-01

    A new silicon-based PbTiO3/Pb(Zr0.53 Ti0.47)O3/PbTiO3 sandwich structure is fabricated by a sol-gel method. Compared with other fabrication processes without PbTiO3 buffer layers, the annealing temperature is greatly reduced by as much as 100℃. Capacitance-voltage, polarization-electric field and dielectric-frequency properties of this sandwich structure are studied. The Pb(Zrx Ti1-x)O3 films are proved to have good dielectric and ferroelectric properties.

  18. New-sandwiched hydrogen separation membranes with low environmental impact

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Y.; Ozaki, T.; Komaki, M.; Nishimura, C. [Eco-Energy Materials Group, Ecomaterials Center, Ibaraki (Japan)

    2003-07-01

    There is a strong interest in economical methods for hydrogen separation. In this work, we have developed sandwiched membranes, Pd-Ag/V-15Ni/Pd-Ag, which had much lower environmental impact than palladium-based membranes, which are the most commonly used membrane for the current production of highly pure hydrogen. The Pd-Ag overlayer was prepared on V-15Ni substrates (thickness 40 {mu}m) using multi-target sputtering. The hydrogen permeation of the Pd-Ag/V-15Ni/Pd-Ag sandwiched membranes was examined using gas permeation technology. (orig.)

  19. Friction stir welding (FSW of aluminium foam sandwich panels

    Directory of Open Access Journals (Sweden)

    M. Bušić

    2016-07-01

    Full Text Available The article focuses on the influence of welding speed and tool tilt angle upon the mechanical properties at the friction stir welding of aluminium foam sandwich panels. Double side welding was used for producing butt welds of aluminium sandwich panels applying insertion of extruded aluminium profile. Such insertion provided lower pressure of the tool upon the aluminium panels, providing also sufficient volume of the material required for the weldment formation. Ultimate tensile strength and flexural strength for three-point bending test have been determined for samples taken from the welded joints. Results have confirmed anticipated effects of independent variables.

  20. Buckling analysis of sandwich plate using layer wise theory

    Energy Technology Data Exchange (ETDEWEB)

    Ranjbaran, Arash; Khoshravan, Mohammad Reza [University of Tabriz, Tabriz (Iran, Islamic Republic of); Kharazi, Mahsa [Sahand University of Technology, Sahand (Iran, Islamic Republic of)

    2014-07-15

    Buckling analysis of sandwich plate was investigated using layer wise method. The formulation was based on the first-order shear deformation theory, and the Rayleigh-Ritz method was used for approximating and determining the displacement field. The results obtained from layer wise theory was compared with finite element results and showed good agreement. This study demonstrated that layer wise theory could describe buckling behavior of sandwich plates with high accuracy and represents a more realistic and acceptable description of behavior of the plates with much less computational cost.

  1. Damage assessment of compression loaded debond damaged sandwich panels

    DEFF Research Database (Denmark)

    Moslemian, Ramin; Berggreen, Christian; Quispitupa, Amilcar;

    2010-01-01

    Sandwich composites with face sheets of fiber-reinforced plastics (FRP) and cores of polymer foam offer a lightweight construction that is well suited to wind turbine blades, naval and other vessels for high-speed operation or where payload considerations require that the structural weight...... with an implanted circular face/core debond. Compression tests were conducted on intact sandwich panels and panels with an implanted circular face/core debond with three different types of foam core materials (PVC H130, PVC H250 and PMI 51-IG). The strains and out-of-plane displacements of the debonded region were...

  2. Fabrication and characterization of sandwiched optical fibers with periodic gratings.

    Science.gov (United States)

    Chiang, Chia-Chin

    2010-08-01

    This study proposes a novel process for fabricating a sandwiched long-period fiber grating (SLPFG) using a SU-8 thick photoresist technique. The SLPFG consists of a thin cladding optical fiber sandwiched with a double-sided periodical grating coating. By varying the external loads on the SLPFG, the transmission dip of the resonance wavelength is tuned according to a squared-harmonic curve. The SLPFG can thus be utilized as a loss tunable filter or sensor. The resonance dip wavelength is related to the cladding thicknesses of the optical fiber and the periods of the grating. A maximum transmission resonant dip of 34.61dB was achieved.

  3. The effect of sandwiched Ag in the wall of TiO{sub 2} nanotube on the photo-catalytic performance

    Energy Technology Data Exchange (ETDEWEB)

    Liu Zhaohui [Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Chen Jinzhu [Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640 (China); Zhang Yuyuan; Wu Liangpeng [Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Li Xinjun, E-mail: lixj@ms.giec.ac.cn [Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2011-07-15

    Highlights: {yields} TiO{sub 2} nanotube with the wall sandwiched by Ag was prepared. {yields} The sandwiched nanotube structure exhibits enhanced photo-catalytic performance. {yields} Improved photoelectrochemical performance is due to effective charge separation. - Abstract: TiO{sub 2} nanotube was synthesized by a hydrothermal process using TiO{sub 2} nanoparticle as starting material, and then it was loaded with Ag through a silver mirror reaction. Further, the Ag loading TiO{sub 2} nanotube was decorated by TiO{sub 2} via TiCl{sub 4} hydrolysis to obtain the TiO{sub 2} nanotube with the wall sandwiched by Ag. The TiO{sub 2} nanotubes were characterized by transmission electron microscope, energy dispersive X-ray spectroscopy, X-ray diffraction and UV-vis spectrophotometer. The electrochemical impedance spectroscopy and transient photocurrent were investigated in a three-electrode system with the TiO{sub 2} nanotube films served as photoanodes. The photo-catalytic activity was evaluated by photo-degradation of methyl orange under UV light irradiation. The results show that the sandwiched Ag could inhibit the crystal phase transformation of TiO{sub 2} nanotube from anatase to rutile. And the sandwiched nanotube structure exhibits enhanced photo-catalytic performance due to the efficient separation of the photo-generated carriers.

  4. Comparisons of SHM Sensor Models with Empirical Test Data for Sandwich Composite Structures

    Science.gov (United States)

    2011-09-01

    propagation in a honeycomb sandwich panel was done by Metis Design Inc. in collaboration with ARC NASA . The sandwich panel fabricated for this test...structures. Sandwich type composites are being studied for use in NASAs new heavy lift launch vehicle and flaw detection is crucial for safety and for...and at the Marshall Space Flight Center to examine acoustic wave propagating and the ability to detect intrinsic faults in sandwich type composite

  5. Stabilization of nonlinear sandwich systems via state feedback-Discrete-time systems

    NARCIS (Netherlands)

    Wang, Xu; Stoorvogel, Anton A.; Saberi, Ali; Grip, H°avard Fjær; Sannuti, Peddapullaiah

    2011-01-01

    A recent paper (IEEE Trans. Aut. Contr. 2010; 55(9):2156–2160) considered stabilization of a class of continuous-time nonlinear sandwich systems via state feedback. This paper is a discrete-time counterpart of it. The class of nonlinear sandwich systems consists of saturation elements sandwiched bet

  6. A modified DCB sandwich specimen for measuring mixed-mode cohesive laws

    DEFF Research Database (Denmark)

    Lundsgaard-Larsen, Christian; Sørensen, Bent F.; Berggreen, Christian;

    2008-01-01

    A test method is described for measuring cohesive laws for interfaces in sandwich structures. It is proposed to increase the bending stiffness of the sandwich faces by adhering steel bars onto the sandwich faces. This stiffening reduces rotations and ensures that the method is applicable for thin...... which mixed-mode cohesive laws are extracted....

  7. A novel sandwich-type traveling wave piezoelectric tracked mobile system.

    Science.gov (United States)

    Wang, Liang; Shu, Chengyou; Zhang, Quan; Jin, Jiamei

    2017-03-01

    In this paper, a novel sandwich-type traveling wave piezoelectric tracked mobile system was proposed, designed, fabricated and experimentally investigated. The proposed system exhibits the advantages of simple structure, high mechanical integration, lack of electromagnetic interference, and lack of lubrication requirement, and hence shows potential application to robotic rovers for planetary exploration. The tracked mobile system is comprised of a sandwich actuating mechanism and a metal track. The actuating mechanism includes a sandwich piezoelectric transducer and two annular parts symmetrically placed at either end of the transducer, while the metal track is tensioned along the outer surfaces of the annular parts. Traveling waves with the same rotational direction are generated in the two annular parts, producing the microscopic elliptical motions of the surface particles on the annular parts. In this situation, if the pre-load is applied properly, the metal track can be driven by friction force to achieve bidirectional movement. At first, the finite element method was adopted to conduct the modal analysis and harmonic response analysis of the actuating mechanism, and the vibration characteristics were measured to confirm the operating principle. Then the optimal driving frequency of the system prototype, namely 35.1kHz, was measured by frequency sensitivity experiments. At last, the mechanical motion characteristics of the prototype were investigated experimentally. The results show that the average motion speeds of the prototype in dual directions were as 72mm/s and 61.5mm/s under the excitation voltage of 500VRMS, respectively. The optimal loading weights of the prototype in bi-directions were 0.32kg and 0.24kg with a maximum speed of 59.5mm/s and 61.67mm/s at the driving voltage of 300VRMS, respectively.

  8. Relaxed SiGe-on-insulator fabricated by dry oxidation of sandwiched Si/SiGe/Si structure

    Energy Technology Data Exchange (ETDEWEB)

    Di Zengfeng [Research Center of Semiconductor Functional Film Engineering Technology and State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences (CAS), Shanghai 200050 (China); Department of Physics and Material Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Zhang Miao [Research Center of Semiconductor Functional Film Engineering Technology and State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences (CAS), Shanghai 200050 (China); Liu Weili [Research Center of Semiconductor Functional Film Engineering Technology and State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences (CAS), Shanghai 200050 (China); Zhu Ming [Research Center of Semiconductor Functional Film Engineering Technology and State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences (CAS), Shanghai 200050 (China); Department of Physics and Material Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Lin Chenglu [Research Center of Semiconductor Functional Film Engineering Technology and State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences (CAS), Shanghai 200050 (China); Chu, Paul K. [Department of Physics and Material Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China)]. E-mail: paul.chu@cityu.edu.hk

    2005-12-05

    An improved technique is demonstrated to fabricate silicon-germanium on insulator (SGOI) starting with a sandwiched structure of Si/SiGe/Si. After oxidation of the sandwiched structure and successive annealing, a relaxed SiGe-on-insulator (SGOI) structure is produced. Our results indicate that the added Si cap layer is advantageous in suppressing Ge loss at the initial stage of SiGe oxidation and the subsequent annealing process homogenizes the Ge fraction. Raman measurements reveal that the strain in the SiGe layer is fully relaxed at high oxidation temperature ({approx}1150 deg. C) without generating any threading dislocations and crosshatch patterns, which generally exist in the relaxed SiGe layer on bulk Si substrate.

  9. Stiff, Strong Splice For A Composite Sandwich Structure

    Science.gov (United States)

    Schmaling, D.

    1991-01-01

    New type of splice for composite sandwich structure reduces peak shear stress in structure. Layers of alternating fiber orientation interposed between thin ears in adhesive joint. Developed for structural joint in spar of helicopter rotor blade, increases precision of control over thickness of adhesive at joint. Joint easy to make, requires no additional pieces, and adds little weight.

  10. Bending and Deformation of Sandwich Panels Due to Localized Pressure

    Directory of Open Access Journals (Sweden)

    Bambang K. Hadi

    2005-05-01

    Full Text Available Bending and deformation of sandwich panels due to localized pressure were analyzed using both Rayleigh-Ritz and finite element methods. The faces were made of laminated composite plates, while the core was a honeycomb material. Carbon fiber and glass fiber reinforced plastics were used for composite plate faces. In the case of Rayleigh-Ritz method, first the total energy of the system was calculated and then taking the variations of the total energy, the sandwich panel deflections could be computed. The deflections were assumed by means of Fourier series. A finite element code NASTRAN was exploited extensively in the finite element method. 3-dimensional 8-node brick elements were used to model sandwich panels, for both the faces sheets and the core. The results were then compared to each other and in general they are in good agreements. Dimple phenomena were found in these cases. It shows that localized pressure on sandwich structures will produce dimple on the pressurize region with little effects on the rest of the structures.

  11. Mechanical Behavior of CFRP Lattice Core Sandwich Bolted Corner Joints

    Science.gov (United States)

    Zhu, Xiaolei; Liu, Yang; Wang, Yana; Lu, Xiaofeng; Zhu, Lingxue

    2017-02-01

    The lattice core sandwich structures have drawn more attention for the integration of load capacity and multifunctional applications. However, the connection of carbon fibers reinforced polymer composite (CFRP) lattice core sandwich structure hinders its application. In this paper, a typical connection of two lattice core sandwich panels, named as corner joint or L-joint, was investigated by experiment and finite element method (FEM). The mechanical behavior and failure mode of the corner joints were discussed. The results showed that the main deformation pattern and failure mode of the lattice core sandwich bolted corner joints structure were the deformation of metal connector and indentation of the face sheet in the bolt holes. The metal connectors played an important role in bolted corner joints structure. In order to save the calculation resource, a continuum model of pyramid lattice core was used to replace the exact structure. The computation results were consistent with experiment, and the maximum error was 19%. The FEM demonstrated the deflection process of the bolted corner joints structure visually. So the simplified FEM can be used for further analysis of the bolted corner joints structure in engineering.

  12. Electronic transport in nanoparticle monolayers sandwiched between graphene electrodes.

    Science.gov (United States)

    Lu, Chenguang; Zhang, Datong; van der Zande, Arend; Kim, Philip; Herman, Irving P

    2014-11-06

    Graphene/CdSe nanoparticle monolayer/graphene sandwich structures were fabricated to explore the interactions between these layered materials. Electrical transport across these heterostructures suggests that transport is limited by tunneling through the nanoparticle (NP) ligands but not the NP core itself. Photoconductivity suggests ligands may affect the exciton separation efficiency.

  13. Elastic-plastic deformation of sandwich rod on elastic basis

    Institute of Scientific and Technical Information of China (English)

    GU Yu

    2008-01-01

    Sandwich composite material possesses advantages of both light weight and high strength.Although the mechanical behaviors of sandwich composite material with the influence of single external environment have been intensively studied,little work has been done in the study of mechanical property,in view of the nonlinear behavior of sandwich composites in the complicated external environments.In this paper,the problem about the bending of the three-layer elastic-plastic rod located on the elastic base,with a compressibly physical nonlinear core,has been studied.The mechanical response of the designed three-layer elements consisting of two bearing layers and a core has been examined.The complicated problem about curving of the three-layer rod located on the elastic base has been solved.The convergence of the proposed method of elastic solutions is examined to convince that the solution is acceptable.The calculated results indicate that the plasticity and physical nonlinearity of materials have a great influence on the deformation of the sandwich rod on the elastic basis.

  14. Editorial: Sandwiched Between Strasbourg and Karlsruhe: EU Fundamental Rights Protection

    NARCIS (Netherlands)

    Reestman, J.H.; Besselink, L.

    2016-01-01

    Starting out from the notion of the `Verfassungsgerichtsverbund´, coined by the President Vosskuhle of the German Federal Constitutional Court, this contribution sketches the manner in which the European Court of Justice operates, sandwiched in between the European Court of Human Rights that sets a

  15. Electrowetting-driven oscillating drops sandwiched between two substrates

    NARCIS (Netherlands)

    Mampallil, Dileep; Eral, H.B.; Staicu, A.D.; Mugele, F.; Ende, van den D.

    2013-01-01

    Drops sandwiched between two substrates are often found in lab-on-chip devices based on digital microfluidics. We excite azimuthal oscillations of such drops by periodically modulating the contact line via ac electrowetting. By tuning the frequency of the applied voltage, several shape modes can be

  16. Application of Load Carrying Sandwich Elements in Wind Turbine Blades

    DEFF Research Database (Denmark)

    Jensen, Jacob Fisker; Schultz, Jacob Pagh; Berggreen, Carl Christian

    2005-01-01

    . For a single skin design, buckling is critical compared to other design criterions. By introducing sandwich, a significant weight reduction and increased buckling capacity is obtained. Tower clearance now becomes critical. Proper choice of core material and thickness is important to prevent face wrinkling...

  17. Effect of Physical Nonlinearity on Local Buckling in Sandwich Beams

    NARCIS (Netherlands)

    Koissin, Vitaly; Shipsha, Andrey; Skvortsov, Vitaly

    2010-01-01

    This article deals with experimental, theoretical, and FE characterization of the local buckling in foam-core sandwich beams. In the theoretical approach, this phenomena is considered in a periodic formulation (unbounded wrinkle wave); a nonlinear stress—strain response of the face material is accou

  18. Bending moment of galvanized iron glass fiber sandwich panel

    Directory of Open Access Journals (Sweden)

    Gurustal Somnath Swamy

    2016-05-01

    Full Text Available The main objective of this project is to prepare a laminated with Galvanized iron thickness fractions, fiber volume fractions and orientation in the layers of GF were fabricated by hand lay-up method and evaluated for their bending moment properties of the sandwich panel using universal testing machine. This paper theoretically calculates the bending behavior of sandwich panel. The recent need to develop a new range of materials has resulted in the development of high performance lightweight composites with excellent properties. Metal– composite systems consist of alternating layers of metal and fiber-reinforced polymer composites which are bonded by an adhesive. Sandwich beams were tested under Air Bending. Stress-strain and stress-displacement were recorded by using AIMIL UTM. The beam face sheets exhibited a softening non-linearity on the bending side. Experimental results were in good agreement with predictions from simple models. On an overall basis, the sandwich panel exhibited better bending moment performance than the monolithic galvanized iron

  19. The elastic response of sandwich structures to local loading

    NARCIS (Netherlands)

    Koysin, V.; Skvortsov, Vitaly; Krahmalev, Sergey; Shipsha, Andrey

    2004-01-01

    The paper addresses the elastic response of sandwich panels to local static and dynamic loading. The bottom face is assumed to be clamped, so that the overall bending is eliminated. The governing equations are derived using the static Lamé equations for the core and the thin plate Kirchoff–Love

  20. Multiscale Finite-Element Modeling of Sandwich Honeycomb Composite Structures

    Directory of Open Access Journals (Sweden)

    Yu. I. Dimitrienko

    2014-01-01

    Full Text Available The paper presents a developed multi-scale model of sandwich honeycomb structures. The model allows us both to calculate effective elastic-strength characteristics of honeycomb and forced covering of sandwich, and to find a 3D stress-strain state of structures using the threedimensional elastic theory for non- homogeneous media. On the basis of finite element analysis it is shown, that under four-point bending the maximal value of bending and shear stresses in the sandwich honeycomb structures are realized in the zone of applied force and plate support. Here the local stress maxima approximately 2-3 times exceed the “engineering” theoretical plate values of bending and shear stresses in the middle of panel. It is established that at tests for fourpoint bending there is a failure of the honeycomb sandwich panels because of the local adhesion failure rather than because of the covering exfoliation off the honeycomb core in the middle of panel.

