bluuebunny/crossref_metadata_2025 huggingface dataset:
In Situ Thermal Transmittance Measurements for Investigating Differences between Wall Models and Actual Building Performance
Authors: Evangelisti Luca , Guattari Claudia , Gori Paola , Vollaro Roberto
Published: August 2015

An accurate assessment of a building’s wall performance, defined through the thermal transmittance, is essential to compute the annual energy consumption. Analyzing opaque surfaces, the heat transfer across walls can be modeled by an electro-thermal analogy, based on resistors series, crossed by a one-dimensional heat flow. This analogy is well established and it refers to stratigraphy composed of homogeneous materials. When dealing with inhomogeneous materials, possibly including hollow bricks, the wall’s thermal transmittance is evaluated by means of an effective conductance. However, in order to verify the theoretical models effectiveness, a comparison with in situ measurements is needed. In this paper, three building walls characterized by different stratigraphy have been analyzed; by employing a heat flow meter investigation. Measurements results and estimated thermal transmittance values—calculated applying the standard UNI EN ISO 6946—have been compared.
Towards a Bioeconomy in Europe: National, Regional and Industrial Strategies
Authors: De Besi Matteo , McCormick Kes
Published: August 2015

Establishing an advanced European bioeconomy is an important step in achieving the transition towards sustainable development and away from fossil fuels. The bioeconomy can be defined as an economy based on the sustainable production and conversion of renewable biomass into a range of bio-based products, chemicals, and energy. Several strategies have been produced in Europe from different perspectives that outline visions, intentions, and recommendations for the transition to a bioeconomy. An analysis of twelve of these strategies was conducted using a meta-analytical framework. This paper outlines the results of this study covering national, regional, and industrial perspectives on the bio-based economy in Europe. The analysis shows that a common direction for the bioeconomy, based on research and technological innovation in the various applications of biotechnology, is developing in Europe. It highlights the important role that the regional level will play in facilitating collaborations between industries and research institutions needed to foster innovation and optimize the use of biomass. The analysis also identifies that the development of European bio-based product markets are needed for bioeconomy expansion. However, the transition needs to have a lifecycle perspective in order to ensure that an economy founded on biomass is sustainable and equitable.
Evaluation of Economic Efficiency of Apple Orchard Investments
Authors: Badiu Dorin , Arion Felix , Muresan Iulia , Lile Ramona , Mitre Viorel
Published: August 2015

The tree-growing sector is considered to be an important supplier of food and raw material for industry worldwide. Increasingly competitive decisions regarding international investment in orchards depend on business analysis. This study compares three apple orchards situated in Cluj-Napoca, on the Eastern limits of the Transylvanian Plain, Romania. While the climatic and soil conditions are relatively consistent among the three orchards, the technical and economic results (expressed in hectares) vary due to the use of three different technological systems of apple production: extensive, intensive, and super-intensive. The study compares the life cycle, starting with age of fructification, production level (quantity and quality), costs (investment and production costs—divided into material costs, mechanical costs, human costs, and overhead costs), income, profit (including rate of profit), and investment efficiency: Net Present Value (NPV), Internal Rate of Return (IRR), and Payback Period (PP). It was observed that the most economically efficient technological system in terms of investments is the super-intensive one, with a higher production level, a higher share of Extra Class apples, and a younger age of initial fructification. However certain inconveniences of this system—such as a more expensive investment, a higher cost of running the business throughout the year, and a reduced life cycle—cannot be ignored.
Urban Floods in Lowlands—Levee Systems, Unplanned Urban Growth and River Restoration Alternative: A Case Study in Brazil
Authors: Miguez Marcelo , Veról Aline , De Sousa Matheus , Rezende Osvaldo
Published: August 2015

The development of cities has always had a very close relation with water. However, cities directly impact land use patterns and greatly change natural landscapes, aggravating floods. Considering this situation, this paper intends to discuss lowland occupation and city sustainability in what regards urban stormwater management, fluvial space, and river restoration, aiming at minimizing flood risks and improving natural and built environment conditions. River plains tend to be attractive places for a city to grow. From ancient times, levees have been used to protect lowland areas along major watercourses to allow their occupation. However, urban rivers demand space for temporary flood storage. From a systemic point of view, levees along extensive river reaches act as canalization works, limiting river connectivity with flood plains, rising water levels, increasing overtopping risks and transferring floods downstream. Departing from this discussion, four case studies in the Iguaçu-Sarapuí River Basin, a lowland area of Rio de Janeiro State, Brazil, are used to compose a perspective in which the central point refers to the need of respecting watershed limits and giving space to rivers. Different aspects of low-lying city planning are discussed and analyzed concerning the integration of the built and natural environments.
Scaled Experimental Study on Maximum Smoke Temperature along Corridors Subject to Room Fires
Authors: Xing Zheli , Mao Jinfeng , Huang Yuliang , Zhou Jin , Mao Wei , Deng Feifan
Published: August 2015

