bluuebunny/crossref_metadata_2025 huggingface dataset:
‘Certainly theMuslimis the very devil incarnation’: Islamophobia andThe Merchant of Venice
Authors: Awan Imran , Issa Islam
Published: September 2018

In this paper, we examine Shakespeare's sixteenth‐century play,The Merchant of Venice. Anti‐Semitism is a key theme in this play. The well‐known central character, Shylock, is a Jewish man ridiculed and victimised because of his identity. Much literary research has been done on the anti‐Semitism of the play, and many social studies have compared anti‐Semitism and Islamophobia, but scarcely any research brings a Shakespearean play from the sixteenth century into the context of twenty‐first century Islamophobia. There are a number of similarities between the manner in which Shylock is ostracised and the current victimisation that Muslim communities are facing in Europe and more specifically the UK. With this in mind, we explore contextual and thematic elements of this play and argue that it is possible to apply the way Shylock is unfairly victimised on stage because of his identity as a Jew to the treatment of some Muslims today. In particular, the treatment he faces shares stark similarities with the types, impacts and consequences of Islamophobic hate crime today.
HDAC2 dysregulation in the nucleus basalis of Meynert during the progression of Alzheimer's disease
Authors: Mahady L. , Nadeem M. , Malek‐Ahmadi M. , Chen K. , Perez S. E. , Mufson E. J.
Published: September 2018

Aims

Alzheimer's disease (AD) is characterized by degeneration of cholinergic basal forebrain (CBF) neurons in the nucleus basalis of Meynert (nbM), which provides the major cholinergic input to the cortical mantle and is related to cognitive decline in patients with AD. Cortical histone deacetylase (HDAC) dysregulation has been associated with neuronal degeneration during AD progression. However, whether HDAC alterations play a role in CBF degeneration during AD onset is unknown. We investigated global HDAC protein levels and nuclear HDAC2 immunoreactivity in tissue containing the nbM, changes and their association with neurofibrillary tangles (NFTs) during the progression of AD.

Methods

We used semi‐quantitative western blotting and immunohistochemistry to evaluate HDAC and sirtuin (SIRT) levels in individuals that died with a premortem clinical diagnosis of no cognitive impairment (NCI), mild cognitive impairment (MCI), mild/moderate AD (mAD) or severe AD (sAD). Quantitative immunohistochemistry was used to identify HDAC2 protein levels in individual cholinergic nbM nuclei and their colocalization with the early phosphorylated tau marker AT8, the late‐stage apoptotic tau marker TauC3 and Thioflavin‐S, a marker of β‐pleated sheet structures in NFTs.

Results

In AD patients, HDAC2 protein levels were dysregulated in the basal forebrain region containing cholinergic neurons of the nbM. HDAC2 nuclear immunoreactivity was reduced in individual cholinergic nbM neurons across disease stages. HDAC2 nuclear reactivity correlated with multiple cognitive domains and with NFT formation.

Conclusions

These findings suggest that HDAC2 dysregulation contributes to cholinergic nbM neuronal dysfunction, NFT pathology, and cognitive decline during clinical progression of AD.
Comparing Arabidopsis receptor kinase and receptor protein‐mediated immune signaling reveals BIK1‐dependent differences
Authors: Wan Wei‐Lin , Zhang Lisha , Pruitt Rory , Zaidem Maricris , Brugman Rik , Ma Xiyu , Krol Elzbieta , Perraki Artemis , Kilian Joachim , Grossmann Guido , Stahl Mark , Shan Libo , Zipfel Cyril , van Kan Jan A. L. , Hedrich Rainer , Weigel Detlef , Gust Andrea A. , Nürnberger Thorsten
Published: September 2018

Pattern recognition receptors (PRRs) sense microbial patterns and activate innate immunity against attempted microbial invasions. The leucine‐rich repeat receptor kinases (LRR‐RK) FLS2 and EFR, and the LRR receptor protein (LRR‐RP) receptors RLP23 and RLP42, respectively, represent prototypical members of these two prominent and closely related PRR families.

We conducted a survey of Arabidopsis thaliana immune signaling mediated by these receptors to address the question of commonalities and differences between LRR‐RK and LRR‐RP signaling.