  1. Fatigue failure of sandwich beams with face sheet wrinkle defects

    DEFF Research Database (Denmark)

    Leong, Martin Klitgaard; Hvejsel, C.F.; Thomsen, Ole Thybo

    2012-01-01

    This paper presents experimental fatigue results for GFRP face sheet/balsa core sandwich beams with face sheet wrinkle defects, subjected to fully reversed in-plane fatigue loading. An estimate of the fatigue design limit is presented, based on static test results, finite element analyses...

  2. Low-Velocity Impact on Composite Sandwich Plates

    Science.gov (United States)

    1996-07-01

    plate and correct for this error. 3.4 One- and Two-Degree of Freedom Models A single degree of freedom system (figure 3-3a) was used by Caprino et al...Composite Materials, Vol. 26, No. 10: 1523-1535 (1992). 211) Caprino , G., and Teti, R. "Impact and post-impact behavior of foam core sandwich

  3. Fluid Structure Interaction Effect on Sandwich Composite Structures

    Science.gov (United States)

    2011-09-01

    14. SUBJECT TERMS Fluid Structure Interaction, FSI, composite, balsa, low velocity impact, sandwich composites, VARTM , Vacuum Assisted Resin Transfer...11 1. Vacuum Assisted Resin Transfer Molding ( VARTM ) ...................11 2. Procedure...required equipment for VARTM composite production. ..............10 Figure 4. VARTM Lay-up (From [8

  4. Effect of microencapsulated phase change material in sandwich panels

    Energy Technology Data Exchange (ETDEWEB)

    Castellon, Cecilia; Medrano, Marc; Roca, Joan; Cabeza, Luisa F. [GREA Innovacio Concurrent, Edifici CREA, Universitat de Lleida, Pere de Cabrera s/n, 25001 Lleida (Spain); Navarro, Maria E.; Fernandez, Ana I. [Departamento de Ciencias de los Materiales e Ingenieria Metalurgica, Universitat de Barcelona, Marti i Franques 1, 08028 Barcelona (Spain); Lazaro, Ana; Zalba, Belen [Instituto de Investigacion en Ingenieria de Aragon, I3A, Grupo de Ingenieria Termica y Sistemas Energeticos (GITSE), Dpto. Ingenieria Mecanica, Area de Maquinas y Motores Termicos, Universidad de Zaragoza, Campus Politecnico Rio Ebro, Edificio ' ' Agustin de Betancourt,' ' Maria de Luna s/n, 50018 Zaragoza (Spain)

    2010-10-15

    Sandwich panels are a good option as building materials, as they offer excellent characteristics in a modular system. The goal of this study was to demonstrate the feasibility of using the microencapsulated PCM (Micronal BASF) in sandwich panels to increase their thermal inertia and to reduce the energy demand of the final buildings. In this paper, to manufacture the sandwich panel with microencapsulated PCM three different methods were tested. In case 1, the PCM was added mixing the microencapsulated PCM with one of the components of the polyurethane. In the other two cases, the PCM was added either a step before (case 2) or a step after (case 3) to the addition of the polyurethane to the metal sheets. The results show that in case 1 the effect of PCM was overlapped by a possible increase in thermal conductivity, but an increase of thermal inertia was found in case 3. In case 2, different results were obtained due to the poor distribution of the PCM. Some samples showed the effect of the PCM (higher thermal inertia), and other samples results were similar to the conventional sandwich panel. In both cases (2 and 3), it is required to industrialize the process to improve the results. (author)

  5. Dynamic Behaviour of Concrete Sandwich Panel under Blast Loading

    Directory of Open Access Journals (Sweden)

    Dong Yongxiang

    2009-01-01

    Full Text Available Surface contact explosion experiments were performed to study the dynamic behaviour of concrete sandwich panel subjected to blast loading. Experimental results have shown that there are four damage modes explosion cratering, scabbing of the backside, radial cracking induced failure, and circumferential cracking induced failure. It also illustrates that different foam materials sandwiched in the multi-layered medium have an important effect on damage patterns. Due to the foam material, the stress peak decreases one order of magnitude and the duration is more than four times that of the panel without the soft layer by numerical simulation. Additionally, the multi layered medium with concrete foam demonstrates the favourable protective property compared with that of aluminum foam. Meanwhile, the optimal analysis of the thickness of the foam material in the sandwich panel was performed in terms of experimental and numerical analyseis. The proper thickness proportion of soft layer is about 20 percent to the total thickness of sandwich panel under the conditions in this study.Defence Science Journal, 2009, 59(1, pp.22-29, DOI:http://dx.doi.org/10.14429/dsj.59.1480  

  6. Methods for Assessing Honeycomb Sandwich Panel Wrinkling Failures

    Science.gov (United States)

    Zalewski, Bart F.; Dial, William B.; Bednarcyk, Brett A.

    2012-01-01

    Efficient closed-form methods for predicting the facesheet wrinkling failure mode in sandwich panels are assessed. Comparisons were made with finite element model predictions for facesheet wrinkling, and a validated closed-form method was implemented in the HyperSizer structure sizing software.

  7. Flexural Strength of Functionally Graded Nanotube Reinforced Sandwich Spherical Panel

    Science.gov (United States)

    Mahapatra, Trupti R.; Mehar, Kulmani; Panda, Subrata K.; Dewangan, S.; Dash, Sushmita

    2017-02-01

    The flexural behaviour of the functionally graded sandwich spherical panel under uniform thermal environment has been investigated in the present work. The face sheets of the sandwich structure are made by the functionally graded carbon nanotube reinforced material and the core face is made by the isotropic and homogeneous material. The material properties of both the fiber and matrix are assumed to be temperature dependent. The sandwich panel model is developed in the framework of the first order shear deformation theory and the governing equation of motion is derived using the variational principle. For the discretization purpose a suitable shell element has been employed from the ANSYS library and the responses are computed using a parametric design language (APDL) coding. The performance and accuracy of the developed model has been established through the convergence and validation by comparing the obtained results with previously published results. Finally, the influence of different geometrical parameters and material properties on the flexural behaviour of the sandwich spherical panel in thermal environment has been investigated through various numerical illustrations and discussed in details.

  8. Effect of Physical Nonlinearity on Local Buckling in Sandwich Beams

    NARCIS (Netherlands)

    Koysin, V.; Shipsha, Andrey; Skvortsov, Vitaly

    2010-01-01

    This article deals with experimental, theoretical, and FE characterization of the local buckling in foam-core sandwich beams. In the theoretical approach, this phenomena is considered in a periodic formulation (unbounded wrinkle wave); a nonlinear stress—strain response of the face material is accou

  9. Damage tolerance of a composite sandwich with interleaved foam core

    Science.gov (United States)

    Ishai, Ori; Hiel, Clement

    1992-01-01

    A composite sandwich panel consisting of carbon fiber-reinforced plastic (CFRP) skins and a syntactic foam core was selected as an appropriate structural concept for the design of wind tunnel compressor blades. Interleaving of the core with tough interlayers was done to prevent core cracking and to improve damage tolerance of the sandwich. Simply supported sandwich beam specimens were subjected to low-velocity drop-weight impacts as well as high velocity ballistic impacts. The performance of the interleaved core sandwich panels was characterized by localized skin damage and minor cracking of the core. Residual compressive strength (RCS) of the skin, which was derived from flexural test, shows the expected trend of decreasing with increasing size of the damage, impact energy, and velocity. In the case of skin damage, RCS values of around 50 percent of the virgin interleaved reference were obtained at the upper impact energy range. Based on the similarity between low-velocity and ballistic-impact effects, it was concluded that impact energy is the main variable controlling damage and residual strength, where as velocity plays a minor role.

  10. Modular container assembled from fiber reinforced thermoplastic sandwich panels

    Science.gov (United States)

    Donnelly, Mathew William; Kasoff, William Andrew; Mcculloch, Patrick Carl; Williams, Frederick Truman

    2007-12-25

    An improved, load bearing, modular design container structure assembled from thermoformed FRTP sandwich panels in which is utilized the unique core-skin edge configuration of the present invention in consideration of improved load bearing performance, improved useful load volume, reduced manufacturing costs, structural weight savings, impact and damage tolerance and repair and replace issues.

  11. Flexural Behavior of Aluminum Honeycomb Core Sandwich Structure

    Science.gov (United States)

    Matta, Vidyasagar; Kumar, J. Suresh; Venkataraviteja, Duddu; Reddy, Guggulla Bharath Kumar

    2017-05-01

    This project is concerned with the fabrication and flexural testing of aluminium honey comb sandwich structure which is a special case of composite materials that is fabricated by attaching two thin but stiff skins to a light weight but thick core. The core material is normally low density material but its high thickness provide the sandwich composite with high bonding stiffness. Honeycomb core are classified into two types based on the materials and structures. Hexagonal shape has a unique properties i.e has more bonding strength and less formation time based on the cell size and sheet thickness. Sandwich structure exhibit different properties such as high load bearing capacity at low weight and has excellent thermal insulation. By considering the above properties it has tendency to minimize the structural problem. So honey comb sandwich structure is choosed. The core structure has a different applications such as aircraft, ship interiors, construction industries. As there is no proper research on strength characteristics of sandwich structure. So, we use light weight material to desire the strength. There are different parameters involved in this structure i.e cell size, sheet thickness and core height. In this project we considered 3 level of comparison among the 3 different parameters cell size of 4, 6 and 8 mm, sheet thickness of 0.3, 0.5 and 0.7 mm, and core height of 20,25 and 30 mm. In order to reduce the number of experiment we use taguchi design of experiment, and we select the L8 orthogonal array is the best array for this type of situation, which clearly identifies the parameters by independent of material weight to support this we add the minitab software, to identify the main effective plots and regression equation which involves the individual response and corresponding parameters. Aluminium material is used for the fabrication of Honeycomb sandwich structure among the various grades of aluminium we consider the AL6061 which is light weight material

  12. Primary hepatocyte culture in collagen gel mixture and collagen sandwich

    Institute of Scientific and Technical Information of China (English)

    Ying-Jie Wang; Hong-Ling Liu; Hai-Tao Guo; Hong-Wei Wen; Jun Liu

    2004-01-01

    AIM: To explore the methods of hepatocytes culture in a collagen gel mixture or between double layers of collagen sandwich configuration and to examine the functional and cytomorphological characteristics of cultured hepatocytes.METHODS: A two-step collagenase perfusion technique was used to isolate the hepatocytes from Wistar rats or newborn Chinese experimental piglets. The isolated hepatocytes were cultured in a collagen gel mixture or between double layers of collagen sandwich configuration respectively. The former was that rat hepatocytes were mixed with type I rat tail collagen solution till gelled, and the medium was added onto the gel. The latter was that swine hepatocytes were seeded on a plate precoated with collagen gel for 24 h, then another layer of collagen gel was overlaid, resulting in a sandwich configuration. The cytomorphological characteristics, albumin secretion, and LDH-release of the hepatocytes cultured in these two models were examined.RESULTS: Freshly isolated rat hepatocytes were successfully mixed and fixed in collagen gel, and cultured in the gel condition. During the culture period, the urea synthesized and secreted by rat hepatocytes was detected throughout the period. Likewise, newborn experimental piglet hepatocytes were successfully fixed between the double layers of collagen gel, forming a sandwich configuration.Within a week of culture, the albumin secreted by swine hepatocytes was detected by SDS/PAGE analysis. The typical cytomorphological characteristics of the hepatocytes cultured by the above two culture models were found under a phasecontrast microscope. There was little LDH-release during the culture period.CONCLUSION: Both collagen gel mixture and double layers of collagen sandwich configuration can provide cultural conditions much closer to in vivoenvironment, and are helpful for maintaining specific hepatic fiJnctions and cytomorphological characteristics. A collagen gel mixture culture may be more eligible for the

  13. Cascaded-systems analysis of sandwich x-ray detectors

    Science.gov (United States)

    Kim, D. W.; Kim, J.; Yun, S.; Youn, H.; Kim, H. K.

    2016-12-01

    Active sandwich-like multilayer detectors have been developed, and their potential for motion-artifact-free dual-energy x-ray imaging at a single exposure has been demonstrated in the material decomposition context. Since the sandwich detector uses the x-ray beam transmittance through the front layer, direct x-ray interaction within photodiodes in the front layer is unavoidable, and which can increase noise in the front detector images. Similar direct x-ray interaction can also occur in the rear detector layer. To obtain a better contrast performance, an additional filter layer can be placed between the two detector layers. However, this filter layer can increase adversely noise in images obtained from the rear detector layer by reducing the number of x-ray photons reaching it. A theoretical model, which can describe the signal-to-noise performance of the sandwich detector as functions of various design parameters, has been developed by using a linear cascaded-systems theory. From the cascaded-systems analysis, the direct x-ray interaction increases noise at the high spatial frequencies where the number of secondary quanta lessens. The intermediate filter layer enhances the contribution of additive electronic noise in the overall noise performance of the rear detector layer. The detailed cascaded-systems analysis on the x-ray sandwich detectors are reported in comparisons with the measured noise-power spectra and detective quantum efficiencies. The developed model will be useful for a better design and practical use of a sandwich detector for single-shot dual-energy imaging.

  14. Sandwich ELISA for quantitative detection of human collagen prolyl 4-hydroxylase

    Directory of Open Access Journals (Sweden)

    Myllyharju Johanna

    2010-06-01

    Full Text Available Abstract Background We describe a method for specific, quantitative and quick detection of human collagen prolyl 4-hydroxylase (C-P4H, the key enzyme for collagen prolyl-4 hydroxylation, in crude samples based on a sandwich ELISA principle. The method is relevant to active C-P4H level monitoring during recombinant C-P4H and collagen production in different expression systems. The assay proves to be specific for the active C-P4H α2β2 tetramer due to the use of antibodies against its both subunits. Thus in keeping with the method C-P4H is captured by coupled to an anti-α subunit antibody magnetic beads and an anti-β subunit antibody binds to the PDI/β subunit of the protein. Then the following holoenzyme detection is accomplished by a goat anti-rabbit IgG labeled with alkaline phosphatase which AP catalyzes the reaction of a substrate transformation with fluorescent signal generation. Results We applied an experimental design approach for the optimization of the antibody concentrations used in the sandwich ELISA. The assay sensitivity was 0.1 ng of C-P4H. The method was utilized for the analysis of C-P4H accumulation in crude cell extracts of E. coli overexpressing C-P4H. The sandwich ELISA signals obtained demonstrated a very good correlation with the detected protein activity levels measured with the standard radioactive assay. The developed assay was applied to optimize C-P4H production in E. coli Origami in a system where the C-P4H subunits expression acted under control by different promoters. The experiments performed in a shake flask fed-batch system (EnBase® verified earlier observations that cell density and oxygen supply are critical factors for the use of the inducer anhydrotetracycline and thus for the soluble C-P4H yield. Conclusions Here we show an example of sandwich ELISA usage for quantifying multimeric proteins. The method was developed for monitoring the amount of recombinant C-P4H tetramer in crude E. coli extracts. Due

  15. The Planar Sandwich and Other 1D Planar Heat Flow Test Problems in ExactPack

    Energy Technology Data Exchange (ETDEWEB)

    Singleton, Jr., Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-01-24

    This report documents the implementation of several related 1D heat flow problems in the verification package ExactPack [1]. In particular, the planar sandwich class defined in Ref. [2], as well as the classes PlanarSandwichHot, PlanarSandwichHalf, and other generalizations of the planar sandwich problem, are defined and documented here. A rather general treatment of 1D heat flow is presented, whose main results have been implemented in the class Rod1D. All planar sandwich classes are derived from the parent class Rod1D.

  16. Mechanical Response of All-composite Pyramidal Lattice Truss Core Sandwich Structures

    Institute of Scientific and Technical Information of China (English)

    Ming Li; Linzhi Wu; Li Ma; Bing Wang; Zhengxi Guan

    2011-01-01

    The mechanical performance of an all-composite pyramidal lattice truss core sandwich structure was investigated both theoretically and experimentally. Sandwich structures were fabricated with a hot compression molding method using carbon fiber reinforced composite T700/3234. The out-of-plane compression and shear tests were conducted. Experimental results showed that the all-composite pyramidal lattice truss core sandwich structures were more weight efficient than other metallic lattice truss core sandwich structures. Failure modes revealed that node rupture dominated the mechanical behavior of sandwich structures.

  17. Elastic stability of superplastically formed/diffusion-bonded orthogonally corrugated core sandwich plates

    Science.gov (United States)

    Ko, W. L.

    1980-01-01

    The paper concerns the elastic buckling behavior of a newly developed superplastically formed/diffusion-bonded (SPF/DB) orthogonally corrugated core sandwich plate. Uniaxial buckling loads were calculated for this type of sandwich plate with simply supported edges by using orthotropic sandwich plate theory. The buckling behavior of this sandwich plate was then compared with that of an SPF/DB unidirectionally corrugated core sandwich plate under conditions of equal structural density. It was found that the buckling load for the former was considerably higher than that of the latter.

  18. Young Children's Motor Interference Is Influenced by Novel Group Membership.

    Science.gov (United States)

    van Schaik, Johanna E; Endedijk, Hinke M; Stapel, Janny C; Hunnius, Sabine

    2016-01-01

    From early childhood onward, individuals use behavior copying to communicate liking and belonging. This non-verbal signal of affiliation is especially relevant in the context of social groups and indeed both children and adults copy in-group more than out-group members. Given the societal importance of inter-group interactions, it is imperative to understand the mechanistic level at which group modulations of copying occur early in development. The current study was designed to investigate the effect of novel group membership on young children's motor behavior during a simultaneous movement-observation and -execution task. Four- to six-year-olds (n = 65) first gained membership to one of two novel groups based on their color preference and put on a vest in their chosen color. Subsequently, they were instructed to draw a straight line back-and-forth on a tablet computer that was concurrently displaying a stimulus video in which a model moved her arm congruently or incongruently to the child's instructed direction. In half of the stimulus videos the model belonged to the in-group, while in the other half the model belonged to the out-group, as identified by the color of her dress. The deviations into the uninstructed direction of the children's drawings were quantified as a measure of how much observing the models' behaviors interfered with executing their own behaviors. The motor interference effect, namely higher deviations in the incongruent trials than in the congruent trials, was found only for the out-group condition. An additional manipulation of whether the models' arms followed a biological or non-biological velocity profile had little effect on children's motor interference. The results are interpreted in the context of the explicit coordinative nature of the task as an effect of heightened attention toward interacting with an out-group member. This study demonstrates that already during early childhood, novel group membership dynamically influences

  19. Does generalized social trust lead to associational membership? Unraveling a bowl of well-tossed spaghetti

    DEFF Research Database (Denmark)

    Sønderskov, Kim Mannemar

    2011-01-01

    Within the social capital literature it is often assumed that membership of voluntary associations causes generalized social trust and not the other way around. This study challenges this assumption by investigating if generalized social trust causes membership in a novel design that yields valid...... provide rare individual level evidence for a connection between generalized social trust and collective action in that generalized social trust in particular increases membership of associations producing public goods....