In room–corridor building geometry, the corridor smoke temperature is of great importance to fire protection engineering as indoor fires occur. Theoretical analysis and a set of reduced-scale model experiments were performed, and a virtual fire model was proposed, to investigate the correlations between the maximum smoke temperature in corridors and the smoke temperature in rooms. The results show that the dimensionless virtual fire heat release rate (HRR) is characterized by quadratic-polynomial of the dimensionless smoke temperature in fire rooms. The dimensionless distance from a virtual fire source to the corridor ceiling varies linearly with the dimensionless smoke temperature in a room. Results of multiple regression indicate that, at the impingement area of virtual fire, the dimensionless maximum smoke temperature in corridors is only related to the dimensionless virtual fire HRR; in the non-impingement area of a virtual fire, the dimensionless maximum smoke temperature in corridors is a function of the dimensionless virtual fire HRR and dimensionless longitude distance. The viscosity and conduction exhibit an insignificant impact on the maximum temperature in the corridor. Through replacing the parameters of virtual fire with the dimensionless smoke temperature in fire rooms, the correlations between dimensionless maximum temperature in corridors and the dimensionless smoke temperature in fire rooms were proposed.
Botulinum Toxin for Neuropathic Pain: A Review of the Literature
Authors: Oh Hyun-Mi , Chung Myung
Published: August 2015

Botulinum neurotoxin (BoNT), derived from Clostridium botulinum, has been used therapeutically for focal dystonia, spasticity, and chronic migraine. Its spectrum as a potential treatment for neuropathic pain has grown. Recent opinions on the mechanism behind the antinociceptive effects of BoNT suggest that it inhibits the release of peripheral neurotransmitters and inflammatory mediators from sensory nerves. There is some evidence showing the axonal transport of BoNT, but it remains controversial. The aim of this review is to summarize the experimental and clinical evidence of the antinociceptive effects, mechanisms, and therapeutic applications of BoNT for neuropathic pain conditions, including postherpetic neuralgia, complex regional pain syndrome, and trigeminal neuralgia. The PubMed and OvidSP databases were searched from 1966 to May 2015. We assessed levels of evidence according to the American Academy of Neurology guidelines. Recent studies have suggested that BoNT injection is an effective treatment for postherpetic neuralgia and is likely efficient for trigeminal neuralgia and post-traumatic neuralgia. BoNT could also be effective as a treatment for diabetic neuropathy. It has not been proven to be an effective treatment for occipital neuralgia or complex regional pain syndrome.
Zearalenone in the Intestinal Tissues of Immature Gilts Exposed per os to Mycotoxins
Authors: Zielonka Łukasz , Waśkiewicz Agnieszka , Beszterda Monika , Kostecki Marian , Dąbrowski Michał , Obremski Kazimierz , Goliński Piotr , Gajęcki Maciej
Published: August 2015

Zearalenone and its metabolites, α-zearalenol and β-zearalenol, demonstrate estradiol-like activity and disrupt physiological functions in animals. This article evaluates the carryover of zearalenone and its selected metabolites from the digesta to intestinal walls (along the entire intestines) in pre-pubertal gilts exposed to low doses of zearalenone over long periods of time. The term “carryover” describes the transfer of mycotoxins from feed to edible tissues, and it was used to assess the risk of mycotoxin exposure for consumers. The experimental gilts with body weight of up to 25 kg were per os administered zearalenone at a daily dose of 40 μg/kg BW (Group E, n = 18) or placebo (Group C, n = 21) over a period of 42 days. In the first weeks of exposure, the highest values of the carryover factor were noted in the duodenum and the jejunum. In animals receiving pure zearalenone, the presence of metabolites was not determined in intestinal tissues. In the last three weeks of the experiment, very high values of the carryover factor were observed in the duodenum and the descending colon. The results of the study indicate that in animals exposed to subclinical doses of zearalenone, the carryover factor could be determined by the distribution and expression of estrogen receptor beta.
Spatiotemporal Dynamics of Microcystin Variants and Relationships with Environmental Parameters in Lake Taihu, China
Authors: Su Xiaomei , Xue Qingju , Steinman Alan , Zhao Yanyan , Xie Liqiang
Published: August 2015

Excessive anthropogenically-caused nutrient loading from both external and internal sources has promoted the growth of cyanobacteria in Lake Taihu from 2005 to 2014, suggesting increased production and release of cyanotoxins. In order to explain the spatial distribution and temporal variation of microcystins (MCs), the intracellular concentrations of MCs (MC-LR, -RR and -YR, L, R and Y are abbreviations of leucine, arginine and tyrosine) were monitored monthly from July 2013 to June 2014. Three MC variants are present simultaneously in Lake Taihu; the MC-LR and -RR variants were dominant (accounting for 40% and 39% of the total), followed by MC-YR (21%). However, MC-YR accounted for a higher proportion in colder months, especially in March. The highest concentrations of intracellular MCs were found in July and October when cyanobacteria cell density also reached the maximum. The average concentrations of MC-LR, -RR and -YR in July were 4.69, 4.23 and 2.01 μg/L, respectively. In terms of the entire lake, toxin concentrations in northern parts were significantly higher than the eastern part in summer, when MC concentrations were several times higher than the guideline value by WHO throughout much of Lake Taihu. Results from correlation and redundancy analysis (RDA) showed that total MCs, including all variants, were strongly and positively correlated with cyanobacteria cell density, water temperature, total phosphorus (TP) and pH, whereas each variant had different correlation coefficients with each of the considered environmental variables. MC-RR showed a stronger relationship with temperature, in contrast to MC-YR and -LR. Dissolved inorganic carbon (DIC) showed a negative relationship with each variant, suggesting that rising DIC concentrations may inhibit cyanobacterial growth and thereby reduce MC production in the future.
Bacterial Loads on Skin of Unclipped Gluteal Sites Following Treatment with 70% Isopropyl Alcohol-Soaked Swabs in Dairy Cows
Authors: Cockcroft Peter , Redfern Helen
Published: August 2015