Quantitative differences in timing and amplitude were observed for several early immune responses, with RP‐mediated responses typically being slower and more prolonged than those mediated by RKs. Activation of RLP23, but not FLS2, induced the production of camalexin. Transcriptomic analysis revealed that RLP23‐regulated genes represent only a fraction of those genes differentially expressed upon FLS2 activation. Several positive and negative regulators of FLS2‐signaling play similar roles in RLP23 signaling. Intriguingly, the cytoplasmic receptor kinase BIK1, a positive regulator of RK signaling, acts as a negative regulator of RP‐type immune receptors in a manner dependent on BIK1 kinase activity.

Our study unveiled unexpected differences in two closely related receptor systems and reports a new negative role of BIK1 in plant immunity.
Weight loss associated with sodium‐glucose cotransporter‐2 inhibition: a review of evidence and underlying mechanisms
Authors: Lee P. C. , Ganguly S. , Goh S.‐Y.
Published: September 2018

With their novel, insulin‐independent mechanism, sodium‐glucose cotransporter‐2 (SGLT2) inhibitors are a major turning point in the management of type 2 diabetes mellitus. At present, there are several SGLT2 inhibitors available or in development, and these oral anti‐hyperglycaemic agents lower plasma glucose through the inhibition of SGLT2‐mediated reuptake of filtered glucose in the kidney. This unique mechanism of action is also expected to result in other beneficial effects, such as weight loss and blood pressure reduction. In various studies, including randomized controlled trials and real‐world studies, patients treated with SGLT2 inhibitors have reported weight loss of around 1 to 3 kg. This review describes the characteristics of weight loss associated with SGLT2 inhibitor therapy, the clinical factors affecting SGLT2 inhibitor‐associated weight loss and the possible underlying mechanisms of SGLT2 inhibitor‐associated weight loss, including changes in metabolism and body composition, and the role of a reduction in insulin dose and compensatory hyperphagia. Understanding the weight loss effect of SGLT2 inhibitors, its related factors and underlying mechanisms can aid clinicians in optimal treatment decision‐making, provide valuable insight on both obesity and diabetes management and reveal areas of future research and new therapeutic options.
The challenges that spatial context present for synthesizing community ecology across scales
Authors: Patrick Christopher J. , Yuan Lester L.
Published: September 2018

Accurately characterizing spatial patterns on landscapes is necessary to understand the processes that generate biodiversity, a problem that has applications in ecological theory, conservation planning, ecosystem restoration, and ecosystem management. However, the measurement of biodiversity patterns and the ecological and evolutionary processes that underlie those patterns is highly dependent on the study unit size, boundary placement, and number of observations. These issues, together known as the modifiable areal unit problem, are well known in geography. These factors limit the degree to which results from different metacommunity and macro‐ecological studies can be compared to draw new inferences, and yet these types of comparisons are widespread in community ecology. Using aquatic community datasets, we demonstrate that spatial context drives analytical results when landscapes are sub‐divided. Next, we present a framework for using resampling and neighborhood smoothing to standardize datasets to allow for inferential comparisons. We then provide examples for how addressing these issues enhances our ability to understand the processes shaping ecological communities at landscape scales and allows for informative meta‐analytical synthesis. We conclude by calling for greater recognition of issues derived from the modifiable areal unit problem in community ecology, discuss implications of the problem for interpreting the existing literature, and identify tools and approaches for future research.
Choosing the anesthetic and sedative drugs for supraventricular tachycardia ablations: A focused review
Authors: Vladinov Greta , Fermin Lilibeth , Longini Renee , Ramos Yanett , Maratea Edward
Published: September 2018