  20. Does generalized social trust lead to associational membership? Unraveling a bowl of well-tossed spaghetti

    DEFF Research Database (Denmark)

    Sønderskov, Kim Mannemar

    Within the social capital literature it is often assumed that membership of voluntary associations causes generalized social trust and not the other way around. This study challenges this assumption by investigating if generalized social trust causes membership in a novel design that yields valid....... Moreover, the study provide rare individual level evidence for a connection between generalized social trust and collective action in that generalized social trust in particular increases membership of associations producing public goods....

  1. Handbook of mixed membership models and their applications

    CERN Document Server

    Airoldi, Edoardo M; Erosheva, Elena A; Fienberg, Stephen E

    2014-01-01

    In response to scientific needs for more diverse and structured explanations of statistical data, researchers have discovered how to model individual data points as belonging to multiple groups. Handbook of Mixed Membership Models and Their Applications shows you how to use these flexible modeling tools to uncover hidden patterns in modern high-dimensional multivariate data. It explores the use of the models in various application settings, including survey data, population genetics, text analysis, image processing and annotation, and molecular biology.Through examples using real data sets, yo

  2. Set-Pi: Set Membership pi-Calculus

    DEFF Research Database (Denmark)

    Bruni, Alessandro; Mödersheim, Sebastian Alexander; Nielson, Flemming

    2015-01-01

    Communication protocols often rely on stateful mechanisms to ensure certain security properties. For example, counters and timestamps can be used to ensure authentication, or the security of communication can depend on whether a particular key is registered to a server or it has been revoked. Pro...... from Set-π into Horn clauses that employs the set-membership abstraction to capture the non-monotonicity of the state. Furthermore, we give a characterisation of authentication properties in terms of the set properties in the language, and prove the correctness of our approach. Finally we showcase our...

  3. High-quality sandwiched black phosphorus heterostructure and its quantum oscillations.

    Science.gov (United States)

    Chen, Xiaolong; Wu, Yingying; Wu, Zefei; Han, Yu; Xu, Shuigang; Wang, Lin; Ye, Weiguang; Han, Tianyi; He, Yuheng; Cai, Yuan; Wang, Ning

    2015-06-23

    Two-dimensional materials such as graphene and transition metal dichalcogenides have attracted great attention because of their rich physics and potential applications in next-generation nanoelectronic devices. The family of two-dimensional materials was recently joined by atomically thin black phosphorus which possesses high theoretical mobility and tunable bandgap structure. However, degradation of properties under atmospheric conditions and high-density charge traps in black phosphorus have largely limited its actual mobility thus hindering its future applications. Here, we report the fabrication of stable sandwiched heterostructures by encapsulating atomically thin black phosphorus between hexagonal boron nitride layers to realize ultra-clean interfaces that allow a high field-effect mobility of ∼1,350 cm(2)V(-1) s(-1) at room temperature and on-off ratios exceeding 10(5). At low temperatures, the mobility even reaches ∼2,700 cm(2)V(-1) s(-1) and quantum oscillations in black phosphorus two-dimensional hole gas are observed at low magnetic fields. Importantly, the sandwiched heterostructures ensure that the quality of black phosphorus remains high under ambient conditions.

  4. Spin current valve effect in normal metal/magnetic insulator/normal metal sandwiches

    Science.gov (United States)

    Li, Junxue; Xu, Yadong; Aldosary, Mohammed; Tang, Chi; Lin, Zhisheng; Zhang, Shufeng; Lake, Roger; Shi, Jing; Shines Collaboration

    Pure spin current is generated in two common ways. One makes use of the spin Hall effect in normal metals (NM), the other utilizes spin waves with the quasi-particle excitations called magnons. A popular material for the latter is yttrium iron garnet (YIG), a magnetic insulator (MI). Here we demonstrate in NM/MI/NM sandwiches that these two types of spin current are interconvertible, which allows transmitting an electrical signal across the MI, predicted as the magnon-mediated current drag phenomenon. We show experimentally that the spin current can be switched ``on'' or ``off'' by controlling the magnetization orientation of MI, analogous to conventional spin valves for spin-polarized charge current. The transmitted current drag signal scales linearly with the driving current without any threshold and follows the power-law Tn with n ranging from 1.5 to 2.5. Our results indicate that the NM/MI/NM sandwich structure can serve as a scalable pure spin current valve device which is an essential ingredient in spintronics. As part of the SHINES, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award # SC0012670.

  5. On the assumption of transverse isotropy of a honeycomb sandwich panel for NDT applications

    Science.gov (United States)

    Schaal, Christoph; Tai, Steffen; Mal, Ajit

    2017-04-01

    Due to their excellent strength-to-weight ratio, honeycomb sandwich panels are being increasingly used in lightweight structures, in particular in aircraft and aerospace industry. Delaminations of individual plies in the composite skins or disbonds of a layer in the multi-layer plate structures often remain undetected during visual inspection. Using guided ultrasonic waves, such hidden defects can be detected. For the successful application of ultrasonic nondestructive testing methods, however, wave propagation characteristics have to be well-understood. Recently developed semi-analytical techniques allow for the calculation of dispersion characteristics for many materials. However, the elastic material behavior is often simplified for these calculations. For example, woven composite laminates are modeled as a homogeneous, transversely isotropic plate. While these simplifications only lead to minor errors, the modeling of aluminum honeycomb core sandwich panels with homogeneous, transversely isotropic layers has yet to be validated. In this paper, an efficient numerical approach is used to determine the dispersion characteristics of a honeycomb core layer with and without simplified material behavior. A full 3D-model, including the honeycomb cells, of a small representative volume element of the material is generated using finite elements, and the resulting dispersion curves are compared to the ones obtained from simplified models. In addition to dispersion curves, the displacement fields of the waves are also analyzed.

  6. Interface fatigue crack propagation in sandwich X-joints – Part I: Experiments

    DEFF Research Database (Denmark)

    Moslemian, Ramin; Berggreen, Christian

    2013-01-01

    In this study, face/core fatigue crack growth in sandwich X-joints is investigated numerically and experimentally. The work presented here covers Part I of the study which includes an experimental investigation of fatigue crack growth in sandwich X-joints and characterization of the face/core int......In this study, face/core fatigue crack growth in sandwich X-joints is investigated numerically and experimentally. The work presented here covers Part I of the study which includes an experimental investigation of fatigue crack growth in sandwich X-joints and characterization of the face....../core interface of the joints. Sandwich tear test specimens with a face/core debond representing a debonded sandwich X-joint were tested under cyclic loading. Fatigue tests were conducted on the sandwich tear test specimens with H45, H100 and H250 PVC cores and glass/polyester face sheets. The Digital Image...

  7. Compressive and shear buckling analysis of metal matrix composite sandwich panels under different thermal environments

    Science.gov (United States)

    Ko, William L.; Jackson, Raymond H.

    1993-01-01

    Combined inplane compressive and shear buckling analysis was conducted on flat rectangular sandwich panels using the Raleigh-Ritz minimum energy method with a consideration of transverse shear effect of the sandwich core. The sandwich panels were fabricated with titanium honeycomb core and laminated metal matrix composite face sheets. The results show that slightly slender (along unidirectional compressive loading axis) rectangular sandwich panels have the most desirable stiffness-to-weight ratios for aerospace structural applications; the degradation of buckling strength of sandwich panels with rising temperature is faster in shear than in compression; and the fiber orientation of the face sheets for optimum combined-load buckling strength of sandwich panels is a strong function of both loading condition and panel aspect ratio. Under the same specific weight and panel aspect ratio, a sandwich panel with metal matrix composite face sheets has much higher buckling strength than one having monolithic face sheets.

  8. Outbreak of Salmonella indiana associated with egg mayonnaise sandwiches at an acute NHS hospital.

    Science.gov (United States)

    Mason, B W; Williams, N; Salmon, R L; Lewis, A; Price, J; Johnston, K M; Trott, R M

    2001-12-01

    An outbreak of Salmonella indiana infection in December 2000 affected 17 staff, relatives and patients at an acute NHS Hospital in Swansea. Epidemiological investigation identified egg mayonnaise sandwiches as the vehicle of infection. It was not possible to definitively determine the source of the infection or how the prepared sandwiches became contaminated. The most likely explanation was a pasteurisation failure of a batch of the egg roll used to make these sandwiches. Sandwiches are the most frequently identified vehicle of infection in foodborne outbreaks of salmonella infection in hospitals in England and Wales. The process of sandwich preparation has inherent risks because it involves considerable handling of food, which is consumed without further cooking. Care is required in all stages of preparation including the sourcing of materials used to produce the sandwiches. NHS Trusts should review their Hazard Analysis Critical Control Point plans for sandwich production.

  9. Measuring Multi-Membership in Economic Integration and Its Trade Impact

    DEFF Research Database (Denmark)

    Afesorgbor, Sylvanus Kwaku; van Bergeijk, Peter A.G.

    2014-01-01

    One of the intriguing aspects of African regional trade agreements (RTAs) is the extent of multi-membership, where many African countries are members of more than one RTA. Using a gravity model for 25 countries and the years 1980-2006, we measure the extent of multi-membership and compare its...... a positive impact if an additional membership complements the integration process of the original regional integration initiative: overlapping memberships had a much stronger and significant positive effect on bilateral trade within ECOWAS compare with an insignificant impact within the SADC....

  10. Longitudinal associations between clique membership status and internalizing and externalizing problems during late childhood.

    Science.gov (United States)

    Witvliet, Miranda; van Lier, Pol A C; Brendgen, Mara; Koot, Hans M; Vitaro, Frank

    2010-01-01

    This study examined the longitudinal link between clique membership status and the development of psychopathology in 451 children followed annually from age 9 to 12 years. Classroom clique membership status was identified through social network analysis, and internalizing and externalizing problems were assessed using peer nominations. Controlling for concurrent experiences of social preference and dyadic friendships, a high clique membership probability was found to be related to low levels of internalizing problems and to an increase in externalizing problems across 4 years. This link between clique membership and an increase in externalizing problems was found for boys only.

  11. Measuring Multi-Membership in Economic Integration and Its Trade Impact

    DEFF Research Database (Denmark)

    Afesorgbor, Sylvanus Kwaku; van Bergeijk, Peter A.G.

    2014-01-01

    impact in two major African regional blocs, Economic Community of West Africa States (ECOWAS) and Southern Africa Development Community (SADC). We find that the impact of multi-membership critically depends on the characteristics of the multi-membership of regional integration initiatives. We find...... a positive impact if an additional membership complements the integration process of the original regional integration initiative: overlapping memberships had a much stronger and significant positive effect on bilateral trade within ECOWAS compare with an insignificant impact within the SADC....

  12. Membership Determination of Open Cluster M48 Based on BATC Thirteen-Band Photometry

    CERN Document Server

    Wu, Z Y; Ma, J; Jiang, Z J; Chen, J S; Wu, Zhen-Yu; Zhou, Xu; Ma, Jun; Jiang, Zhao-Ji; Chen, Jian-Sheng

    2006-01-01

    Beijing-Arizona-Taiwan-Connecticut (BATC) multi-band photometric data in the field of open cluster M48 are used to determine its membership. By comparing observed spectral energy distributions (SEDs) of stars with theoretical ones, membership probabilities of 750 stars with limiting magnitude of 15.0 in BATC $c$ band ($\\lambda_{eff}=4194$ \\AA) are determined. 323 stars with membership probabilities higher than 30% are considered as candidate members of M48. Comparing membership probabilities of 229 common stars obtained by the present method and the proper-motion based methods, a 80% agreement among these methods is obtained.

  13. Group membership and social status modulate joint actions.

    Science.gov (United States)

    Aquino, Antonio; Paolini, Daniele; Pagliaro, Stefano; Migliorati, Daniele; Wolff, Annemarie; Alparone, Francesca Romana; Costantini, Marcello

    2015-08-01

    The ability to form shared task representations is considered a keystone of social cognition. It remains, however, contentious if, and to what extent, social categorization impacts on shared representations. In the present study, we address the possibility of the modulation of action co-representation by social categorization, such as group membership and social status, as indexed by the social Simon effect. Italian participants were requested to perform a social Simon task, along with either an Italian (high-status in-group) or an Albanian (low-status out-group) participant. Results show that Italian participants co-represented the action of their partner when paired with a high-status in-group participant. Conversely, this effect was absent when they performed the task with a low-status out-group participant. Furthermore, the Albanian participants co-represented the action of their partner when paired with an Italian participant. These results suggest that group membership modulates action co-representation through the varying of the groups' relative status. The impact of this issue is boundless given the increasing multicultural nature of our society. Indeed, if multiculturalism fails, modern society does likewise.

  14. Development of a double-monoclonal antibody sandwich ELISA: Tool for chicken interferon-γ detection ex vivo

    Science.gov (United States)

    Dai, Hua; Xu, Zheng-zhong; Wang, Meiling; Chen, Jun-hua; Chen, Xiang; Pan, Zhi-ming; Jiao, Xin-an

    2016-01-01

    The aim of the present work was to develop reagents to set up a chicken interferon-γ (ChIFN-γ) assay. Four monoclonal antibodies (mAbs) specific for ChIFN-γ were generated to establish sandwich ELISA based on 2 different mAbs. To improve the detection sensitivity of ChIFN-γ, a double-monoclonal antibody sandwich ELISA was developed using mAb 3E5 as capture antibody and biotinylated mAb 3E3 as a detection reagent. The results revealed that this ELISA has high sensitivity, allowing for the detection of 125 to 500 pg/mL of recombinant ChIFN-γ, and also has an excellent capacity for detecting native ChIFN-γ. This ELISA was then used to detect ChIFN-γ level in chickens immunized with a Newcastle disease virus (NDV) vaccine, the immunized chicken splenocytes were stimulated by NDV F protein as recall antigen. From our results, it appears that the sensitivity range of this sandwich ELISA test is adequate to measure the ex vivo release of ChIFN-γ. PMID:27127340

  15. Ebolavirus nucleoprotein C-termini potently attract single domain antibodies enabling monoclonal affinity reagent sandwich assay (MARSA formulation.

    Directory of Open Access Journals (Sweden)

    Laura J Sherwood

    Full Text Available BACKGROUND: Antigen detection assays can play an important part in environmental surveillance and diagnostics for emerging threats. We are interested in accelerating assay formulation; targeting the agents themselves to bypass requirements for a priori genome information or surrogates. Previously, using in vitro affinity reagent selection on Marburg virus we rapidly established monoclonal affinity reagent sandwich assay (MARSA where one recombinant antibody clone was both captor and tracer for polyvalent nucleoprotein (NP. Hypothesizing that the closely related Ebolavirus genus may share the same Achilles' heel, we redirected the scheme to see whether similar assays could be delivered and began to explore their mechanism. METHODS AND FINDINGS: In parallel we selected panels of llama single domain antibodies (sdAb from a semi-synthetic library against Zaire, Sudan, Ivory Coast, and Reston Ebola viruses. Each could perform as both captor and tracer in the same antigen sandwich capture assay thereby forming MARSAs. All sdAb were specific for NP and those tested required the C-terminal domain for recognition. Several clones were cross-reactive, indicating epitope conservation across the Ebolavirus genus. Analysis of two immune shark sdAb revealed they also targeted the C-terminal domain, and could be similarly employed, yet were less sensitive than a comparable llama sdAb despite stemming from immune selections. CONCLUSIONS: The C-terminal domain of Ebolavirus NP is a strong attractant for antibodies and enables sensitive sandwich immunoassays to be rapidly generated using a single antibody clone. The polyvalent nature of nucleocapsid borne NP and display of the C-terminal region likely serves as a bountiful affinity sink during selections, and a highly avid target for subsequent immunoassay capture. Combined with the high degree of amino acid conservation through 37 years and across wide geographies, this domain makes an ideal handle for monoclonal

  16. Fault Detection of Wind Turbines with Uncertain Parameters: A Set-Membership Approach

    Directory of Open Access Journals (Sweden)

    Thomas Bak

    2012-07-01

    Full Text Available In this paper a set-membership approach for fault detection of a benchmark wind turbine is proposed. The benchmark represents relevant fault scenarios in the control system, including sensor, actuator and system faults. In addition we also consider parameter uncertainties and uncertainties on the torque coefficient. High noise on the wind speed measurement, nonlinearities in the aerodynamic torque and uncertainties on the parameters make fault detection a challenging problem. We use an effective wind speed estimator to reduce the noise on the wind speed measurements. A set-membership approach is used generate a set that contains all states consistent with the past measurements and the given model of the wind turbine including uncertainties and noise. This set represents all possible states the system can be in if not faulty. If the current measurement is not consistent with this set, a fault is detected. For representation of these sets we use zonotopes and for modeling of uncertainties we use matrix zonotopes, which yields a computationally efficient algorithm. The method is applied to the wind turbine benchmark problem without and with uncertainties. The result demonstrates the effectiveness of the proposed method compared to other proposed methods applied to the same problem. An advantage of the proposed method is that there is no need for threshold design, and it does not produce positive false alarms. In the case where uncertainty on the torque lookup table is introduced, some faults are not detectable. Previous research has not addressed this uncertainty. The method proposed here requires equal or less detection time than previous results.

  17. Turkey’s Population Dynamics As A Candidate Country For EU Membership

    Directory of Open Access Journals (Sweden)

    Harun Uçak

    2011-01-01

    Full Text Available Literally, it has been accepted that one of the major obstacles to Turkey’s EU membership is in population term. There has not been any enlargement process as large as Turkey’s population as a single state in EU history before. The enlargement in 2004 which includes 10 states involved 74 million people as whole member states while Turkey’s population is 72 million inhabitants in 2007 data which is only lower than Germany’s population in all EU member states. Thus, Turkey's accession would be different from previous enlargements because of the combined impact of high population. This study compares the population dynamics, working conditions, minimum wage rates and main macroeconomic indicators between Turkey and EU member states. Turkey has young generations compared to EU countries. In the comparison of age groups proportion in total population, 0-19 age group %21,9 in EU 27 and %36,5 in Turkey, 20-39 age group is %28 in EU 27 and %34,3 in Turkey, 40-59 age group is %27,9 in EU and %20,9 in Turkey, 60 and above age group is %22,1 in EU and %9,5 in Turkey. Thus, population dynamics of Turkey could make a contribution to offsetting the ageing of EU 27 societies if the membership would occur in the future. However, minimum wage rates in Turkey are lower than many EU member states but generally higher than EU member states located in Central and Eastern Europe. Thus, immigration possibilities from Turkey can be expected to Western European Countries, but not the same direction to Central and Eastern Europe Countries. Furthermore, the process in macroeconomic indicators will be a determinant in immigration expectations while Turkey’s GDP has been grown faster than EU level recently.

  18. Impact load mitigation in sandwich beams using local resonators

    CERN Document Server

    Sharma, B

    2015-01-01

    Dynamic response of sandwich beams with resonators embedded in the cores subjected to impact loads is studied. Using finite element models the effectiveness of various local resonator frequencies under a given impact load is compared to the behavior of an equivalent mass beam. It is shown that addition of appropriately chosen local resonators into the sandwich beam is an effective method of improving its flexural bending behavior under impact loads. The effect of a given local resonance frequency under different impact load durations is also studied. It is demonstrated that the choice of appropriate local resonance frequency depends on the impact duration. Further, by performing transverse impact experiments, the finite element models are verified and the advantage of using internal resonators under impact loading conditions is demonstrated.