The aim of this study was to compare the bacterial load of unclipped gluteal skin in dairy cows following either no treatment or treatment with a standard 70% isopropyl alcohol-based skin treatment protocol. Twenty Holstein-Friesian dairy cows from a commercial dairy herd in Cambridgeshire, England, were used in this randomised, blinded, controlled study. On each of the experimental cows an area of unclipped gluteal skin on one side of the pelvis was treated with swabs soaked in 70% isopropyl alcohol-based using a standard protocol and a contra-lateral area of skin was left untreated as a control. All the experimental skin sites were sampled using a swab followed by bacterial culture and quantitative analysis of bacterial load. There was a statistically significant decrease in the bacterial colony forming units per mL for the isopropyl-alcohol treatment group when compared to the control group (p ≤ 0.01). There was a 58% reduction in the median bacterial load of the treated sites when compared to the bacterial load of the untreated sites. This study has demonstrated that the treatment protocol will reduce the skin bacterial load.
Evaluating Groundwater Management Sustainability under Limited Data Availability in Semiarid Zones
Authors: Senent-Aparicio Javier , Pérez-Sánchez Julio , García-Aróstegui José , Bielsa-Artero Alicia , Domingo-Pinillos Juan
Published: August 2015

In recent years, many researchers have devoted their efforts to finding an objective measurement of sustainability by developing evaluation tools based on sustainability indices. These indexes not only reveal the current state of water resources in a given area but also contribute to the development and implementation of effective sustainable water management and decision-making. The great disadvantage of these indices is that for proper application, a number of variables are necessary and they are usually not available in data-scarce aquifers. This study was designed to evaluate sustainability in groundwater resource management in an aquifer in a semiarid zone, using readily available parameters and under a pressure-state-response framework. This methodology has been applied to an aquifer in Southeast Spain with satisfactory results, since the indicators that were evaluated reflect the two main problems that hinder sustainable resource management: the contamination of groundwater by intensive local farming; and the need for external inputs from other basins to alleviate water stress. Therefore, the methodology used can be replicated in other areas with similar characteristics to those of the case study.
Agricultural Rivers at Risk: Dredging Results in a Loss of Macroinvertebrates. Preliminary Observations from the Narew Catchment, Poland
Authors: Grygoruk Mateusz , Frąk Magdalena , Chmielewski Aron
Published: August 2015

Ecosystem deterioration in small lowland agricultural rivers that results from river dredging entails a significant threat to the appropriate ecohydrological conditions of these water bodies, expressed as homogenization of habitats and loss of biodiversity. Our study was aimed at a comparison of abundance and taxonomic structure of bottom-dwelling macroinvertebrates in dredged and non-dredged stretches of small lowland rivers and tributaries of the middle Narew River, namely: Czaplinianka, Turośnianka, Dąb, and Ślina. The experimental setup was (1) to collect samples of the bottom material from the river stretches that either persisted in a non-modified state (dredging was not done there in the last few years) or had been subjected to river dredging in the year of sampling; and (2) to analyze the abundance and taxonomic structure of macroinvertebrates in the collected samples. The study revealed that at the high level of statistical significance (from p = 0.025 to p = 0.001), the total abundance of riverbed macroinvertebrates in the dredged stretches of the rivers analyzed was approximately 70% lower than in non-dredged areas. We state that the dredging of small rivers in agricultural landscapes seriously affects their ecological status by negatively influencing the concentrations and species richness of benthic macroinvertebrates.
Fertility Preservation in Reproductive-Age Women Facing Gonadotoxic Treatments
Authors: Roberts J. , Ronn R. , Tallon N. , Holzer H.
Published: August 2015

Background: Advancements in the treatments for cancer and autoimmune and other hematologic conditions continue to improve survival and cure rates. Despite those changes, various gonadotoxic agents and other treatments can still compromise the future fertility of many women. Progress in medical and surgical reproductive technologies has helped to offset the reproductive consequences of the use of gonadotoxic therapies, and allows for future fertility and normal pregnancy. Methods: A review of the literature was performed to outline the pathophysiology of gonadotoxicity from various treatments. The success of fertility preservation, fertility sparing, and cryopreservation options are reviewed. Barriers and facilitators to referral and oncofertility treatment in Canada are also outlined. Results: According to the quality of the evidence, recommendations are made for fertility assessment, patient referral, cryopreservation, and other assisted reproductive technologies. Conclusions: To ensure ongoing fertility in women undergoing gonadotoxic treatments, assisted reproductive technologies can be combined with a multidisciplinary approach to patient assessment and referral.
Revealing a Cancer Diagnosis to Patients: Attitudes of Patients, Families, Friends, Nurses, and Physicians in Lebanon—Results of a Cross-Sectional Study
Authors: Farhat F. , Othman A. , el Baba G. , Kattan J.
Published: August 2015