  19. Preserving entanglement under decoherence and sandwiching all separable states

    CERN Document Server

    Lockhart, R B; Lockhart, Robert; Steiner, Michael

    2000-01-01

    Every entangled state can be perturbed, for instance by decoherence, and stay entangled. For a large class of pure entangled states, we show how large the perturbation can be. Our class includes all pure bipartite and all maximally entangled states. For an entangled state, E, the constucted neighborhood of entangled states is the region outside two parallel hyperplanes, which sandwich the set of all separable states. The states for which these neighborhoods are largest are the maximally entangled ones. As the number of particles, or the dimensions of the Hilbert spaces for two of the particles increases, the distance between two of the hyperplanes which sandwich the separable states goes to zero. It is easy to decide if a state Q is in the neighborhood of entangled states we construct for an entangled state E. One merely has to check if the trace of EQ is greater than a constant which depends upon E and which we determine.

  20. Natural fabric sandwich laminate composites: development and investigation

    Indian Academy of Sciences (India)

    C K ARVINDA PANDIAN; H SIDDHI JAILANI; A RAJADURAI

    2017-02-01

    In this work, eco-friendly natural fabric sandwich laminate (NFSL) composites are formulated using jute and linen-fabric-reinforced epoxy with different layer ratios (5:0, 4:1, 3:2, 2:3, 1:4 and 0:5) by hand layup system. Different mechanical attributes (tensile, flexural and impact) of the NFSL composites are quantified. Thermal stability and water absorption behaviour of the NFSL composites are also assessed. A scanning electron microscope (SEM) and optical microscope are used for qualitative analysis of NFSL composites’ interfacial properties. Two layers of jute and three layers of linen sandwich laminate have registered peak values in tensile and impact properties. The five layers of linen laminate composite have exhibited high flexural strength, been proven to have good thermal stability and furthermore shown better water absorption behaviour than any other laminate composites.

  1. Non-linear Behavior of Curved Sandwich Panels

    DEFF Research Database (Denmark)

    Berggreen, Carl Christian; Jolma, P.; Karjalainen, J. P.;

    2003-01-01

    In this paper the non-linear behavior of curved sandwich panels is investigated both numerically and experimentally. Focus is on various aspects of finite element modeling and calculation procedures. A simply supported, singly curved, CFRP/PVC sandwich panel is analyzed under uniform pressure load...... and results are compared to test data. A novel test arrangement utilizing a water filled cushion to create the uniform pressure load on curved panel specimen is used to obtain the experimental data. The panel is modeled with three different commercial finite element codes. Two implicit and one explicit code...... are used with various element types, modeling approaches and material models. The results show that the theoretical and experimental methods generally show fair agreement in panel non-linear behavior before collapse. It is also shown that special attention to detail has to be taken, because the predicted...

  2. Non-Uniform Compressive Strength of Debonded Sandwich Panels

    DEFF Research Database (Denmark)

    Berggreen, Carl Christian; Simonsen, Bo Cerup

    2005-01-01

    This article describes the development, validation and application of a FEM based numerical model for prediction of residual strength of damaged sandwich panels. The core of the theoretical method is a newly developed procedure for prediction of the propagation of a face-core debond. As demonstra......This article describes the development, validation and application of a FEM based numerical model for prediction of residual strength of damaged sandwich panels. The core of the theoretical method is a newly developed procedure for prediction of the propagation of a face-core debond.......(2005)., shows that the model is indeed able to predict the failure modes and the residual strength of damaged panels with accuracy sufficient for practical applications. This opens up for a number of important engineering applications, for example risk-based inspection and repair schemes....

  3. Applications of thin-film sandwich crystallization platforms

    Energy Technology Data Exchange (ETDEWEB)

    Axford, Danny, E-mail: danny.axford@diamond.ac.uk; Aller, Pierre; Sanchez-Weatherby, Juan; Sandy, James [Diamond Light Source, Harwell Oxford, Didcot OX11 0DE (United Kingdom)

    2016-03-24

    Crystallization via sandwiches of thin polymer films is presented and discussed. Examples are shown of protein crystallization in, and data collection from, solutions sandwiched between thin polymer films using vapour-diffusion and batch methods. The crystallization platform is optimal for both visualization and in situ data collection, with the need for traditional harvesting being eliminated. In wells constructed from the thinnest plastic and with a minimum of aqueous liquid, flash-cooling to 100 K is possible without significant ice formation and without any degradation in crystal quality. The approach is simple; it utilizes low-cost consumables but yields high-quality data with minimal sample intervention and, with the very low levels of background X-ray scatter that are observed, is optimal for microcrystals.

  4. Do children trust based on group membership or prior accuracy? The role of novel group membership in children's trust decisions.

    Science.gov (United States)

    Elashi, Fadwa B; Mills, Candice M

    2014-12-01

    Two experiments examined how an informant's group membership can influence children's trust decisions. Participants (3- to 7-year-olds, N=162) were assigned to either the red or blue group based on their selection of a red or blue apron and watched an in-group and out-group informant provide conflicting names for a set of novel objects. When asked which informant they would prefer to rely on for new information, nearly all age groups trusted the in-group informant. Children then watched as each informant varied in accuracy by labeling either all or none of four familiar items accurately and were then asked which informant's labels they preferred for learning new information. When the in-group informant had previously demonstrated accuracy, children continued to trust the in-group informant for new information. In contrast, when the in-group informant had previously demonstrated inaccuracy, children were unsure who to trust, with only 6- and 7-year-olds showing a decrease in their trust for the inaccurate in-group informant. These findings demonstrate that group membership can skew how children encode new information and can make children uncertain about whom to trust for information.

  5. Sandwich-like Reconstruction of Anterior Skull Base Defects

    Institute of Scientific and Technical Information of China (English)

    Wang Zheng-min; Wang De-hui

    2001-01-01

    Objective: To evaluate the safety and efficacy of new modality of anterior skull base repair,namely sandwich-like reconstruction of anterior skull base defects. Methods: A retrospective analysis of patients who underwent transcranial or transcranial-facial resections of malignant or benign aggressive tumors involving the anterior skull base was conducted in our department. We used the sandwich-like reconstruction, using pedicled pericranial flap, frontal muscle flap and free abdominal adipose tissue between them, to separate of cranial cavity and aerodigest tract and keep the frontal lobes in place following resections of anterior skull base tumors. Results: From October, 1984 to October, 1998, 116 patients underwent transcranial or transcranialfacial approach for the resection of malignant or aggressive benign tumor, and sandwich-like repairs were performed for the anterior skull base defect. 54 (46.6 % ) patients had previous operation, with a maximum of 5 surgeries. The average age of patients was 35.9 years old, ranging form 6 to 73 years old. Forty-eight (41.4%)patients had malignant neoplasmas, and sixty-eight (58.6%) patients had benign aggressive tumors. In our series, with the maximal follow-ups for as long as 14 years, NO one had early failure of the one-stage reconstruction. CSF fluid leakage was not encountered, nor was ascending bacterial meningitis observed. No immediate or delayed prolapse of dura or frontal lobes was observed. Conclusion: We conclude that the sandwich-like reconstruction, using pericranial flap, frontal muscle flap and free abdominal adipose between them, is an extremely safe and effective procedure for the repair of skull base defect, even when tumor extensively involves anterior skull base.

  6. Sandwich-like Reconstruction of Anterior Skull Base Defects

    Institute of Scientific and Technical Information of China (English)

    WangZheng-min,MD; WangDe-hui,MD

    2001-01-01

    Objective:To evaluate the safety and efficacy of new modality of anterior skull base repair,namely sandwich-like reconstruction of anterior skull base defects. Methods : A retrospective analysis of patients who underwent wanscranial or wanscranial-facial resections of malignant or benign aggressive tumors involving the anterior skull base was conducted in our department. We used the sandwich-like reconstruction, using pedicled pericranial flap, frontal muscle flap and free abdominal adipose tissue between them, to separate of cranial cavity and aerodigest tract and keep the frontal lobes in place following resections of anterior skull base tumors. Results: From October, 1984 to October, 1998, 116 patients underwent tmnscranial or tmnscranial-facial approach for the resection of malignant or aggressive benign tumor, and sandwich-like repairs were performed for the anterior skull base defect.54 (46.6%) patients had previous operation, with a maximum of 5 surgeries. The average age of patients was 35.9 years old, ranging form 6 to 73 years old. Forty-eight (41.4%) patients had malignant neoplasmas, and sixty-eight (58.6%) patients had benign aggressive tumors. In our series, with the maximal follow-ups for as long as 14 years, NO one had early failure of the one-stage reconstruction. CSF fluid leakage was not encountered, nor was ascending bacterial meningitis observed. No immediate or delayed prolapse of dura or frontal lobes was observed. Conclusion: We conclude that the sandwich-like reconstruction, using pericranial flap, frontal muscle flap and free abdominal adipose between them, is an extremely safe and effective procedure for the repair of skull base defect, even when tumor extensively involves anterior skull base.

  7. Residual Strength of In-plane Loaded Debonded Sandwich Panels

    DEFF Research Database (Denmark)

    Lundsgaard-Larsen, Christian; Nøkkentved, Alexandros; Berggreen, Carl Christian

    2005-01-01

    Face/core debond damaged sandwich panels exposed to uniform and non-uniform compression loads are studied experimentally. The panel geometry is full-scale rectangular with a centrally located circular prefabricated debond. The results show a considerable strength reduction with increasing debond...... diameter, with the failure mechanisms varying between buckling driven debond propagation and face compression failure for large and small debonds respectively....

  8. The Generalized Thin-Sandwich Problem and its Local Solvability

    CERN Document Server

    Giulini, D

    1999-01-01

    We consider Einstein Gravity coupled to dynamical matter consisting of a gauge field with any compact gauge group and minimally coupled scalar fields. We investigate the conditions under which a free specification of a spatial field configuration for the total system and its derivative with respect to coordinate-time determines a solution to the field equations (generalized thin-sandwich problem). Sufficient conditions for local solvability (in the space of fields) are established.

  9. An asymptotically exact theory of smart sandwich shells

    CERN Document Server

    Le, Khanh Chau

    2016-01-01

    An asymptotically exact two-dimensional theory of elastic-piezoceramic sandwich shells is derived by the variational-asymptotic method. The error estimation of the constructed theory is given in the energetic norm. As an application, analytical solution to the problem of forced vibration of a circular elastic plate partially covered by two piezoceramic patches with thickness polarization excited by a harmonic voltage is found.

  10. Flexural Behavior of Two-Way Sandwiched Slabs

    OpenAIRE

    Pachpande, Jivan Vilas

    2015-01-01

    This dissertation presents the details of the findings of a study focused on evaluating the structural behavior of three-dimensional (3D) cementitious sandwich panels with Expanded Polystyrene (EPS) foam core for two-way slab applications. In this study, both theoretical and finite element numerical analysis procedures were adopted to predict the performance of such slabs under out-of-plane loading conditions. The results from theoretical and finite element analysis were verified by compariso...

  11. Graphene Sandwiched Mesostructured Li-Ion Battery Electrodes.

    Science.gov (United States)

    Liu, Jinyun; Zheng, Qiye; Goodman, Matthew D; Zhu, Haoyue; Kim, Jinwoo; Krueger, Neil A; Ning, Hailong; Huang, Xingjiu; Liu, Jinhuai; Terrones, Mauricio; Braun, Paul V

    2016-09-01

    A deterministic graphene-sandwiched Li-ion battery electrode consisting of an integrated 3D mesostructure of electrochemically active materials and graphene is presented. As demonstrations, electrodes with active nanomaterials that coat (V2 O5 @graphene@V2 O5 cathode) or are coated by (graphene@Si@graphene anode) graphene are fabricated. These electrodes exhibit high capacities and ultralong cycle lives (the cathode can be cycled over 2000 times with minimal capacity fade).

  12. Double Rosensweig instability in a ferrofluid sandwich structure

    OpenAIRE

    Rannacher, Dirk; Engel, Andreas

    2003-01-01

    We consider a horizontal ferrofluid layer sandwiched between two layers of immiscible non-magnetic fluids. In a sufficiently strong vertical magnetic field the flat interfaces between magnetic and non-magnetic fluids become unstable to the formation of peaks. We theoretically investigate the interplay between these two instabilities for different combinations of the parameters of the fluids and analyze the evolving interfacial patterns. We also estimate the critical magnetic field strength at...

  13. Two-dimensional analysis of shallow sandwich panels

    DEFF Research Database (Denmark)

    Skvortsov, V; Bozhevolnaya, Elena

    2001-01-01

    The shallow singly curved and rectangular in-plane sandwich panels affected by lateral loads are considered. The set of governing equations on the basis of the Timoshenko-Reissner plate theory is derived for these panels in the case of general boundary conditions. Usage of any real boundary condi...... all four edges and for the panel that is simply supported along its curved boundaries and has hinge-like supports along the straight boundaries. (C) 2001 Elsevier Science Ltd. All rights reserved....

  14. A sandwich ELISA to detect VHSV and IPNV in turbot

    OpenAIRE

    Vázquez-Brañas, M. (Manuel); Coll-Morales, J. (Julio); Estepa, A

    1994-01-01

    Abstract: The recent demonstration that reared turbot (Scophthalmus maximus L) is a natural host for salmonid rhabdoviruses has made their rapid detection relevant to these fish species. A unique protocol to select and use non-competitive monoclonal antibodies (Mabs) for two high-sensitivity sandwich ELISAs has been developed to detect both infectious pancreatic necrosis virus (IPNV) and viral haemorrhagic septicaemia virus (VHSV) in turbot kidney extracts to assess the possibility of using t...

  15. Residual Strength of In-plane Loaded Debonded Sandwich Panels

    DEFF Research Database (Denmark)

    Berggreen, Carl Christian; Simonsen, Bo Cerup

    2005-01-01

    This paper presents a FEM based numerical model for prediction of residual strength of damaged sandwich panels. As demonstrated, the model can predict the maximum load carrying capacity of real-life panels with debond damages, where the failure is governed by face-sheet buckling followed by debond...... growth. Comparison of the theoretical predictions is carried out against a series of largescale experiments described in Lundsgaard-Larsen et al. (2005)...

  16. Sandwich Structured Composites for Aeronautics: Methods of Manufacturing Affecting Some Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Aneta Krzyżak

    2016-01-01

    Full Text Available Sandwich panels are composites which consist of two thin laminate outer skins and lightweight (e.g., honeycomb thick core structure. Owing to the core structure, such composites are distinguished by stiffness. Despite the thickness of the core, sandwich composites are light and have a relatively high flexural strength. These composites have a spatial structure, which affects good thermal insulator properties. Sandwich panels are used in aeronautics, road vehicles, ships, and civil engineering. The mechanical properties of these composites are directly dependent on the properties of sandwich components and method of manufacturing. The paper presents some aspects of technology and its influence on mechanical properties of sandwich structure polymer composites. The sandwiches described in the paper were made by three different methods: hand lay-up, press method, and autoclave use. The samples of sandwiches were tested for failure caused by impact load. Sandwiches prepared in the same way were used for structural analysis of adhesive layer between panels and core. The results of research showed that the method of manufacturing, more precisely the pressure while forming sandwich panels, influences some mechanical properties of sandwich structured polymer composites such as flexural strength, impact strength, and compressive strength.

  17. Impact properties of aluminium - glass fiber reinforced plastics sandwich panels

    Directory of Open Access Journals (Sweden)

    Mathivanan Periasamy

    2012-06-01

    Full Text Available Aluminium - glass fiber reinforced plastics (GFRP sandwich panels are hybrid laminates consisting of GFRP bonded with thin aluminum sheets on either side. Such sandwich materials are increasingly used in airplane and automobile structures. Laminates with varying aluminium thickness fractions, fiber volume fractions and orientation in the layers of GFRP were fabricated by hand lay up method and evaluated for their impact performance by conducting drop weight tests under low velocity impacts. The impact energy required for initiating a crack in the outer aluminium layer as well as the energy required for perforation was recorded. The impact load-time history was also recorded to understand the failure behavior. The damage depth and the damage area were measured to evaluate the impact resistance. Optical photography and scanning electron micrographs were taken to visualize the crack and the damage zone. The bidirectional cross-ply hybrid laminate (CPHL has been found to exhibit better impact performance and damage resistance than the unidirectional hybrid laminate (UDHL. Increase in aluminium thickness fraction (Al tf and fiber volume fraction (Vf resulted in an increase in the impact energy required for cracking and perforation. On an overall basis, the sandwich panels exhibited better impact performance than the monolithic aluminium.

  18. Sandwiched Rényi divergence satisfies data processing inequality

    Energy Technology Data Exchange (ETDEWEB)

    Beigi, Salman [School of Mathematics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5746, Tehran (Iran, Islamic Republic of)

    2013-12-15

    Sandwiched (quantum) α-Rényi divergence has been recently defined in the independent works of Wilde et al. [“Strong converse for the classical capacity of entanglement-breaking channels,” preprint http://arxiv.org/abs/arXiv:1306.1586 (2013)] and Müller-Lennert et al. [“On quantum Rényi entropies: a new definition, some properties and several conjectures,” preprint http://arxiv.org/abs/arXiv:1306.3142v1 (2013)]. This new quantum divergence has already found applications in quantum information theory. Here we further investigate properties of this new quantum divergence. In particular, we show that sandwiched α-Rényi divergence satisfies the data processing inequality for all values of α > 1. Moreover we prove that α-Holevo information, a variant of Holevo information defined in terms of sandwiched α-Rényi divergence, is super-additive. Our results are based on Hölder's inequality, the Riesz-Thorin theorem and ideas from the theory of complex interpolation. We also employ Sion's minimax theorem.

  19. Static and Fatigue Characterization of Nomex Honeycomb Sandwich Panels

    Directory of Open Access Journals (Sweden)

    Keskes Boualem

    2013-07-01

    Full Text Available The main benefits of using the sandwich concept in structural components are the high stiffness, good fatigue resistance and low weight ratios. Recent advances in materials and construction techniques have resulted in further improvement and increased uniformity of the sandwich composite properties. In order to use these materials in different applications, the knowledge of simply their static properties alone is not sufficient but additional information on their fatigue properties and durability are required. In this paper, first static and fatigue tests on four points bending of nomex honeycomb composite sandwich panels have been performed. Load/displacement and S-N fatigue curves are presented and analysed. Fatigue failure and damage modes are observed with an optical microscope and are discussed. The second is to address such fatigue behaviour by using a damage model and check it by experimentation. This fatigue damage model is based on stiffness degradation, which is used as a damage indicator. Two non-linear cumulative damage models derived from the chosen stiffness degradation equation are examined with assumption of linear Miner's damage summation. Predicted results are compared with available experimental data.

  20. Structural modeling of sandwich structures with lightweight cellular cores

    Science.gov (United States)

    Liu, T.; Deng, Z. C.; Lu, T. J.

    2007-10-01

    An effective single layered finite element (FE) computational model is proposed to predict the structural behavior of lightweight sandwich panels having two dimensional (2D) prismatic or three dimensional (3D) truss cores. Three different types of cellular core topology are considered: pyramidal truss core (3D), Kagome truss core (3D) and corrugated core (2D), representing three kinds of material anisotropy: orthotropic, monoclinic and general anisotropic. A homogenization technique is developed to obtain the homogenized macroscopic stiffness properties of the cellular core. In comparison with the results obtained by using detailed FE model, the single layered computational model can give acceptable predictions for both the static and dynamic behaviors of orthotropic truss core sandwich panels. However, for non-orthotropic 3D truss cores, the predictions are not so well. For both static and dynamic behaviors of a 2D corrugated core sandwich panel, the predictions derived by the single layered computational model is generally acceptable when the size of the unit cell varies within a certain range, with the predictions for moderately strong or strong corrugated cores more accurate than those for weak cores.

  1. Size Effects in Impact Damage of Composite Sandwich Panels

    Science.gov (United States)

    Dobyns, Alan; Jackson, Wade

    2003-01-01

    Panel size has a large effect on the impact response and resultant damage level of honeycomb sandwich panels. It has been observed during impact testing that panels of the same design but different panel sizes will show large differences in damage when impacted with the same impact energy. To study this effect, a test program was conducted with instrumented impact testing of three different sizes of sandwich panels to obtain data on panel response and residual damage. In concert with the test program. a closed form analysis method was developed that incorporates the effects of damage on the impact response. This analysis method will predict both the impact response and the residual damage of a simply-supported sandwich panel impacted at any position on the panel. The damage is incorporated by the use of an experimental load-indentation curve obtained for the face-sheet/honeycomb and indentor combination under study. This curve inherently includes the damage response and can be obtained quasi-statically from a rigidly-backed specimen or a specimen with any support conditions. Good correlation has been obtained between the test data and the analysis results for the maximum force and residual indentation. The predictions can be improved by using a dynamic indentation curve. Analyses have also been done using the MSC/DYTRAN finite element code.

  2. Microtomography with a sandwich detector for mouse bone imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Ho; Kim, Junwoo; Kim, Ho Kyung [Pusan National University, Busan (Korea, Republic of); Youn, Hanbean; Jeon, Hosang [Pusan National University Yangsan Hospital, Yangsan (Korea, Republic of)

    2015-10-15

    Single-shot dual-energy imaging, using sandwich detector, the rear detector usually uses a thicker x-ray converter to enhance quantum efficiency with the higher-energy spectrum, hence providing a blurrier image than the front detector. The weighted logarithmic subtraction of the two images therefore results in a form of unsharp masking that enhances edges in the resultant image. Inspired by this observation, we have developed a micro computed tomography (micro-CT) system with the sandwich detector for high-resolution bone imaging of small animals. The sandwich detector consists of two flat-panel detectors by stacking one upon the other. Although the x-ray beam continuously irradiates, the step-rotation of an object and stay-readout of projection data were considered for the scanning and data gathering. It will be necessary that more elaborate experiments with the mouse and/or other quantitative phantoms. And quantification of the image quality of bone-enhanced images in comparisons with the conventional images will be performed. The image analysis of differences between bone-enhanced images obtained from the projection- and image-based approaches can be performed.

  3. Static and Fatigue Characterization of Nomex Honeycomb Sandwich Panels

    Directory of Open Access Journals (Sweden)

    Keskes Boualem

    2013-07-01

    Full Text Available The main benefits of using the sandwich concept in structural components are the high stiffness, good fatigue resistance and low weight ratios. Recent advances in materials and construction techniques have resulted in further improvement and increased uniformity of the sandwich composite properties. In order to use these materials in different applications, the knowledge of simply their static properties alone is not sufficient but additional information on their fatigue properties and durability are required. In this paper, first static and fatigue tests on four points bending of nomex honeycomb composite sandwich panels have been performed. Load/displacement and S-N fatigue curves are presented and analysed. Fatigue failure and damage modes are observed with an optical microscope and are discussed. The second is to address such fatigue behaviour by using a damage model and check it by experimentation. This fatigue damage model is based on stiffness degradation, which is used as a damage indicator. Two non-linear cumulative damage models derived from the chosen stiffness degradation equation are examined with assumption of linear Miner's damage summation. Predicted results are compared with available experimental data.

  4. Structural modeling of sandwich structures with lightweight cellular cores

    Institute of Scientific and Technical Information of China (English)

    T. Liu; Z. C. Deng; T. J. Lu

    2007-01-01

    An effective single layered finite element (FE) computational model is proposed to predict the structural behavior of lightweight sandwich panels having two dimensional (2D) prismatic or three dimensional (3D) truss cores.Three different types of cellular core topology are considered: pyramidal truss core (3D), Kagome truss core (3D) and corrugated core (2D), representing three kinds of material anisotropy: orthotropic, monoclinic and general anisotropic. A homogenization technique is developed to obtain the homogenized macroscopic stiffness properties of the cellular core. In comparison with the results obtained by using detailed FE model, the single layered computational model cangive acceptable predictions for both the static and dynamic behaviors of orthotropic truss core sandwich panels. However, for non-orthotropic 3D truss cores, the predictions are not so well. For both static and dynamic behaviors of a 2D corrugated core sandwich panel, the predictions derived by the single layered computational model is generally acceptable when the size of the unit cell varies within a certain range, with the predictions for moderately strong or strong corrugated cores more accurate than those for weak cores.

  5. Understanding Gang Membership and Crime Victimization among Jail Inmates: Testing the Effects of Self-Control

    Science.gov (United States)

    Fox, Kathleen A.; Lane, Jodi; Akers, Ronald L.

    2013-01-01

    Although previous research has examined factors related to gang membership and offending, research on the relationship between gangs and victimization is limited. The present study builds on previous research and examines gang membership, victimization, and self-control among 2,414 jail inmates. Results from self-report surveys indicate that gang…

  6. Change and stability in childhood clique membership, isolation from cliques, and associated child characteristics

    NARCIS (Netherlands)

    Witvliet, M.; Lier, van P.A.C.; Cuijpers, P.; Koot, H.M.

    2010-01-01

    This study explored the role of clique membership and clique isolation in children’s psychosocial adjustment. We identified change and stability in early elementary school clique membership and investigated behavioral characteristics related to this change and stability. Participants were first-grad

  7. 78 FR 13460 - Chartering and Field of Membership Manual for Federal Credit Unions

    Science.gov (United States)

    2013-02-28

    ... ADMINISTRATION 12 CFR Part 701 RIN 3133-AE02 Chartering and Field of Membership Manual for Federal Credit Unions...) is amending the definition of ``rural district'' in NCUA's Chartering and Field of Membership Manual... which the majority of the district is located. As revised by the final rule, NCUA's Chartering and Field...

  8. 12 CFR 701.1 - Federal credit union chartering, field of membership modifications, and conversions.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Federal credit union chartering, field of... Federal credit union chartering, field of membership modifications, and conversions. National Credit Union Administration policies concerning chartering, field of membership modifications, and conversions are set forth...

  9. 75 FR 6151 - Chartering and Field of Membership for Federal Credit Unions

    Science.gov (United States)

    2010-02-08

    ... ADMINISTRATION 12 CFR Part 701 RIN 3133-AD65 Chartering and Field of Membership for Federal Credit Unions AGENCY... December 17, 2009, the NCUA Board issued a proposed rule amending its chartering and field of membership manual to update its community chartering policies and define the terms ``rural district'' and ``in...

  10. I want to join the zoo! A conjoint study of membership program preferences

    Science.gov (United States)

    David B. Klenosky; Chi-Ok Oh; Christopher C. Panek; Jerry F. Luebke

    2009-01-01

    Membership programs are an important and often vital element for the success and economic sustainability of leisure and tourism visitor attractions. Unfortunately, very little research is available to guide membership program development and promotion efforts. To address this gap in the research literature, a research project assessed member and nonmember preferences...

  11. Incorporating Student Mobility in Achievement Growth Modeling: A Cross-Classified Multiple Membership Growth Curve Model

    Science.gov (United States)

    Grady, Matthew W.; Beretvas, S. Natasha

    2010-01-01

    Multiple membership random effects models (MMREMs) have been developed for use in situations where individuals are members of multiple higher level organizational units. Despite their availability and the frequency with which multiple membership structures are encountered, no studies have extended the MMREM approach to hierarchical growth curve…

  12. Solutions of Multi Objective Fuzzy Transportation Problems with Non-Linear Membership Functions

    Directory of Open Access Journals (Sweden)

    Dr. M. S. Annie Christi

    2016-11-01

    Full Text Available Multi-objective transportation problem with fuzzy interval numbers are considered. The solution of linear MOTP is obtained by using non-linear membership functions. The optimal compromise solution obtained is compared with the solution got by using a linear membership function. Some numerical examples are presented to illustrate this.

  13. Understanding Gang Membership and Crime Victimization among Jail Inmates: Testing the Effects of Self-Control

    Science.gov (United States)

    Fox, Kathleen A.; Lane, Jodi; Akers, Ronald L.

    2013-01-01

    Although previous research has examined factors related to gang membership and offending, research on the relationship between gangs and victimization is limited. The present study builds on previous research and examines gang membership, victimization, and self-control among 2,414 jail inmates. Results from self-report surveys indicate that gang…

  14. U.S. Juvenile Arrests: Gang Membership, Social Class, and Labeling Effects

    Science.gov (United States)

    Tapia, Mike

    2011-01-01

    This study addresses the link between gang membership and arrest frequency, exploring the Gang x Socioeconomic status interaction on those arrests. Notoriously poor, delinquent, and often well-known to police, America's gang youth should have very high odds of arrest. Yet it is unclear whether mere membership in a gang increases the risk of arrest…

  15. Self-Definitions of Gang Membership and Involvement in Delinquent Activities.

    Science.gov (United States)

    Bjerregaard, Beth

    2002-01-01

    Examined the relationship between various methods of operationalizing gang membership and delinquency. Surveys of inner city adolescents indicated that teens reporting membership in organized gangs were far more likely to believe their gangs possessed characteristics typically associated with traditional street gangs. Teens who considered…

  16. 25 CFR 39.210 - When must a school drop a student from its membership?

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false When must a school drop a student from its membership? 39.210 Section 39.210 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR EDUCATION THE INDIAN... must a school drop a student from its membership? If a student is absent for 10 consecutive school...

  17. 10 CFR 1800.12 - Procedures for declaring a state eligible for membership in the Compact.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Procedures for declaring a state eligible for membership in the Compact. 1800.12 Section 1800.12 Energy NORTHEAST INTERSTATE LOW-LEVEL RADIOACTIVE WASTE... COMPACT § 1800.12 Procedures for declaring a state eligible for membership in the Compact. (a) Any...

  18. 76 FR 27311 - Cobb Customer Requesters v. Cobb Electric Membership Corporation, Cobb Energy Management...

    Science.gov (United States)

    2011-05-11

    ... III; Notice of Complaint Take notice that on April 26, 2011, Cobb Customer Requesters (CCR or Complainant) filed a complaint against Cobb Electric Membership Corporation (Cobb EMC), Cobb Energy Management... Energy Regulatory Commission Cobb Customer Requesters v. Cobb Electric Membership Corporation,...

  19. 10th January 2012 - President of the Republic of Serbia B. Tadic on the occasion of the signature of the Agreement concerning the granting of the status of associate membership as the pre-stage to membership at CERN.

    CERN Multimedia

    Maximilien Brice

    2012-01-01

    10th January 2012 - President of the Republic of Serbia B. Tadic on the occasion of the signature of the Agreement concerning the granting of the status of associate membership as the pre-stage to membership at CERN.

  20. Theoretical prediction of the damping of a railway wheel with sandwich-type dampers

    Science.gov (United States)

    Merideno, Inaki; Nieto, Javier; Gil-Negrete, Nere; Giménez Ortiz, José Germán; Landaberea, Aitor; Iartza, Jon

    2014-09-01

    This paper presents a procedure for predicting the damping added to a railway wheel when sandwich-type dampers are installed. Although there are different ways to reduce the noise generated by a railway wheel, most devices are based on the mechanism of increasing wheel damping. This is why modal damping ratios are a clear indicator of the efficiency of the damping device and essential when a vibro-acoustic study of a railway wheel is carried out. Based on a number of output variables extracted from the wheel and damper models, the strategy explained herein provides the final damping ratios of the damped wheel. Several different configurations are designed and experimentally tested. Theoretical and experimental results agree adequately, and it is demonstrated that this procedure is a good tool for qualitative comparison between different solutions in the design stages.

  1. Fractal Patterns of Fracture in Sandwich Composite Materials under Biaxial Tension

    Institute of Scientific and Technical Information of China (English)

    JingFANG; XuefengYAO; 等

    1996-01-01

    The paper presents a successful experiment to generate a fractal pattern of branching cracks in a brittle material sandwiched in ductile pates.A glass sheet bonded between two polycarbonate plates was heated at different levels of temperatures and the stress field due to the difference of thermal coefficients of the materials was solved by combining the results from isochromatic fringes and thermal stress analysis.At a critical degree of temperature,a crack was initiated at a point and soon produced crack branches to release the stored energy.A tree-like fractal patterns of the branch cracks was then developed with the growth of the branches that subsequently produced more branches on their ways of propagation.The fractakl dimension of the fracture pattern was evaluated and the mechanism of the fragmentation was analyzed with the help of the residual stress field of isochromatic and isoclinic patterns.

  2. Modelling the behaviour of composite sandwich structures when subject to air-blast loading

    Directory of Open Access Journals (Sweden)

    H Arora

    2016-09-01

    Full Text Available Large-scale glass fibre reinforced polymer (GFRP and carbon fibre reinforced polymer (CFRP sandwich structures (1.6 m x 1.3 m were subject to explosive air blast (100 kg TNT equivalent at stand-off distances of 14 m. Digital image correlation (DIC was used to obtain full-field data for the rear-face of each deforming target. A steel plate of comparable mass per unit area was also subjected to the same blast conditions for comparison. The experimental data was then verified with finite element models generated in Abaqus/Explicit. Close agreement was obtained between the numerical and experimental results, confirming that the CFRP panels had a superior blast performance to the GFRP panels. Moreover all composite targets sustained localised failures (that were more severe in the GFRP targets but retained their original shape post blast. The rear-skins remained intact for each composite target with core shear failure present.

  3. Reducing Prejudice With Labels: Shared Group Memberships Attenuate Implicit Bias and Expand Implicit Group Boundaries.

    Science.gov (United States)

    Scroggins, W Anthony; Mackie, Diane M; Allen, Thomas J; Sherman, Jeffrey W

    2016-02-01

    In three experiments, we used a novel Implicit Association Test procedure to investigate the impact of group memberships on implicit bias and implicit group boundaries. Results from Experiment 1 indicated that categorizing targets using a shared category reduced implicit bias by increasing the extent to which positivity was associated with Blacks. Results from Experiment 2 revealed that shared group membership, but not mere positivity of a group membership, was necessary to reduce implicit bias. Quadruple process model analyses indicated that changes in implicit bias caused by shared group membership are due to changes in the way that targets are evaluated, not to changes in the regulation of evaluative bias. Results from Experiment 3 showed that categorizing Black targets into shared group memberships expanded implicit group boundaries.

  4. The role of delinquency, proactive aggression, psychopathy and behavioral school engagement in reported youth gang membership.

    Science.gov (United States)

    Ang, Rebecca P; Huan, Vivien S; Chan, Wei Teng; Cheong, Siew Ann; Leaw, Jia Ning

    2015-06-01

    Given the robust positive association between gangs and crime, a better understanding of factors related to reported youth gang membership is critical and especially since youth in gangs are a universal concern. The present study investigated the role of delinquency, proactive aggression, psychopathy and behavioral school engagement in reported youth gang membership using a large sample of 1027 Singapore adolescents. Results from logistic regression showed that delinquency, proactive aggression, and behavioral school engagement were statistically significant risk factors for reported youth gang membership, and that psychopathy was not related to reported gang membership. Implications for prevention and intervention work with respect to youth gang membership were discussed. In particular, strengthening students' engagement with school and meaningful school-related activities and developing supportive teacher-student relationships are particularly important in working with young people with respect to prevention work. Additionally, the present study's theoretical and empirical contributions were also discussed.

  5. Galactic membership of BL Her type variable stars

    Science.gov (United States)

    Jurkovic, M. I.; Stojanovic, M.; Ninkovic, S.

    2016-05-01

    As the RR Lyrae stars evolve on the Hertzsprung-Russell diagram they are believed to become short period Type II Cepheids, known as BL Her type (with a pulsation period from 1 to 3-8 days). Assuming that their mass is around 0.5-0.6M_Sol, and that they are low metallicity objects, they were thought to belong to the halo of the Milky Way. We investigated seven Galactic short period Type II Cepheids (BL Her, SW Tau, V553 Cen, DQ And, BD Cas, V383 Cyg, and KT Com) in order to establish their membership within the Galactic structure using the kinematic approach. Gaia should provide us with more data needed to conduct the study of the whole sample.

  6. Galactic membership of BL Her type variable stars

    CERN Document Server

    Jurkovic, Monika I; Ninković, Slobodan

    2016-01-01

    As the RR Lyrae stars evolve on the Hertzsprung-Russell diagram they are believed to become short period Type II Cepheids, known as BL Her type (with a pulsation period from $1$ to $3-8$ days). Assuming that their mass is around $0.5 - 0.6 {\\rm M}_{\\odot}$, and that they are low metallicity objects, they were thought to belong to the halo of the Milky Way. We investigated seven Galactic short period Type II Cepheids (BL Her, SW Tau, V553 Cen, DQ And, BD Cas, V383 Cyg, and KT Com) in order to establish their membership within the Galactic structure using the kinematic approach. $Gaia$ should provide us with more data needed to conduct the study of the whole sample.

  7. The influence of group membership on young children's prosocial behaviour.

    Science.gov (United States)

    Over, Harriet

    2017-08-08

    Young children can be extremely prosocial-willing to help and share with others and comfort them in distress. However, the origins of social problems like prejudice and discrimination also appear early in development. In this paper, I discuss research investigating how group membership affects children's tendency to be prosocial. Existing research on this topic has focused primarily on sharing behaviour and shown that, in general, children allocate more resources to members of their own groups. After reviewing this important literature, I make the case for extending research with young children to other forms of prosociality. This has the potential to inform our understanding of the mechanisms behind ingroup favouritism in prosociality and help us understand routes towards interventions to encourage more egalitarian behaviour. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Fuzzy adaptive learning control network with sigmoid membership function

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    To get simpler operation in modified fuzzy adaptive learning control network (FALCON) in some engineering application, sigmoid nonlinear function is employed as a substitute of traditional Gaussian membership function. For making the modified FALCON learning more efficient and stable, a simulated annealing (SA) learning coefficient is introduced into learning algorithm. At first, the basic concepts and main advantages of FALCON were briefly reviewed. Subsequently, the topological structure and nodes operation were illustrated; the gradient-descent learning algorithm with SA learning coefficient was derived;and the distinctions between the archetype and the modification were analyzed. Eventually, the significance and worthiness of the modified FALCON were validated by its application to probability prediction of anode effect in aluminium electrolysis cells.