Background: Disclosure of a cancer diagnosis to patients is a major problem for physicians in Lebanon. Our survey aimed to identify the attitudes of patients, families and friends, nurses, and physicians regarding disclosure of a cancer diagnosis. Methods: Study participants included 343 physicians, nurses, cancer patients, families, and friends from clinics in two major hospitals in Lebanon. All completed a 29-item questionnaire that assessed, by demographic group, the information provided about cancer, opinions about the disclosure of the diagnosis to cancer patients, perceived consequences to patients, and the roles of family, friends, and religion. Results: Overall, 7.8% of the patients were convinced that cancer is incurable. Nearly 82% preferred to be informed about their diagnosis. Similarly, 83% of physicians were in favour of disclosing a cancer diagnosis to their patients. However, only 14% of the physicians said that they revealed the truth to the patients themselves, with only 9% doing so immediately after confirmation of the diagnosis. Disclosure of a cancer diagnosis was preferred before the start of the treatment by 59% of the patients and immediately after confirmation of the diagnosis by 72% of the physicians. Overall, 86% of physicians, 51% of nurses, and 69% of patients and their families believed that religion helped with the acceptance of a cancer diagnosis. A role for family in accepting the diagnosis was reported by 74% of the patients, 56% of the nurses, and 88% of the physicians. All participants considered that fear was the most difficult feeling (63%) experienced by cancer patients, followed by pain (29%), pity (8%), and death (1%), with no statistically significant difference between the answers given by the participant groups. Conclusions: The social background in Lebanese society is the main obstacle to revealing the truth to cancer patients. Lebanese patients seem to prefer direct communication of the truth, but families take the opposite approach. Physicians also prefer to communicate the reality of the disease at the time of diagnosis, but in actuality, they instead disclose it progressively during treatment. Faith is helpful for acceptance of the diagnosis, and families play a key role in the support of the patients. An open discussion involving all members of society is necessary to attain a better understanding of this issue and to promote timely disclosure of a cancer diagnosis.
Increased Treatment-Related Toxicity Subsequent to an Anti–PD-1 Agent
Authors: Khoja Leila , Butler Marcus Ortho , Chappell Mary Anne , Hogg David , Joshua Anthony
Published: August 2015

The approval of ipilimumab [...]
Ready or Not? Lung Cancer Diagnosis in 2015
Authors: Jao K. , Labbe C. , Leighl N.B.
Published: August 2015

Lung cancer remains a significant health issue in Canada, with more than 26,000 new cases reported in 2014 [...]
BRCA1/2 Population Screening: Embracing the Benefits
Authors: Plon S.E.
Published: August 2015

Whether all adult Ashkenazi women should be offered population screening for recurrent [...]
The Nanomaterial Data Curation Initiative: A collaborative approach to assessing, evaluating, and advancing the state of the field
Authors: Hendren Christine Ogilvie , Powers Christina M , Hoover Mark D , Harper Stacey L
Published: August 2015

The Nanomaterial Data Curation Initiative (NDCI), a project of the National Cancer Informatics Program Nanotechnology Working Group (NCIP NanoWG), explores the critical aspect of data curation within the development of informatics approaches to understanding nanomaterial behavior. Data repositories and tools for integrating and interrogating complex nanomaterial datasets are gaining widespread interest, with multiple projects now appearing in the US and the EU. Even in these early stages of development, a single common aspect shared across all nanoinformatics resources is that data must be curated into them. Through exploration of sub-topics related to all activities necessary to enable, execute, and improve the curation process, the NDCI will provide a substantive analysis of nanomaterial data curation itself, as well as a platform for multiple other important discussions to advance the field of nanoinformatics. This article outlines the NDCI project and lays the foundation for a series of papers on nanomaterial data curation. The NDCI purpose is to: 1) present and evaluate the current state of nanomaterial data curation across the field on multiple specific data curation topics, 2) propose ways to leverage and advance progress for both individual efforts and the nanomaterial data community as a whole, and 3) provide opportunities for similar publication series on the details of the interactive needs and workflows of data customers, data creators, and data analysts. Initial responses from stakeholder liaisons throughout the nanoinformatics community reveal a shared view that it will be critical to focus on integration of datasets with specific orientation toward the purposes for which the individual resources were created, as well as the purpose for integrating multiple resources. Early acknowledgement and undertaking of complex topics such as uncertainty, reproducibility, and interoperability is proposed as an important path to addressing key challenges within the nanomaterial community, such as reducing collateral negative impacts and decreasing the time from development to market for this new class of technologies.
Kurds in Syria
Authors: Murad Michael
Published: August 2015

The paper focuses on Syrian Kurds, who compared to Kurds in Iraq and Turkey were out of the spotlight of academic community of researchers. Introduced are Syrian Kurds and their relationship to various regimes that ruled Syria. Complicated relation of Kurds in Syria towards consequences of the Arab Spring is also explained. Relations to the Arab Spring are affected by the historical experience. Kurdish traditional political parties were careful to join the Syrian opposition, but young activists and the diaspora (also diaspora in the Czech Republic) was less hesitant to join the opposition movement. Fight with the so called Islamic State has united Kurds in Syria, (and the same happened in Iraq as well) however some differences among them remain.
THE NEW POLISH SECURITY STRATEGY
Authors: Kutěj Libor
Published: August 2015

The new Polish National Security Strategy was approved at the end of the last year. Its creation reflected ongoing shifts in global security environment most importantly the Ukrainian crisis and current assertive behaviour of the Russian federation towards her traditional areas of geostrategic interest. It focuses on a transmission of strategic priorities from participation in international operations to an imminent provision of the Polish territorial defence. New priorities are laid upon national defence potential, fulfilment of commitments towards the NATO and strategic partnership with the United States.
NEW QUALITY OF DEFENCE COOPERATION WITHIN THE VISEGRÁD GROUP IN 2010-2014
Authors: GAWRON - TABOR Karolina
Published: August 2015

The aim of the article is to analyse the actions taken by the Visegrád Group (V4) in 2010-2014 in the field of defence and the attempt to answer the question: To what extent do the decisions taken by the Visegrád Group represent a new quality in the cooperation? In the analysed period, the Visegrád Group presented the change in the approach to the defence cooperation. The evidence for this is: placing defence cooperation on the Visegrád agenda, presenting common positions on this issue in the international arena, involving into the discussion on the defence matters other countries in the Visegrád Group Plus (V4+) formula, and, above all, setting specific objectives to implement and create the institutional structures and procedures in the defence planning. The change in the approach is also indicated by the establishment of the Visegrád EU Battlegroup (V4 EU BG). The action taken indicates the new approach, but also, to some extent, creates a new quality of the cooperation. The new quality will mean effectively completed projects and a common position consistently presented on the issues that are the most important for the region and particular countries.
Markets, money and maggots
Authors: Drew D.J.W. , Pieterse E.
Published: August 2015

This opinion paper focuses on the AgriProtein experience of the mass rearing of insects for feed with specific reference to the development of a mass rearing facility aimed at the use of organic waste for the rearing of larvae destined for the animal feed industry. The paper discusses the market related issues of producing such a product as well as consumer acceptance, finances, scale and the future prospects for such mass rearing systems. Proving the business necessitates proving the market and product; this paper summarises poultry studies done with the protein source MagMeal™, and shows that the larvae and pre-pupae of dipteran species are a viable protein source and that the use of such protein has no negative effect and often a positive effect on production parameters or carcass characteristics of broiler chickens and that no anti-nutritional or toxic effects were noted for any of the larvae and pre-pupae meals tested.
Idea de la Justicia a través de la iconografía de las Biblias medievales de Bolonia (Siglos XIII-XIV) localizadas en España
Authors: Martínez Murillo Mª. Concepción
Published: August 2015

Análisis de la representación iconográfica de la virtud de la Justicia en el Libro de la Sabiduría de las Biblias de Bolonia (siglos XIII y XIV) localizadas en España. La interpretación iconográfica se completa con el contexto histórico y la influencia de la disciplina del Derecho en Europa y, en especial, en Bolonia.
Un intento de diálogo en la Granada nazarí: El arte para ligeramente saber la lengua aráviga de Pedro de Alcalá
Authors: Folgado García Jesús R.
Published: August 2015

La obra del monje jerónimo Pedro de Alcalá, Arte para ligeramente saber la lengua aráviga (1505), constituye un hito en el intento de diálogo entre el mundo cristiano y el mundo musulmán. Escrita tras la caída del Reino de Granada en el año 1492, recoge los primeros textos impresos en árabe nazarí y tiene como finalidad llevar a la población musulmana a abrazar la fe católica. Inculturación de la fe, celebración litúrgica y respeto a la libertad personal serán el programa evangelizador que nos presente la obra.
Jurisdicción episcopal y violencia en el clero diocesano burgalés durante el siglo XV
Authors: Díaz Ibáñez Jorge
Published: August 2015

En este trabajo se realiza un análisis selectivo de las diferentes formas de presencia de la violencia en el clero diocesano burgalés durante el siglo XV. Violencia de los clérigos hacia los laicos, entre los propios clérigos y de los laicos contra los clérigos, situaciones todas ellas que fueron denunciadas ante la justicia episcopal burgalesa. Las manifestaciones de violencia fueron desde simples golpes, bofetadas y pedradas hasta ataques con cuchillos y espadas, no faltando algún caso de homicidio, todo lo cual, en definitiva, viene a ser una clara muestra de las fuertes tensiones sociales, tanto internas como externas, que a nivel local afectaban al clero rural en la diócesis de Burgos.
Numerical Analysis of Laminated Veneer Lumber Panels in Fire
Authors: Thi Van Diem , Khelifa Mourad , El Ganaoui Mohammed , Rogaume Yann
Published: August 2015

This paper presents models for calculating the fire behavior of Laminated Veneer Lumber (LVL) elements. A 2D FE thermal model was employed to analyze heat transfer within LVL panels. The thermal model was found to provide good predictions when comparing the calculated temperatures and residual cross-section dimensions of LVL panels with the experiment results.
Cohesive Zone Damage-Healing Model for Self-Healing Materials
Authors: Abu Al-Rub Rashid K. , Alsheghri Ammar
Published: August 2015