  9. Definition of Household Membership in International Migration Surveys

    Directory of Open Access Journals (Sweden)

    Turgay Ünalan

    2005-01-01

    Full Text Available Using data from national surveys conducted within the scope of the Eurostat project titled “Push and Pull Factors of International Migration”, analyses are presented using different definitions (narrow versus wide of household membership in migrant-sending countries (Egypt, Ghana, Morocco, Senegal and Turkey to see if different definitions are helpful in identifying and increasing the number of migrants who are or was a part of those households. When broad definition was used, the increase in the international migrant members was especially considerable in recent and current migrant households. The findings demonstrated that it was possible to trace an important number of international migrants back in their country of origin and to collect data using proxy interviews. However, it was still impossible to survey emigrants who left the country as a household, those who were not expected to return to the household, those belonging to some dissolved households, or those who died.

  10. An h-p Finite Element Vibration Analysis of Open Conical Sandwich Panels and Conical Sandwich Frusta

    Science.gov (United States)

    BARDELL, N. S.; LANGLEY, R. S.; DUNSDON, J. M.; AGLIETTI, G. S.

    1999-09-01

    The vibration study of a general three-layer conical sandwich panel based on theh -p version of the finite element method is presented in this paper. No restriction is placed on the degree of curvature of the shell, thereby relaxing the strictures associated with shallow shell theory. The methodology incorporates a new set of trigonometric functions to provide the element p -enrichment, and elements may be joined together to model either open conical panels, or complete conical frusta (circumferentially connected, but open at each end). The full range of classical boundary conditions, which includes free, clamped, simply supported and shear diaphragm edges, may be applied in any combination to open and closed panels, thereby facilitating the study of a wide range of conical sandwich shells. The convergence properties of this element have been established for different combinations of the h - and p -parameters, thereby assuring its integrity for more general use. Since very little work has been reported on the vibration characteristic of either circumferentially closed or open conical sandwich panels, the main thrust of this work has been to present and validate an efficient modelling technique, rather than to perform numerous parameter and/or sensitivity studies. To this end, some new results are presented and subsequently validated using a commercially available finite element package. It is shown that for results of comparable accuracy, models constructed using the h-p formulation require significantly fewer degrees of freedom than those assembled using the commercial package. Some preliminary experimental results are also included for completeness.

  11. Prediction of class membership of biodiesels using chemometrics.

    Science.gov (United States)

    Mustafa, Zylia; Milina, Rumyana; Simeonova, Pavlina A; Tsakovski, Stefan L; Simeonov, Vasil D

    2015-01-01

    Recently, serious scientific and technological attention is paid to creation of alternative energy sources, including biofuels. The assessment of the quality of the biofuels produced and of the raw materials needed for the production technology is an important scientific challenge. One of the major sources for biodiesel production is plant oils material (sunflower, rapeseed, palm, soya etc.). Since plants are complex system from the biota it is not easy to find specific chemical components responsible for their ability to serve as biodiesels. The characterization and classification of plant sources as biofuel material could be reliably estimated only by the use of multivariate statistical approaches (chemometrics). The chemometric expertise makes it possible not only to classify different biofuel sources into similarity classes but also to predict the membership of unknown by origin chemically analyzed samples to already existing classes. The present study deals with the prediction of the class membership of several unknown by origin samples, which are included in a large data set with FAME profiles of biodiesel plant sources. Using a data set from chromatographic analysis of fatty acid methyl esters profiles (FAME) of different plant biodiesel sources and applying the chemometric technique know as partial least squares-discriminant analysis (PLS - DA) a pattern recognition procedure is developed to: I. Model classes of similarity of biodiesel plant sources using their FAME profiles not taking into account the samples with unknown origin; II. Classify correctly the samples with unknown origin to the previously defined classes of biodiesel sources (palm oil, soybean oil, peanut oil, rapeseed oil, sunflower oil and maize oil). The prediction is successfully achieved for all samples with previously unknown origin. This pattern recognition approach is applied for the first time in the field of biodiesel classification and modeling tasks.

  12. Multiple-turnover cleavage of double-stranded DNA by sandwiched zinc-finger nuclease.

    Science.gov (United States)

    Mineta, Yusuke; Okamoto, Tomoyuki; Takenaka, Kosuke; Doi, Norio; Aoyama, Yasuhiro; Sera, Takashi

    2009-01-01

    To refine zinc-finger nuclease (ZFN) technology, we constructed a sandwiched ZFN, in which a DNA cleavage enzyme was sandwiched with two artificial zinc-finger proteins (AZPs). Because the sandwiched ZFN is designed to cleave the DNA between the two AZP-binding sites, the sandwiched ZFN is expected to bind preferentially to a DNA substrate rather than to cleavage products and thereby cleave it with multiple turnovers. To prove the concept, we sandwiched a staphylococcal nuclease (SNase), which cleaves DNA as a monomer, between two 3-finger AZPs. The AZP-sandwiched SNase cleaved large amounts of dsDNA site-specifically. Such multiple-turnover cleavage was not observed with control nucleases that possess a single AZP.

  13. Fatigue fracture of fiber reinforced polymer honeycomb composite sandwich structures for gas turbine engines

    Science.gov (United States)

    Nikhamkin, Mikhail; Sazhenkov, Nikolai; Samodurov, Danil

    2017-05-01

    Fiber reinforced polymer honeycomb composite sandwich structures are commonly used in different industries. In particular, they are used in the manufacture of gas turbine engines. However, fiber reinforced polymer honeycomb composite sandwich structures often have a manufacturing flaw. In theory, such flaws due to their rapid propagation reduce the durability of fiber reinforced polymer honeycomb composite sandwich structures. In this paper, bending fatigue tests of fiber reinforced polymer honeycomb composite sandwich structures with manufacturing flaws were conducted. Comparative analysis of fatigue fracture of fiber reinforced polymer honeycomb composite sandwich specimens was conducted before and after their bending fatigue tests. The analysis was based on the internal damage X-ray observation of fiber reinforced polymer honeycomb composite sandwich specimens.

  14. Experimental investigation on vibration characteristics of sandwich beams with magnetorheological elastomers cores

    Institute of Scientific and Technical Information of China (English)

    魏克湘; 孟光; 张文明; 朱石沙

    2008-01-01

    A sandwich beam specimen was fabricated by treating with MR elastomers between two thin aluminum face-plates.Experiment was carried out to investigate the vibration responses of the sandwich beam with respect to the intensity of the magnetic field and excitation frequencies.The results show that the sandwich beams with MR elastomers cores have the capabilities of shifting natural frequencies and the vibration amplitudes decrease with the variation of the intensity of external magnetic field.

  15. Effects of Subzero Temperatures and Sea Water Immersion on Damage Initiation and Growth in Sandwich Composites

    Science.gov (United States)

    2008-12-10

    single cantilever beam sandwich test. The TSD is perhaps 19 An improved methodology for measuring the interracial toughness of sandwich beams 3...measuring the interracial toughness of sandwich beams 5 Table 4.1. Material properties Glass face Glass face Carbon „ , ,, Loading L...which shows the relationship between reaction forces for an MSCB specimen with 12 ply glass face sheets at different crack lengths. It is observed

  16. 1. Mono([8]annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

    Energy Technology Data Exchange (ETDEWEB)

    Boussie, T.R.

    1991-10-01

    A reproducible, high-yield synthesis of mono([8]annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono([8]annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.

  17. 1. Mono((8)annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

    Energy Technology Data Exchange (ETDEWEB)

    Boussie, T.R.

    1991-10-01

    A reproducible, high-yield synthesis of mono((8)annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono((8)annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.

  18. Fabrication and Testing of Carbon Fiber Reinforced Truss Core Sandwich Panels

    Institute of Scientific and Technical Information of China (English)

    Bing Wang; Linzhi Wu; Li Ma; Qiang Wang; Shanyi Du

    2009-01-01

    Truss core sandwich panels reinforced by carbon fibers were assembled with bonded laminate facesheets and carbon fiber reinforced truss cores. The top and bottom facesheets were interconnected with truss cores. Both ends of the truss cores were embedded into four layers of top and bottom facesheets. The mechanical properties of truss core sandwich panels were then investigated under out-of-plane and in-plane compression loadings to reveal the failure mechanisms of sandwich panels. Experimental results indicated that the mechanical behavior of sandwich structure under in-plane loading is dominated by the buckling and debonding of facesheets.

  19. Fiber-Reinforced-Foam (FRF) Core Composite Sandwich Panel Concept for Advanced Composites Technologi

    Science.gov (United States)

    2010-01-01

    Fiber-Reinforced-Foam (FRF) Core Composite Sandwich Panel Concept for Advanced Composites Technologies Project - Preliminary Manufacturing Demonstration Articles for Ares V Payload Shroud Barrel Acreage Structure

  20. Giant magnetoresistance effect in Ni buffered Co/Cu/Co sandwich

    Institute of Scientific and Technical Information of China (English)

    LI; Tie(李铁)

    2002-01-01

    The effects of Ni buffer layer on the giant magnetoresistance structure of Co/Cu/Co sandwich are investigated systematically in this paper.It is found that Ni buffer layer can induce the crystallization of the lower Ni/Co layer and produce small coercivity,thus enlarging the difference in the magnetic behavior between the two magnetic layers in the sandwich.Moreover,the use of the Ni buffer layer can also improve the interface flatness in the sandwich.All these factors enhance the sensitivity of the Ni buffered sandwich.``

  1. Combined-load buckling behavior of metal-matrix composite sandwich panels under different thermal environments

    Science.gov (United States)

    Ko, William L.; Jackson, Raymond H.

    1991-01-01

    Combined compressive and shear buckling analysis was conducted on flat rectangular sandwich panels with the consideration of transverse shear effects of the core. The sandwich panel is fabricated with titanium honeycomb core and laminated metal matrix composite face sheets. The results show that the square panel has the highest combined load buckling strength, and that the buckling strength decreases sharply with the increases of both temperature and panel aspect ratio. The effect of layup (fiber orientation) on the buckling strength of the panels was studied in detail. The metal matrix composite sandwich panel was much more efficient than the sandwich panel with nonreinforced face sheets and had the same specific weight.

  2. Mechanical evaluation with fe analysis of sandwich panels for wind turbine blade

    Energy Technology Data Exchange (ETDEWEB)

    Yasaswi, M.; Naveen, P.N.E.; Prasad, R.V. [GIET. Dept. of Mechanical Engineering, Rajahmundry (India)

    2012-07-01

    Sandwich panels are notable for their structural efficiency and are used as load bearing components in various branches of engineering, especially in aerospace and marine industries. The objective of the present work is to perform computer-aided analysis on sandwich panels. The analysis of sandwich panel with truss core are compared with other four types of sandwich panel with continuous corrugated core, top hat core, zed core and channel core. The basic reason to use sandwich structure is to save weight, however smooth skins and excellent fatigue resistance are also attributes of a sandwich structure. A sandwich is comprised of two layered composite materials formed by bonding two or more thin facings or face sheets to relatively thick core materials. In this type of construction the facings resist nearly all of the in-plane loads and out-of-plane bending moments. The thin facings provide nearly all of the bending stiffness because they are generally of a much higher modulus material is located at a greatest distance from the neutral axis of the component. The basic concept of sandwich panel is that the facings carry the bending loads and the core carries the shear loads. The main function of the core material is to distribute local loads and stresses over large areas. From all this analysis it is concluded that the truss core Sandwich panels can be used in wind turbine blade design. (Author)

  3. Current rectification in nickelocenylferrocene sandwiched between two gold electrodes.

    Science.gov (United States)

    Matsuura, Yukihito

    2013-01-07

    I present a theoretical study of the electronic transport properties of nickelocenylferrocene sandwiched between gold electrodes. Compared with the biferrocene system, the nickelocenylferrocene system had high electrical conduction and rectification in the bias range -1 to 1 V. Furthermore, the spin-down states of the nickelocenylferrocene system exhibited perfect spin-filtering properties. From the electronic states of the nickelocenylferrocene, it was found that the rectification was caused by a difference in the bias-dependent behaviors between the Fe 3d and Ni 3d orbitals.

  4. A Conformal Thin-Sandwich Solver for Generic Initial Data

    CERN Document Server

    East, William E; Pretorius, Frans

    2012-01-01

    We present a new scheme for constructing initial data for the Einstein field equations using the conformal thin-sandwich formulation that does not assume conformal flatness or approximate Killing vectors. This includes a method for determining free data based on superposition, as well as a way to handle black hole singularities without excision. We numerically solve the constraint equations using a multigrid algorithm with mesh refinement. We demonstrate the efficacy of the method with initial data solutions for several applications: a quasi-circular binary black hole merger, a dynamical capture black hole-neutron star merger, and an ultrarelativistic collision.

  5. Standard Test Method for Dimensional Stability of Sandwich Core Materials

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2002-01-01

    1.1 This test method covers the determination of the sandwich core dimensional stability in the two plan dimensions. 1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given may be approximate. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  6. Standard Test Method for Shear Fatigue of Sandwich Core Materials

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This test method covers determination of the effect of repeated shear loads on sandwich core materials. 1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given may be approximate. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  7. Hydrogen storage property of sandwiched magnesium hydride nanoparticle thin film

    Energy Technology Data Exchange (ETDEWEB)

    Barcelo, Steven; Rogers, Matthew; Grigoropoulos, Costas P.; Mao, Samuel S. [Lawrence Berkeley National Laboratory and Department of Mechanical Engineering, University of California at Berkeley, Berkeley, CA 94720 (United States)

    2010-07-15

    Hydrogen sorption property of magnesium (Mg) in the form of sandwiched Pd/Mg/Pd films is investigated. Pulsed laser deposition method was applied to deposit the samples consisting of films of nanoparticles. The enthalpy of formation of MgH{sub 2} was found to be -68 kJ/mol H{sub 2} for films with nanoparticle size on the order of 50 nm, which is smaller than the value for bulk MgH{sub 2} and may be explained by the concept of excess volume. (author)

  8. Optimization of the curing process of a sandwich panel

    Science.gov (United States)

    Phyo Maung, Pyi; Tatarnikov, O.; Malysheva, G.

    2016-10-01

    This study presented finite element modelling and experimental measurements of temperatures during the autoclave curing of the T-50 aircraft wing sandwich panel. This panel consists of upper and lower carbon fibre based laminates and an aluminium foil honeycomb. The finite element modelling was performed using the Femap-Nastran product. During processing, the temperature at various points on the surface of the panel was measured using the thermocouples. The finite element method simulated the thermal conditions and determined the temperatures in the different parts of the panel for a full cycle of the curing process. A comparison of the calculated and experimental data shows that their difference does not exceed 6%.

  9. Experimental Investigations of Compressed Sandwich Composite/Honeycomb Cylindrical Shells

    Science.gov (United States)

    Muc, A.; Stawiarski, A.; Romanowicz, P.

    2017-06-01

    This article explains in some details the behaviour of thick, deep cylindrical sandwich panels subjected to compressive loads. In general, experimental results indicated that two different forms of failure have been observed - the first corresponds to the overall buckling and the second to the facesheet wrinkling. The obtained experimentally damages of shells are verified and validated with the use of the FE analysis, 2-D and 3-D both in the linear and non-linear approach. The unidirectional strain gauges were applied to detect the initiation of the overall buckling mode.

  10. FINITE ELEMENT MODELING OF THIN CIRCULAR SANDWICH PLATES DEFLECTION

    Directory of Open Access Journals (Sweden)

    K. S. Kurachka

    2014-01-01

    Full Text Available A mathematical model of a thin circular sandwich plate being under the vertical load is proposed. The model employs the finite element method and takes advantage of an axisymmetric finite element that leads to the small dimension of the resulting stiffness matrix and sufficient accuracy for practical calculations. The analytical expressions for computing local stiffness matrices are found, which can significantly speed up the process of forming the global stiffness matrix and increase the accuracy of calculations. A software is under development and verification. The discrepancy between the results of the mathematical model and those of analytical formulas for homogeneous thin circularsandwich plates does not exceed 7%.

  11. Sandwich Hologram Interferometry For Determination Of Sacroiliac Joint Movements

    Science.gov (United States)

    Vukicevic, S.; Vinter, I.; Vukicevic, D.

    1983-12-01

    Investigations were carried out on embalmed and fresh specimens of human pelvisis with preserved lumbar spines, hip joints and all the ligaments. Specimens were tested under static vertical loading by pulsed laser interferometry. The deformations and behaviour of particular pelvic parts were interpreted by providing computer interferogram models. Results indicate rotation and tilting of the sacrum in the dorso-ventral direction and small but significant movements in the cranio-caudal direction. Sandwich holography proved to be the only applicable method when there is a combination of translation and tilt in the range of 200 μm to 1.5 mm.

  12. Optical and thermophysical parameters measurement using sandwich photodetectors

    Science.gov (United States)

    Turinov, Valery I.

    1993-12-01

    A method is reported for estimating thermophysical and optical parameters, in which a two- spectral band sandwich photodetector is used. The sensitivity ranges of such a sensor are 2 - 5 micrometers and 8 - 14 micrometers . On irradiating an object's surface by a short radiation pulse the photodetector collected signals U1, U2 and the rates of their changes (dU1/dt), (dU2/dt) are recorded. These pertain to the same area on the object's surface and belong to the two spectral ranges mentioned. The parameters of the object are evaluated by means of calculations with the values measured.

  13. Done in 60 minutes building a custom DotNetNuke membership provider

    CERN Document Server

    Chagoury, Antonio

    2010-01-01

    This Wrox Blox will give you a high-level overview of the core Membership Provider and its default implementation, (ASP.NET Membership), and demonstrate how to build and configure your own custom provider. The Provider Model is a design pattern introduced in .NET to provide a simple way to extend API functionality. DotNetNuke uses this architecture to allow some of its core functionality to be replaced without modifying core code.  While this Wrox Blox describes how to develop a custom DotNetNuke Membership Provider, it also provides some general information about the .NET Framework's (2.0 a

  14. Fuzzy Multi-Objective Transportation Planning with Modified S-Curve Membership Function

    Science.gov (United States)

    Peidro, D.; Vasant, P.

    2009-08-01

    In this paper, the S-Curve membership function methodology is used in a transportation planning decision (TPD) problem. An interactive method for solving multi-objective TPD problems with fuzzy goals, available supply and forecast demand is developed. The proposed method attempts simultaneously to minimize the total production and transportation costs and the total delivery time with reference to budget constraints and available supply, machine capacities at each source, as well as forecast demand and warehouse space constraints at each destination. We compare in an industrial case the performance of S-curve membership functions, representing uncertainty goals and constraints in TPD problems, with linear membership functions.