A cohesive zone damage-healing model (CZDHM) derived based on the laws of thermodynamics for self-healing materials is presented. The well-known nominal, healing, and effective configurations of classical continuum damage mechanics are extended to self-healing materials. A new physically-based internal crack healing state variable is proposed for describing the healing evolution within the crack cohesive zone. The effects of temperature, crack-closure, and resting time on the healing behavior are discussed. Numerical examples are conducted to show the various novel features of the formulated CZDHM.
Constitutive Model for Timber Fracture under Tensile and Shear Loads
Authors: Smidova Eliska , Kabele Petr
Published: August 2015

A 2D homogeneous orthotropic constitutive model of tensile and shear fracture in timber based on fixed smeared crack approach has been developed and implemented in ATENA®finite element software. The model captures (1) elastic and inelastic behavior in small deformations range, (2) material orthotropy, both in linear and non-linear range, (3) cracking across or along fibers, and (4) behavior under unloading/reloading. In this contribution we present model validation through numerical simulations of compact tension shear (CTS) tests of Radiata Pine timber.
Damage Accumulation and Fracture of Weld Joints under Low-Cyclic Loading Conditions
Authors: Kornev V.M.
Published: August 2015

Failure of weld joints under single and cyclic pulsating loading conditions is under consideration. A weld joint is modeled by three-layer composite. Stepwise propagation of the internal I mode crack under cyclic loading is investigated. Delamination of bimaterial composed of two structured materials is considered when a crack is located at the interface between two media. Loads under pulsating loading conditions are studied for elastic-plastic material. For analysis of this process, diagrams of quasi-brittle fracture of solids under cyclic loading conditions are proposed to be used. One of curves of the proposed diagram bears resemblance to the Kitagawa-Takahashi diagram. Estimates of average dimensionless velocity of stepwise crack propagation per loading cycle have been obtained in an explicit form for plain specimens of finite width. The relations derived for the average crack growth rate can be considered as structural expressions for plotting Paris’ curves.
A Micro-Cell Size Dependent Damage Law of Concrete
Authors: Liang Shi Xue , Ren Xiao Dan , Li Jie
Published: August 2015

A micro-cell size dependent damage law is proposed by the multi-scale damage representation to remedy the mesh sensitivities involving in the numerical simulations. The homogenization based multi-scale damage representation is firstly introduced in obtaining the macro-damage evolution from micro-cell analysis. Then, the micro-cells with different sizes are generated and the corresponding simulations are given. Based on the simulation results, we define the micro-cell size dependent damage law. Finally, the accuracy and efficiency of the proposed damage law are verified by the notched beam simulation results.
Mathematical and Numerical Modelling of Large Axisymmetric Creep Strains and Damage
Authors: Szuwalski Krzysztof , Ustrzycka Aneta
Published: August 2015

The paper presents a simulation model for the creep process of rotating disks under radial tensional pressure subjected to of body force. The finite strain theory is applied. The material is described by the Norton-Bailey law generalized for true stresses and logarithmic strains. The mathematical model is formulated in form of set of four partial differential equations with respect to radial coordinate and time. Necessary initial and boundary conditions are also given. To make the model complete, the numerical procedure for solving this set is proposed. What is worth noticing the classical FEM is not applicable, because not only geometry, but also loading (body forces) change in time during the creep process. It would demand redefinition of finite elements at each time step. In uniaxial problem similar model was presented in [4], but now it is developed for complex stress state. Possible different formulations of initial and boundary conditions may be found in [5]. The procedure may be useful in problems of optimal design of full disks in [6].
Coupled Damage-Plasticity Modelling of Ductile Failure in an Aluminium Alloy
Authors: Nguyen Giang Dinh , Korsunsky Alexander M. , Belnoue Jonathan
Published: August 2015

The ductile failure of metallic alloys is characterized by the long plateau of the stress-strain response during plastic deformation. In aluminium alloys this complex process is principally mediated by crystal slip associated with dislocation nucleation, motion, interaction, and locking. This results in hardening, i.e. the increase in the flow stress and progressive exhaustion of ductility, eventually leading to damage. Therefore, in the advanced stages of deformation the strength increase at the material level competes with overall stiffness and strength decrease due to effective cross-section reduction by decohesion and voiding. Capturing the complex hierarchical failure of these materials requires developing sophisticated concurrent constitutive descriptions of both plastic deformation and damage at different stages of failure. In the present study the modelling of aluminium alloy failure is accomplished using a plasticity-based model with nonlinear hardening coupled with isotropic damage in a thermodynamically consistent framework. The model developed in this way is enhanced with nonlocal regularization to deal with material instabilities issues due to softening. Emphasis is placed on the correspondence between experimental measurements of the essential work of fracture and the non-essential work of fracture, and both local and spatial sets of model parameters. This approach is the key to assuring a constitutive response consistent with experimental observations, an issue usually overlooked in nonlocal constitutive modelling. Numerical examples are used to demonstrate the features of the new approach.
Complex Damage Variables in Continuum Damage Mechanics
Authors: Voyiadjis George Z. , Kattan Peter I.
Published: August 2015

The concept of complex damage variables is introduced in this work. These damage variables have both real and imaginary parts. They are introduced not to use them in practical applications but to try to derive a direct relationship between the damage due to cross-sectional area reduction and the damage due to elastic stiffness degradation. In addition this concept can provide an insight in addressing the concept of healing that the authors have extensively published as well as the concept of undamageable materials. Toward this goal some success is achieved in the sense that some complicated relationships between the two damage processes are formulated. These relationships and the complex variable approach are novel ideas in Continuum Damage Mechanics. Throughout the formulation the hypothesis of strain equivalence is used in order to simplify the mathematical equations. This work can be extended and generalized by substituting the hypothesis of energy equivalence but this will complicate the equations unnecessarily.
Parameter Identification of a Damage Model for the Lifetime Prediction of Adhesively Bonded Joints
Authors: Kroll Ulrich , Matzenmiller Anton
Published: August 2015

A damage model for thin adhesively bonded joints is presented, which predicts the time to creep-fatigue failure of the joint subjected to combined static and cyclic sustained loadings with constant or variable amplitudes. The influences of particular model parameters on the predicted lifetime are elaborated suggesting the proposed stepwise parameter identification strategy by means of creep and Wöhler fatigue tests until rupture. The parameters are identified and computationally optimized. As a conclusion, the model prediction is verified and validated.
From Damage to Fracture, a Modelization Based on Moving Discontinuities and Layers
Authors: Stolz Claude
Published: August 2015

A damage modelization is proposed based on a continuous transition from undamaged to damaged material. The evolution of damage is associated with a moving layer of finite thickness $l_c$, then initiation and propagation of damage can be unified in the same constitutive law. The driving force associated to the layer motion is a generalized release rate of energy. Using a normality rule based on this force the solution of the rate boundary value problem of propagation and displacement satisfies a variational inequation. Applications of the model are proposed.
Fast Plastic Integration Algorithm for Damage Prediction in Forming Process Simulations
Authors: Halouani Ali , Li Yu Ming , Abbès Boussad , Guo Ying Qiao
Published: August 2015

The iterative Return Mapping Algorithm (RMA) is widely used for the plastic integration owing to its accuracy and efficiency, but it is CPU time consuming and may cause divergence problems in case of large strain increments. This paper presents a fast plastic integration method called Direct Scalar Algorithm (DSA) for the damage prediction in forming process simulations. A simplified three-dimensional (3D) strain-based damage model is coupled with the plasticity and implemented into the DSA which does not need iterative solution to make the plastic integration very fast and robust even for very large strain increments. The basic idea is to transform the constitutive equations in terms of the unknown stress vectors into a scalar equation in terms of the equivalent stresses which can be determined by using the experimental tensile curve; thus, the plastic multiplier ∆λ can be directly calculated. The DSA is as accurate as RMA but much faster for the plastic integration.
Modelling of Chip Breakage in Machining Process with Damage Mechanics Model
Authors: Wu Bo , Yan Yu Lin , Münstermann Sebastian
Published: August 2015

Controlled chip breakage is important for machining process. In order to investigate the chip breakage behaviour in turning process, damage mechanics approach is applied in FE simulation of chip breakage. In this work, an advanced damage mechanics model is implemented for description of the plastic flow and damage behaviour of chip material in simulation. This material model takes the temperature, strain rate as well as state of stress into consideration, which are essential for application in machining processes.
Validation of Micro-Meso Electrical Relations for Laminates with Varying Anisotropy
Authors: Selvakumaran Lakshmi , Lubineau Gilles
Published: August 2015

For electrical impedance tomography (EIT) to be useful in monitoring transverse cracks in composites, it is imperative to establish the relation between conductivity and cracking density. Micro to meso scale homogenization has been developed for classical carbon fiber reinforced polymer (CFRP) laminate which provides such a relationship. However, we have shown in previous studies that the detectability of transverse cracks in such CFRP, which are characterized by very anisotropic electrical properties, is poor. Then, it is better to lower the electrical anisotropy, which can be achieved by various technologies including doping the polymeric resin by conductive nanoparticles. However, the validity of mesoscale homogenization for laminates with such low anisotropy has not been tested before. Here, we show that the mesoscale damage indicator is intrinsic for composites with varying anisotropy.
Probabilistic Weibull Methodology for Fracture Prediction of Brittle and Ductile Materials
Authors: Muñiz-Calvente Miguel , Fernández Canteli Alfonso , Shlyannikov Valery , Castillo Enrique
Published: August 2015

In this work, a three-parameter Weibull methodology for fracture prediction of brittle and ductile materials is presented. The approach proposed requires previous definition of the failure criterion to be applied. The parameter estimation is achieved for proportionally and non-proportionally increasing stresses. The case of two concurrent failure types is also handled. The resulting primary failure distribution can be expressed as a function of an effective size (length, area or volume) for its subsequent application in practical design of specimens or components using FEM.
Application of a Local Continuum Damage Model to Porous TRIP-Steel
Authors: Seupel Andreas , Kuna Meinhard
Published: August 2015