  15. Effects Of Membership Of Cooperative Organisations And Determinants On Farmer-Members Income In Rural Anambra State Nigeria

    Directory of Open Access Journals (Sweden)

    Nkechi Cordelia Ojiagu

    2015-08-01

    Full Text Available ABSTRACT The study examined the effect of membership of cooperative societies on the economic activities of farmers as well as the determinants of their income in rural Nigeria focusing on Anambra State. Data from 2506 members selected through multi-stage stratified random sampling were analyzed. The study found among others that members incomes are dependent upon their socio-economic profile such as age marital status and membership or otherwise of cooperative societies education cooperative marketing credit gender and business expertise. Also respondents depend largely on farming related activities for generation of income in the study area. Furthermore it was found that the major challenge of the farmer-members is inadequate fund poor education and illiteracy among most members conflict among members and lack of access to farm input. The Nigerian government is advised to formulate policies that will incorporate information from the local level that can support planning implementation and evaluation of programmes that can enhance farmers income this however will influence the pattern of agricultural growth in ways that can change income level of rural farmers to grow fast. The study recommends that cooperatives should intensify their education of members to gain more benefits and that government non-governmental organizations and international development agencies should show interest in supervising and providing development support to Farmers Cooperative Societies in rural Nigeria.

  16. When Is Group Membership Zero-Sum? Effects of Ethnicity, Threat, and Social Identity on Dual National Identity.

    Directory of Open Access Journals (Sweden)

    Michael Smithson

    Full Text Available This paper presents an investigation into marginalizing racism, a form of prejudice whereby ingroup members claim that specific individuals belong to their group, but also exclude them by not granting them all of the privileges of a full ingroup member. One manifestation of this is that perceived degree of outgroup membership will covary negatively with degree of ingroup membership. That is, group membership may be treated as a zero-sum quantity (e.g., one cannot be both Australian and Iraqi. Study 1 demonstrated that judges allocate more zero-sum membership assignments and lower combined membership in their country of origin and their adopted country to high-threat migrants than low-threat migrants. Study 2 identified a subtle type of zero-sum reasoning which holds that stronger degree of membership in one's original nationality constrains membership in a new nationality to a greater extent than stronger membership in the new nationality constrains membership in one's original nationality. This pattern is quite general, being replicated in large samples from four nations (USA, UK, India, and China. Taken together, these studies suggest that marginalizing racism is more than a belief that people retain a "stain" from membership in their original group. Marginalizing racism also manifests itself as conditional zero-sum beliefs about multiple group memberships.

  17. When Is Group Membership Zero-Sum? Effects of Ethnicity, Threat, and Social Identity on Dual National Identity.

    Science.gov (United States)

    Smithson, Michael; Sopeña, Arthur; Platow, Michael J

    2015-01-01

    This paper presents an investigation into marginalizing racism, a form of prejudice whereby ingroup members claim that specific individuals belong to their group, but also exclude them by not granting them all of the privileges of a full ingroup member. One manifestation of this is that perceived degree of outgroup membership will covary negatively with degree of ingroup membership. That is, group membership may be treated as a zero-sum quantity (e.g., one cannot be both Australian and Iraqi). Study 1 demonstrated that judges allocate more zero-sum membership assignments and lower combined membership in their country of origin and their adopted country to high-threat migrants than low-threat migrants. Study 2 identified a subtle type of zero-sum reasoning which holds that stronger degree of membership in one's original nationality constrains membership in a new nationality to a greater extent than stronger membership in the new nationality constrains membership in one's original nationality. This pattern is quite general, being replicated in large samples from four nations (USA, UK, India, and China). Taken together, these studies suggest that marginalizing racism is more than a belief that people retain a "stain" from membership in their original group. Marginalizing racism also manifests itself as conditional zero-sum beliefs about multiple group memberships.

  18. An Initial Membership Profile of the Financial Therapy Association

    Directory of Open Access Journals (Sweden)

    Brett Coffman

    2012-01-01

    Full Text Available The Financial Therapy Association (FTA was established in 2010 to bring practitioners and researchers together to develop tools and techniques to address emotional, behavioral, relational, cognitive, and economic aspects of financial health. Ultimately, those interested in the new field of financial therapy are most interested in answering the following key questions: Why do people do what they do with money and how can practitioners better help their clients deal with the complexities of the volatile economy that places tremendous stress on individuals and families? Financial therapy is emerging as a unique field that links scholars, practitioners, and mental health professionals in ways that consider these and other important questions. FTA is especially unique because of its diverse and accomplished membership, which includes mental health and financial professionals, educators, and researchers. The purpose of this “Profile” is to highlight how experienced and established professionals from both the mental health and finance domains have joined together to build a new profession, and to provide benchmark information regarding how the practice of financial therapy is occurring in the United States and other countries.

  19. Mentality or morality? Membership categorization, multiple meanings and mass murder.

    Science.gov (United States)

    Rapley, Mark; McCarthy, David; McHoul, Alec

    2003-09-01

    A central topic for social psychology is how we identify, categorize or represent ourselves to ourselves and to each other. Previous work on this topic stemming from attribution theory, social identity theory, self-categorization theory and social representations theory has tended to accept the dominant cognitivist tenet of an interior self which is (with varying degrees of success) re-presented in ordinary discourse. Against this tradition, and drawing on membership categorization analysis, we argue here for an attention to ordinary members' methods of categorizing the self. Such devices are constitutive of a culture. Accounts of the self (whether lay or professional) cannot avoid reliance on such devices. Our particular case involves a corpus of materials from the press surrounding the Port Arthur massacre: the shooting of 35 people by a lone gunman, Martin Bryant, in Tasmania in 1996. In this case, where public accountings for what 'makes up' a particular person are tied to an otherwise inexplicable but ultra-newsworthy event, we find that lay and professional methods of accounting are remarkably congruent. One of the reasons for this congruence, we suggest, is that the categorization of persons is a fundamentally moral matter. Devices for producing everyday moral accounts, in actual practical circumstances, precede and ground, for example, 'technical', 'clinical' or 'scientific' judgments. We conclude that describing such routine (but ultimately grounding) cultural devices can be a central goal of social psychology, as opposed to explaining 'the self' by tacitly relying upon those same devices in an unacknowledged and unproblematized fashion.

  20. Sandwiched confinement of quantum dots in graphene matrix for efficient electron transfer and photocurrent production.

    Science.gov (United States)

    Zhu, Nan; Zheng, Kaibo; Karki, Khadga J; Abdellah, Mohamed; Zhu, Qiushi; Carlson, Stefan; Haase, Dörthe; Žídek, Karel; Ulstrup, Jens; Canton, Sophie E; Pullerits, Tõnu; Chi, Qijin

    2015-05-21

    Quantum dots (QDs) and graphene are both promising materials for the development of new-generation optoelectronic devices. Towards this end, synergic assembly of these two building blocks is a key step but remains a challenge. Here, we show a one-step strategy for organizing QDs in a graphene matrix via interfacial self-assembly, leading to the formation of sandwiched hybrid QD-graphene nanofilms. We have explored structural features, electron transfer kinetics and photocurrent generation capacity of such hybrid nanofilms using a wide variety of advanced techniques. Graphene nanosheets interlink QDs and significantly improve electronic coupling, resulting in fast electron transfer from photoexcited QDs to graphene with a rate constant of 1.3 × 10(9) s(-1). Efficient electron transfer dramatically enhances photocurrent generation in a liquid-junction QD-sensitized solar cell where the hybrid nanofilm acts as a photoanode. We thereby demonstrate a cost-effective method to construct large-area QD-graphene hybrid nanofilms with straightforward scale-up potential for optoelectronic applications.

  1. Sandwiched confinement of quantum dots in graphene matrix for efficient electron transfer and photocurrent production

    Science.gov (United States)

    Zhu, Nan; Zheng, Kaibo; Karki, Khadga J.; Abdellah, Mohamed; Zhu, Qiushi; Carlson, Stefan; Haase, Dörthe; Žídek, Karel; Ulstrup, Jens; Canton, Sophie E.; Pullerits, Tõnu; Chi, Qijin

    2015-05-01

    Quantum dots (QDs) and graphene are both promising materials for the development of new-generation optoelectronic devices. Towards this end, synergic assembly of these two building blocks is a key step but remains a challenge. Here, we show a one-step strategy for organizing QDs in a graphene matrix via interfacial self-assembly, leading to the formation of sandwiched hybrid QD-graphene nanofilms. We have explored structural features, electron transfer kinetics and photocurrent generation capacity of such hybrid nanofilms using a wide variety of advanced techniques. Graphene nanosheets interlink QDs and significantly improve electronic coupling, resulting in fast electron transfer from photoexcited QDs to graphene with a rate constant of 1.3 × 109 s-1. Efficient electron transfer dramatically enhances photocurrent generation in a liquid-junction QD-sensitized solar cell where the hybrid nanofilm acts as a photoanode. We thereby demonstrate a cost-effective method to construct large-area QD-graphene hybrid nanofilms with straightforward scale-up potential for optoelectronic applications.

  2. Active structural health monitoring of composite plates and sandwiches

    Directory of Open Access Journals (Sweden)

    Sadílek P.

    2013-12-01

    Full Text Available The aim of presented work is to design, assemble and test a functional system, that is able to reveal damage from impact loading. This is done by monitoring of change of spectral characteristics on a damaged structure that is caused by change of mechanical properties of material or by change of structure’s geometry. Excitation and monitoring of structures was done using piezoelectric patches. Unidirectional composite plate was tested for eigenfrequencies using chirp signal. The eigenfrequencies were compared to results from experiments with an impact hammer and consequently with results from finite element method. Same method of finding eigenfrequencies was used on a different unidirectional composite specimen. Series of impacts were performed. Spectrum of eigenfrequencies was measured on undamaged plate and then after each impact. Measurements of the plate with different level of damage were compared. Following experiments were performed on sandwich materials where more different failures may happen. Set of sandwich beams (cut out from one plate made of two outer composite layers and a foam core was investigated and subjected to several impacts. Several samples were impacted in the same manner to get comparable results. The impacts were performed with growing impact energy.

  3. A Z_m Ham Sandwich Theorem for Complex Measures

    CERN Document Server

    Simon, Steven

    2010-01-01

    A "ham sandwich" theorem is derived for n complex measures on C^n. For each integer m >= 2, a complex hyperplane H and m corresponding "1/m" sectors are found, satisfying the condition that the "rotational average" of the measures of these sectors is zero. The result can be seen as a kind of rotational equipartition of each measure by a regular "m-fan". The proof of the theorem is topological, based on a Z_m version of the Borsuk-Ulam theorem for punctured (2n - 1)-spheres in C^n. Any finite real measure on R^{2n} can be seen as a type of complex measure on C^n, so the theorem can be applied to n finite measures on R^{2n}. In the case that m = 3, this shows the existence of a regular 3-fan which trisects each of the n measures. Similarly, any pair of finite real measures on R^{2n} can be naturally identified with a complex measure on C^n, so the theorem applies to 2n finite measures on R^{2n}. This yields a rotational condition on pairs of finite measures, and the original ham sandwich theorem for R^{2n} is r...

  4. Dispersion of guided waves in composite laminates and sandwich panels

    Science.gov (United States)

    Schaal, Christoph; Mal, Ajit

    2015-03-01

    In composite structures, damages are often invisible from the surface and can grow to reach a critical size, potentially causing catastrophic failure of the entire structure. Thus safe operation of these structures requires careful monitoring of the initiation and growth of such defects. Ultrasonic methods using guided waves offer a reliable and cost-effective method for structural health monitoring in advanced structures. Guided waves allow for long monitoring ranges and are very sensitive to defects within their propagation path. In this work, the relevant properties of guided Lamb waves for damage detection in composite structures are investigated. An efficient numerical approach is used to determine their dispersion characteristics, and these results are compared to those from laboratory experiments. The experiments are based on a pitch-catch method, in which a pair of movable transducers is placed on one surface of the structure to induce and detect guided Lamb waves. The specific cases considered include an aluminum plate and an aluminum honeycomb sandwich panel with woven composite face sheets. In addition, a disbond of the interface between one of the face sheets and the honeycomb core of the sandwich panel is also considered, and the dispersion characteristics of the two resultant waveguides are determined. Good agreement between numerical and experimental dispersion results is found, and suggestions on the applicability of the pitch-catch system for structural health monitoring are made.

  5. Free Vibration and Hardening Behavior of Truss Core Sandwich Beam

    Directory of Open Access Journals (Sweden)

    J. E. Chen

    2016-01-01

    Full Text Available The dynamic characteristics of simply supported pyramidal truss core sandwich beam are investigated. The nonlinear governing equation of motion for the beam is obtained by using a Zig-Zag theory. The averaged equations of the beam with primary, subharmonic, and superharmonic resonances are derived by using the method of multiple scales and then the corresponding frequency response equations are obtained. The influences of strut radius and core height on the linear natural frequencies and hardening behaviors of the beam are studied. It is illustrated that the first-order natural frequency decreases continuously and the second-order and third-order natural frequencies initially increase and then decrease with the increase of strut radius, and the first three natural frequencies all increase with the rise of the core height. Furthermore, the results indicate that the hardening behaviors of the beam become weaker with the increase of the rise of strut radius and core height. The mechanisms of variations in hardening behavior of the sandwich beam with the three types of resonances are detailed and discussed.

  6. Modelling of Debond and Crack Propagation in Sandwich Structures Using Fracture and Damage Mechanics

    DEFF Research Database (Denmark)

    Berggreen, C.; Simonsen, Bo Cerup; Toernqvist, Rikard

    2003-01-01

    Skin-core de-bonding or core crack propagation will often be dominating mechanisms in the collapse modes of sandwich structures. This paper presents two different methods for prediction of crack propagation in a sandwich structure: a fracture mechanics approach, where a new mode-mix method...

  7. Failure Investigation of Debonded Sandwich Columns: An Experimental and Numerical Study

    DEFF Research Database (Denmark)

    Moslemian, Ramin; Berggreen, Christian; Carlsson, Leif A.

    2009-01-01

    Failure of compression loaded sandwich columns with an implanted through-width face/core debond is examined. Compression tests were conducted on sandwich columns containing implemented face/core debonds. The strains and out-of-plane displacements of the debonded region were monitored using the di...

  8. Research overview of design method of super light multi-hole class- honeycomb sandwich structure materials

    Directory of Open Access Journals (Sweden)

    Xiang LI

    Full Text Available With the sandwich structure materials' application and promotion in the field of engineering continuously, existing sandwich structure material gradually cannot meet the design requirements. It is very urgent to develop new sandwich structure materials of high efficiency, energy saving and easy to process. The project puts forward and constructs a new kind of class-honeycomb sandwich structure material combined with important application backgrounds that super light and high strength metal sandwich structure materials are applied into the high weight and high energy consumption equipments of automobile, aerospace and machinery and so on. This research involve: mechanical properties equivalent method for the class-honeycomb sandwich structure and its core; Strength, stiffness and inherent frequency characteristic and failure criterions of the class-honeycomb sandwich structure; based on the failure criterions constructing the multiple-constraint models of the class-honeycomb sandwich structure. The research tries to put forward a new method for innovative design of lightweight material and structure and new ideas of lightweight technology research in theory and practice.

  9. Real-time X-ray investigation of aluminum foam sandwich production

    Energy Technology Data Exchange (ETDEWEB)

    Banhart, J.; Stanzick, H. [Fraunhofer-Inst. for Advanced Materials, Bremen (Germany); Helfen, L.; Baumbach, T. [Fraunhofer-Inst. for Non-Destructive Testing, Dresden (Germany); Nijhof, K. [Honsel-Werke AG, Meschede (Germany)

    2001-06-01

    The authors study the foaming behavior of Al-based sandwich panels using X-ray radioscopy. X-ray radioscopy is a suitable tool for observing the metal foaming process in general and the production of aluminum foam sandwich panels in particular. The internal structure of the foam can be resolved clearly. (orig.)

  10. A Phloem Sandwich Unit for Observing Bark Beetles, Associated Predators, and Parasites

    Science.gov (United States)

    Donald N. Kim; Mitchel C. Miller

    1981-01-01

    This paper describes a phloem sandwich that allows observation of parent beetles, their brood, and associates within the inner bark, and permits observation of predator and parasite behavior on the bark surface. The construction of the unit permits the introduction of multiple pairs of beetles into a single sandwich.

  11. Sandwich Magnetoelectric Composites of Polyvinylidene Fluoride, Tb-Dy-Fe Alloy, and Lead Zirconate Titanate

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The novel sandwich composites were prepared by sandwiching a polyvinylidene fluoride/Tb-Dy-Fe alloy composite (PVDF/Terfenol-D) between polyvinylidene fluoride/lead zirconate titanate composites(PVDF/PZT). The maximum magnetoelectric effect voltage coefficient, (dE/dH)33max, of the sandwich composites is higher than that of three-phase composites at their own optimal loading level of Terfenol-D. This is attributed to less interface relaxations of strain and better polarization of the sandwich composites. When the volume fraction of Terfenol-D is higher than 0.10, no coupling interaction for three-phase composites could intensity, the magnetoelectric effect voltage coefficient, (dE/dH)33, of sandwich composites is higher than that of three-phase composites; at low magnetic field intensity, (dE/dH)33 of sandwich composites is lower than that of three-phase composites. At their resonance frequency, the (dE/dH)33max of the sandwich composites and the dH)33max at resonance frequency confirms the improvement of maximum magnetoelectric effect coefficient via sandwich-structured composites.

  12. PMI Foam Cored Sandwich Components Produced by Means of Different Manufacturing Methods

    Institute of Scientific and Technical Information of China (English)

    Leonhard Maier; HU Pei; Herman Seibert

    2006-01-01

    The paper introduced the structural applications with PMI (Polymethacrylimide) foams in sandwich components for rotor craft, launching vehicle and civil aircraft and discuss some typically used manufacturing methods, such as e. g.in-mould pressing, autoclave curing and resin infusion. The advantages of foam-cored sandwich design versus honeycombcored design will be discussed, focussing on manufacturing costs.

  13. Failure Investigation of Debonded Sandwich Columns: An Experimental and Numerical Study

    DEFF Research Database (Denmark)

    Moslemian, Ramin; Berggreen, Christian; Carlsson, Leif A.

    2009-01-01

    Failure of compression loaded sandwich columns with an implanted through-width face/core debond is examined. Compression tests were conducted on sandwich columns containing implemented face/core debonds. The strains and out-of-plane displacements of the debonded region were monitored using the di...

  14. Mixed mode fracture toughness characterization of sandwich interfaces using the modified TSD specimen

    DEFF Research Database (Denmark)

    Berggreen, Christian; Andreasen, J.H.; Carlsson, L.A.;

    2009-01-01

    An extensive parametric analysis shows that the modified Tilted Sandwich Debond (TSD) specimen provides a methodology for characterization of the face/core fracture resistance over a range of mode-mixities. A pilot experimental mixed mode characterization of the fracture toughness of sandwich spe...