Aim of this study is to describe the ductile damage of metastable austenitic steels which show TRansformation Induced Plasticity (TRIP). Therefore, a criterion for the austenite to martensite transformation, the caused additional hardening and evolution equations for the TRIP-strain are incorporated into the damage model of Rousselier. As a first approach, the model is calibrated against unit cell simulations of the porous material for different stress triaxialities.
Effect of Freeze-Thaw Cycles on Mechanical Behaviors of Ceramsite Concrete under Impact Loading
Authors: Chen Jiang Ying , Qiu Xin , Shi Guan Yin , Chen Bo Fei , Huang Xu Sheng
Published: August 2015

In order to study the influence of freezing and thawing on the dynamic behavior of ceramsite concrete, specimens with four kinds of ceramsite volume fraction including 0%, 15%, 30% and 45% which subjected to 0, 10, 20, 30 and 40 cycles of freezing and thawing respectively, are tested by means of the Spilt Hopkinson Pressure Bar technique. The experimental results showed that under dynamic loading the ceramisite concrete was weakened with increasing of the number of freeze-thaw cycles. Changes of dynamic compressive strength and damage evolution affected by freeze-thaw cycling and volume fraction of ceramsite are discussed in the paper.
Damage Theory Based Fatigue Simulation of Concrete Structure
Authors: Liang Jun Song , Li Jie
Published: August 2015

The fatigue problem of concrete has long been studied through many different methods. However, the fatigue process and failure patterns of concrete structures have never been well simulated due to the lack of comprehensive understanding of the material properties under fatigue loads. In order to carry out an accurate simulation of the fatigue behavior of concrete structures, this paper proposes a new damage theory based fatigue constitutive model for concrete. The present model adopts two damage variables to describe the degradation of macro mechanical properties of concrete under tension and compression, respectively. And the tensile and compressive damage evolutions are related to the corresponding effective stress spaces. Specifically, by implementing the present model into the nonlinear finite element package, the bending fatigue process of a concrete beam is simulated. Meanwhile a set of numerical tests are presented, through which the validity and effectiveness of the proposed model for the simulation of concrete structures are illustrated.
Preparation and Characterization of Clays from Different Areas in Ban Bo Suak, Nan Province, Thailand
Authors: Malee Usanee , Thiansem Sakdiphon
Published: August 2015

The scientific process was used to explain characterization and physical properties of the clay sample close to the ancient Nan kiln site. These samples were obtained from JQA, FQB, PQC and NQD. X-ray diffraction (XRD) and X-ray fluorescence (XRF) technique were used to determine the chemical composition and phase transformation before and after fired at 800-1250 °C. XRF result was confirmed that all clay samples mainly contained SiO2(>80 wt. %) XRD pattern indicated that quartz was the majority of phase in the all of them. High amount of Fe2O3(>1.6 wt. %) was related to the red-brown tone color. The clay sample could be fired up to 1280 °C without wrapping behavior; it was found that FQB clay had the highest firing resistance due to the maximum quartz content.
Properties of Steel Fiber Reinforced Geopolymer
Authors: Wongruk Rachamongkon , Songpiriyakij Smith , Sukontasukkul Piti , Chindaprasirt Prinya
Published: August 2015

In this study, the mechanical properties of steel fibre reinforced geopolymer (SFRG) are investigated. The geopolymer is consisted of fly ash, silica fume and activator solution, sodium silicate and sodium hydroxide. Five mix proportions of fly ash and silica fume are varied to study the effect of fly ash/silica fume ratios (FA/SF). This experimental series focus mainly on flexural strength and flexural toughness performance of SFRG. Hooked-ends steel fibers are used at 0.5% and 1% by volume fractions. The experiment is carried out based on ASTM C1609 (beam specimens) for flexural performance. The results showed that fibre can significantly enhance the both flexural strength and toughness of geopolymer. The enhancement also increases with the increasing fibre volume fraction.
The Effects of Solvents on the Solvothermal Synthesis of BiVO4 Photocatalyst Powders
Authors: Thanomsri N. , Mongkolkachit C. , Sato T. , Wu X. , Sujaridworakun Pornapa
Published: August 2015

In this study, the effects of different solvents such as ethanol, ethylene glycol, glycerol on the preparation of BiVO4 via solvothermal process, and the influent of calcination heat treatment were studied. The crystal structure, surface area, morphology and optical properties of the obtained BiVO4 particles were investigated by means of X-ray Diffraction (XRD), Brunauer Emmett Teller method (BET), Scanning electron microscope (SEM) and UV-Vis reflectance spectroscopy (UV-Vis DRS), respectively. XRD patterns reveal that all of the obtained BiVO4 samples prepared by solvothermal at 130°C for 4 h have monoclinic structure. The UV-Vis DRS demonstrates that the band gaps of prepared BiVO4 are about 2.38-2.40 eV. The photocatalytic activity was evaluated by photo-degradation of rhodamine B (Rh B) solution under visible light irradiation (λ>420 nm). As the results, the BiVO4 prepared by using ethanol having high crystallinity and surface area showed the highest visible light photocatalytic activity compared to using glycerol and ethylene glycerol, respectively. Furthermore, the photocatalytic activity of BiVO4 prepared by using ethylene glycerol and glycerol could be enhanced by calcination heat treatment at 500°C for 2 h.