  15. Experimental validation of the Higher-Order Theory approach for sandwich panels with flexible core materials

    NARCIS (Netherlands)

    Straalen, IJ.J. van

    2000-01-01

    During tthe 1990's the higher-order theory was developed by Frostig to enable detailed stress analyses of sandwich panel structures. To investigate the potentials of this approach experiments are performed on sandwich panels made of thin steel faces and mineral wool or polystyrene core material. A p

  16. Weld nugget formation in resistance spot welding of new lightweight sandwich material

    DEFF Research Database (Denmark)

    Sagüés Tanco, J.; Nielsen, Chris Valentin; Chergui, Azeddine

    2015-01-01

    Weldability of a new lightweight sandwich material, LITECOR®, by resistance spot welding is analyzed by experiments and numerical simulations. The spot welding process is accommodated by a first pulse squeezing out the non-conductive polymer core of the sandwich material locally to allow metal–me...

  17. Robust and Air-Stable Sandwiched Organo-Lead Halide Perovskites for Photodetector Applications

    KAUST Repository

    Mohammed, Omar F.

    2016-02-25

    We report the simplest possible method to date for fabricating robust, air-stable, sandwiched perovskite photodetectors. Our proposed sandwiched structure is devoid of electron or hole transporting layers and also the expensive electrodes. These simpler architectures may have application in the perovskite-only class of solar cells scaling up towards commercialization.

  18. Innovative sandwich concepts open up potential for flat structures. Function-integrated lightweight design; Sandwich-Strukturen fuer den funktionsintegrierten Leichtbau. Fahrzeugleichtbau

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, Gerhard; Friedrich, Horst E. [DLR Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Stuttgart (Germany). Inst. fuer Fahrzeugkonzepte; Kuppinger, Jan [Fraunhofer-Institut fuer Chemische Technologie (ICT), Pfinztal (Germany). Abt. Polymer-Engineering; Henning, Frank [Fraunhofer-Institut fuer Chemische Technologie (ICT), Pfinztal (Germany). Abt. Polymer-Engineering; DLR Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Stuttgart (Germany). Kompetenzzentrum; Karlsruher Innovationsclusters ' Technologien fuer den hybriden Leichtbau' (Germany)

    2009-07-01

    Sandwich structures make it possible to achieve an optimum combination of material, form and functional lightweight design. Vehicle weight is reduced and resources are saved. However, such solutions can only be used when the overall concept is cost-effective. For this reason, various DLR and Fraunhofer institutes are currently working on new and cost-effective sandwich structures within the 'Competence Centre for Automotive Lightweight Technology' to further exploit this construction method for flat structures. (orig.)

  19. A Novel Sandwich-type Dinuclear Complex for High-capacity Hydrogen Storage%A Novel Sandwich-type Dinuclear Complex for High-capacity Hydrogen Storage

    Institute of Scientific and Technical Information of China (English)

    朱海燕; 陈元振; 李赛; 曹秀贞; 柳永宁

    2012-01-01

    From density functional theory (DFT) calculations, we predicted that the sandwich-type dinuclear organometallic compounds Cpffi2 and Cp2Sc2 can adsorb up to eight hydrogen molecules respectively, corresponding to a high gravimetric storage capacity of 6.7% and 6.8% (w), respectively. These sandwich-type organometallocenes proposed in this work are favorable for reversible adsorption and desorption of hydrogen at ambient conditions.

  20. redMaPPer IV: Photometric Membership Identification of Cluster Galaxies with 1% Precision

    CERN Document Server

    Rozo, Eduardo; Becker, Matthew; Reddick, Rachel M; Wechsler, Risa H

    2014-01-01

    In order to study the galaxy population of galaxy clusters with photometric data one must be able to accurately discriminate between cluster members and non-members. The redMaPPer cluster finding algorithm treats this problem probabilistically. Here, we utilize SDSS and GAMA spectroscopic membership rates to validate the redMaPPer membership probability estimates for clusters with $z\\in[0.1,0.3]$. We find small - but correctable - biases, sourced by three different systematics. The first two were expected a priori, namely blue cluster galaxies and correlated structure along the line of sight. The third systematic is new: the redMaPPer template fitting exhibits a non-trivial dependence on photometric noise, which biases the original redMaPPer probabilities when utilizing noisy data. After correcting for these effects, we find exquisite agreement ($\\approx 1\\%$) between the photometric probability estimates and the spectroscopic membership rates, demonstrating that we can robustly recover cluster membership est...

  1. 76 FR 59664 - Membership of the Defense Contract Audit Agency Senior Executive Service Performance Review Boards

    Science.gov (United States)

    2011-09-27

    ... Service (SES) performance appraisals and make recommendations to the Director, DCAA, regarding final... this notice. FOR FURTHER INFORMATION CONTACT: Sandra L. Burrell, Chief, Human Resources Management... of the Secretary Membership of the Defense Contract Audit Agency Senior Executive Service...

  2. 77 FR 52707 - Notice of Membership of the Performance Review Board

    Science.gov (United States)

    2012-08-30

    ... the initial appraisal of each senior executive's performance, along with any comments by that senior... INFORMATION CONTACT: Andrea Burckman, Director, Executive Resources Division, Human Capital and Client... Notice of Membership of the Performance Review Board AGENCY: Office of Management, Department...

  3. 76 FR 58559 - Notice of Senior Executive Service Performance Review Board Membership

    Science.gov (United States)

    2011-09-21

    ... Performance Review Board which oversees the evaluation of performance appraisals of Senior Executive Service.... Wells, Deputy Commissioner for Human Resources. BILLING CODE 4191-02-P ... ADMINISTRATION Notice of Senior Executive Service Performance Review Board Membership AGENCY: Social...

  4. 75 FR 57906 - Membership of the Defense Contract Audit Agency Senior Executive Service Performance Review Boards

    Science.gov (United States)

    2010-09-23

    ... appraisals and make recommendations to the Director, DCAA, regarding final performance ratings and... INFORMATION CONTACT: Sandra L. Burrell, Chief, Human Resources Management Division, Defense Contract Audit... of the Secretary Membership of the Defense Contract Audit Agency Senior Executive Service...

  5. Change and stability in childhood clique membership, isolation from cliques, and associated child characteristics.

    Science.gov (United States)

    Witvliet, Miranda; van Lier, Pol A C; Cuijpers, Pim; Koot, Hans M

    2010-01-01

    This study explored the role of clique membership and clique isolation in children's psychosocial adjustment. We identified change and stability in early elementary school clique membership and investigated behavioral characteristics related to this change and stability. Participants were first-grade pupils (N = 300), followed over a 1-year period. Clique membership was identified through social network analysis. Differences between children with a stable versus changing clique membership status were tested using peer nominations and teacher ratings. Clique members were better adjusted than nonclique members. Externalizing behavior, less prosocial behavior, and low social preference preceded clique estrangement. Stable-isolates increased in externalizing behavior, whereas children who became part of a dyad or included in a clique showed a decrease in externalizing behavior.

  6. 78 FR 10104 - Watermelon Research and Promotion Plan; Importer Membership Requirements

    Science.gov (United States)

    2013-02-13

    ...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 1210 Watermelon Research and Promotion Plan; Importer Membership Requirements AGENCY: Agricultural Marketing Service, USDA. ACTION: Proposed rule. SUMMARY: This rule proposes to amend the Watermelon Research and Promotion Plan (Plan)...

  7. The impact of ignoring multiple membership data structures in multilevel models.

    Science.gov (United States)

    Chung, Hyewon; Beretvas, S Natasha

    2012-05-01

    This study compared the use of the conventional multilevel model (MM) with that of the multiple membership multilevel model (MMMM) for handling multiple membership data structures. Multiple membership data structures are commonly encountered in longitudinal educational data sets in which, for example, mobile students are members of more than one higher-level unit (e.g., school). While the conventional MM requires the user either to delete mobile students' data or to ignore prior schools attended, MMMM permits inclusion of mobile students' data and models the effect of all schools attended on student outcomes. The simulation study identified underestimation of the school-level predictor coefficient, as well as underestimation of the level-two variance component with corresponding overestimation of the level-one variance when multiple membership data structures were ignored. Results are discussed along with limitations and ideas for future MMMM methodological research as well as implications for applied researchers.

  8. 78 FR 64408 - Watermelon Research and Promotion Plan; Importer Membership Requirements and Referendum Order

    Science.gov (United States)

    2013-10-29

    ... From the Federal Register Online via the Government Publishing Office #0; #0;Proposed Rules #0...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 1210 Watermelon Research and Promotion Plan; Importer Membership Requirements and Referendum Order AGENCY: Agricultural Marketing Service...

  9. 8 CFR 245a.14 - Application for class membership in the CSS, LULAC, or Zambrano lawsuit.

    Science.gov (United States)

    2010-01-01

    ... Equity (LIFE) Act Legalization Provisions § 245a.14 Application for class membership in the CSS, LULAC... alien must provide with the application for LIFE Legalization evidence establishing that, before...

  10. The Prospects of Membership in International Organizations: The Case of Kosovo

    Directory of Open Access Journals (Sweden)

    Ardian Emini

    2016-12-01

    Full Text Available The purpose of this paper is to analyze the perspective of Kosovo and its membership in international organizations. There are three pillars upon which the analysis of the paper is built. Initially the general question of theoretical frameworks in general the organizations which focus on the elaboration of the very concept of statehood and state-building in general and specifically on Kosovo. The final section deals with a range of behaviors and initiatives of countries in general and the challenges for membership in international organizations. With the aim of contextualizing the subject, the paper focuses on the case of Kosovo state and membership in international organizations with a view to strengthening the international subjectivity and security in the international arena. Finally, the paper concludes that the importance of the accession countries, namely Kosovo's membership in international organizations, and the use of multilateral diplomacy are vital to their safety and welfare.

  11. 77 FR 7133 - Advisory Committee on Supply Chain Competitiveness Solicitation of Nominations for Membership

    Science.gov (United States)

    2012-02-10

    ... International Trade Administration Advisory Committee on Supply Chain Competitiveness Solicitation of..., Including Ports, To Apply for Membership on the Advisory Committee on Supply Chain Competitiveness. SUMMARY... or entities, including ports, to serve as members of the Advisory Committee on Supply...

  12. Influence of Si buffer layer on the giant magnetoresistance effect in Co/Cu/Co sandwiches

    Institute of Scientific and Technical Information of China (English)

    李冠雄; 沈鸿烈; 沈勤我; 李铁; 邹世昌

    2000-01-01

    The Co/Cu/Co sandwiches with a semiconductor Si buffer layer were prepared by high vacuum electron-beam evaporation. The influence of the Si buffer layer with different thickness on the giant magnetoresistance (GMR) effect in the Co/Cu/Co sandwiches was investigated. It was found that the GMR showed an obvious anisotropy when the thickness of Si buffer layer was larger than or equal to 0.9 nm, and that the GMR was basically isotropic with an Si buffer layer thinner than 0.9 nm. The anisotropic behavior of GMR can be ascribed to the in-plane magnetic anisotropy in the sandwiches. Due to the interdiffusion at the Si buffer/Co interface, a Co2Si interface layer with a good (301) texture formed and induced the in-plane magnetic anisotropy in the sandwiches. The dependence of the crystalline texture of the sandwiches on the thickness of Si buffer layer was also studied.

  13. Unidirectional cloning by cleaving heterogeneous sites with a single sandwiched zinc finger nuclease.

    Science.gov (United States)

    Shinomiya, Kazuki; Mori, Tomoaki; Aoyama, Yasuhiro; Sera, Takashi

    2011-11-04

    We previously developed a novel type of zinc finger nucleases (ZFNs), sandwiched ZFNs that can discriminate DNA substrates from cleavage products and thus cleave DNA much more efficiently than conventional ZFNs as well as perform with multiple turnovers like restriction endonucleases. In the present study, we used the sandwiched ZFN to unidirectionally clone exogenous genes into target vectors by cleaving heterogeneous sites that contained heterogeneous spacer DNAs between two zinc-finger protein binding sites with a single sandwiched ZFN. We demonstrated that the sandwiched ZFN cleaved a 40-fold excess of both insert and vector plasmids within 1h and confirmed by sequencing that the resulting recombinants harbored the inserted DNA fragment in the desired orientation. Because sandwiched ZFNs can recognize and cleave a variety of long (≥ 26-bp) target DNAs, they may not only expand the utility of ZFNs for construction of recombinant plasmids, but also serve as useful meganucleases for synthesis of artificial genomes.

  14. An Optimum Analysis Method of Sandwich Structures Made from Elastic-viscoelastic Materials

    Institute of Scientific and Technical Information of China (English)

    CHEN Ying-bo; XIA Yu; REN Zhi-gang; LU Zhe-an; WANG Er-lei

    2004-01-01

    Due to a viscoelastic damping middle layer,sandwich structures have the capacity of energy consumption.In this paper,we describe the frequency-dependent property of viscoelastic materials using complex modulus model,and iterative modal strain energy method and iterative complex eigenvalue method are presented to obtain frequency and loss factor of sandwich structures.The two methods are effective and exact for the large-scale complex composite sandwich structures.Then an optimum analysis method is suggested to apply to sandwich structures.Finally,as an example,an optimum analysis of a clamped-clamped sandwich beams is conducted,theoretical closed-form solution and numerical predictions are studied comparatively,and the results agree well.

  15. Natural Cork Agglomerate Employed as an Environmentally Friendly Solution for Quiet Sandwich Composites

    Science.gov (United States)

    Sargianis, James; Kim, Hyung-ick; Suhr, Jonghwan

    2012-01-01

    Carbon fiber-synthetic foam core sandwich composites are widely used for many structural applications due to their superior mechanical performance and low weight. Unfortunately these structures typically have very poor acoustic performance. There is increasingly growing demand in mitigating this noise issue in sandwich composite structures. This study shows that marrying carbon fiber composites with natural cork in a sandwich structure provides a synergistic effect yielding a noise-free sandwich composite structure without the sacrifice of mechanical performance or weight. Moreover the cork-core sandwich composites boast a 250% improvement in damping performance, providing increased durability and lifetime operation. Additionally as the world seeks environmentally friendly materials, the harvesting of cork is a natural, renewable process which reduces subsequent carbon footprints. Such a transition from synthetic foam cores to natural cork cores could provide unprecedented improvements in acoustic and vibrational performance in applications such as aircraft cabins or wind turbine blades. PMID:22574250

  16. Structural Behaviour of Precast Lightweight Foamed Concrete Sandwich Panel under Axial Load: An Overview

    Directory of Open Access Journals (Sweden)

    Suryani Samsudin

    2013-02-01

    Full Text Available The development of precast sandwich concrete has gained acceptance worldwide in conjunction with the Industrial Building System (IBS.  The advancement and improvement of using wall panel has gone through a lot of achievements through the last decade. The usage of precast lightweight sandwich panel has become the alternative to conventional construction using brick wall. The usage of this panel system contributes to a sustainable and environmental friendly construction.  This paper presents an overview of the latest development in precast concrete sandwich panel as an IBS. The purpose of this paper is to provide comprehensive information on latest research development of sandwich panel for building construction purposes. The information on sandwich panel’s composition, material, properties, strength, availability, and its usage as structural element are reported.  An innovative concept used in the design of these systems and the use of lightweight materials is also discussed.

  17. Analysis and Behaviour of Sandwich Panels with Profiled Metal Facings under Transverse Load

    Directory of Open Access Journals (Sweden)

    M. Budescu

    2004-01-01

    Full Text Available Sandwich panels with thin steel facings and polyurethane core combine the load-carrying capacity of metal facings and protection functions with core properties. The core separates the two facings and keeps them in a stable condition, transmits shear between external layers, provides most of the shear rigidity and occasionally makes of useful contribution to the bending stiffness of the sandwich construction as a whole [1]. An experimental program on sandwich panels has been organized to prove that the mechanical properties of core and interface satisfy the load-carrying requirements for structural sandwich panels. The analysis of sandwich panels with deep profiles facings for cladding elements, respectively the roof constructions, has been carried out according to the European design norms [1], [5].

  18. Computed tomography with single-shot dual-energy sandwich detectors

    Science.gov (United States)

    Kim, Seung Ho; Youn, Hanbean; Kim, Daecheon; Kim, Dong Woon; Jeon, Hosang; Kim, Ho Kyung

    2016-03-01

    Single-shot dual-energy sandwich detector can produce sharp images because of subtraction of images from two sub-detector layers, which have different thick x-ray converters, of the sandwich detector. Inspired by this observation, the authors have developed a microtomography system with the sandwich detector in pursuit of high-resolution bone-enhanced small-animal imaging. The preliminary results show that the bone-enhanced images reconstructed with the subtracted projection data are better in visibility of bone details than the conventionally reconstructed images. In addition, the bone-enhanced images obtained from the sandwich detector are relatively immune to the artifacts caused by photon starvation. The microtomography with the single-shot dual-energy sandwich detector will be useful for the high-resolution bone imaging.

  19. Design of a decentralized asynchronous group membership protocol and an implementation of its communications layer

    OpenAIRE

    Pires, Fernando Jorge.

    1993-01-01

    Approved for public release; distribution is unlimited. For development of group-oriented distributed applications, a group membership protocol provides the mechanisms to dynamically adapt to changes in the membership, ensuring consistent views among all members of the group. This is achieved, by executing a distributed script, that implements a protocol, at each member to maintain a sequence of identical views, in spite of continuous changes, either voluntary or due to failure, to the mem...

  20. Identifying groups at risk for 1-year membership termination from a fitness center at enrollment

    Directory of Open Access Journals (Sweden)

    Stephanie A. Hooker

    2016-12-01

    Full Text Available The vast majority of Americans do not engage in adequate regular physical activity despite its well-known health benefits. Even when individuals attempt to become more active by joining a fitness center, estimates suggest that nearly half terminate their membership within the first 6 months. A better understanding of who is at risk for early membership termination upon joining may help researchers develop targeted interventions to improve the likelihood that individuals will successfully maintain memberships and physical activity. This study's purpose was to identify, based on a wellness assessment (WA used in fitness centers, individuals at risk for fitness membership termination prior to 1-year. Center members (N = 441; Mage = 41.9, SD = 13.1; 74.4% female completed a comprehensive WA of stress, life satisfaction, physical fitness, metabolic health, and sleep quality at the beginning of their memberships and were followed for one year. Latent class analyses utilized the WA to identify four groups: (a healthy, (b unhealthy, (c poor psychological wellness, and (d poor physical wellness. Participants in the poor psychological wellness group (OR = 2.24, p = 0.007 and the unhealthy group (OR = 2.40, p = 0.037 were significantly more likely to terminate their memberships at 1-year as compared to the healthy group. Participants with poor physical wellness visited the fitness center less frequently than healthy participants (p < 0.01. Results suggest that poor psychological wellness is a risk factor for terminating memberships, whereas poor physical wellness is not. Future studies should replicate these latent classes and develop targeted interventions to address psychological wellness as a method to improve fitness membership retention.