This study provides a review of the contemporary literature for the effects of most commonly used anesthetic drugs for sedation and anesthesia during adult electrophysiologic (EP) studies where supraventricular tachycardias (SVT) need to be induced for diagnostic purposes and/or catheter ablation. Some medications may affect cardiac electrophysiology and conduction, altering the ability to induce the arrhythmia, and may have negative impact on mapping and ablation treatment. The objective of the study is to determine the best sedative choice during SVT ablations. The authors searched MEDLINE, PubMed, and Google Scholar databases for published articles within the past 20 years (1998‐2018) that have evaluated the effects of common anesthetic drugs during SVT ablations. Further articles were identified through crossreferencing, discussion with electrophysiologists, and hand‐searching key electrophysiology and anesthesia journals. Eight review articles, two randomized control trials, six prospective observational studies, one retrospective observational study, and two case reports were included in this review. Seven of the studies focused on the pediatric population. The findings about the effects of the commonly used anesthetics are discussed further in detail. Sevoflurane had no clinically important effects on sinoatrial (SA) node activity, or the normal atrioventricular (AV), or accessory pathway. Midazolam and fentanyl, alone or in combination, neither alter the inducibility of reentrant tachycardia nor have they shown to affect the SA node, refractory periods of AV conduction, or accessory pathways. Similar findings were reported by investigators with propofol, except for ectopic atrial tachycardia in children, which remained un‐inducible in one of the studies. Remifentanil and dexmedetomidine lengthened both sinus cycle and AV conduction. Dexmedetomidine increased the atrial refractory period and diminished atrial excitability. Ketamine shortened atrial conduction and successfully returned prolongation of sinus node conduction due to dexmedetomidine. In conclusion, the current literature regarding sedation for SVT studies in the adult population is sparse. Midazolam, propofol, fentanyl, and remifentanil can be used safely in patients undergoing EP studies without significant interference with electrophysiological variables or the inducibility of reentrant tachycardias in usual clinical doses. Low‐dose ketamine has potential use as an adjunctive medication in the EP lab and additional studies would be beneficial. The effects of dexmedetomidine on conduction and arrhythmia inducibility during SVT ablation is not as clear as studies have yielded conflicting results, and may not be the best choice for sedation in this patient population.
Perceptual Kinds as Supervening Sortals
Authors: Skrzypulec Błażej
Published: September 2018

It seems intuitive that in situations of perceptual recognition, additional properties are represented. While much has been written about the significance of such properties for perceptual phenomenology, it is still unclear (a) what the relation between recognition‐based properties and lower‐level perceptual properties is and (b) whether it is justified to classify them as kind properties. Relying on results in cognitive psychology, I argue that recognition‐based properties (I) are irreducible, high‐level properties, and (II) are kind properties by virtue of being sortal properties but (III) supervene on lower‐level properties and so are unlikely to be natural kind properties.
Identification of simple‐sequence‐repeat markers linked to Fusarium wilt (Fusarium oxysporum f.sp. carthami) resistance and marker‐assisted selection for wilt resistance in safflower (Carthamus tinctorius L.) interspecific offsprings
Authors: Anjani Kammili , Ponukumatla Bhavna , Mishra Debadutta , Ravulapalli Durga Prasad
Published: September 2018

Safflower (Carthamus tinctorius L.) is a multipurpose oilseed crop. Fusarium wilt (Fusarium oxysporum f.sp. carthami) is the major damaging disease in safflower. In the present investigation, Fusarium wilt resistance was introgressed from two wild species, Carthamus oxyacantha and Carthamus palaestinus, into susceptible cultivated species through interspecific hybridization. Inheritance of wilt resistance indicated single dominant gene control. Eight simple‐sequence‐repeat (SSR) markers each in (‘Nira’ × C. oxyacantha) and (‘Nira’ × C. palaestinus) were found to be linked to wilt resistance. Marker‐assisted selection for wilt resistance was performed using these markers in F3–F7 generations of both crosses. Six wilt resistant interspecific lines evaluated for 2 years under nondisease conditions have recorded 9%–29% higher seed yield than the high yielding cultivar, ‘A1’. The wilt resistant lines would serve as new sources of resistance to wilt in safflower. The SSR markers linked to wilt resistance would be useful for precise selection of wilt resistance at seedling stage in large segregating populations without attempting screening in artificially inoculated conditions and pyramiding of wilt resistant genes from wild into a common background.
Pooled mapping of quantitative trait loci conferring male sterility‐conditioned glume split in rice (Oryza sativa)
Authors: Omboki Ratemo Billy , Zheng Yan , Chen Zhiwei , Guan Huazhong , Tang Weiqi , Huang Likun , Xie Xiaofang , Wu Weiren
Published: September 2018

Glume split (GS) refers to the phenomenon that the lemma and palea of a rice seed cannot be fully closed. There is a kind of GS that occurs only under male sterility. Such male sterility‐conditioned GS (mscGS) can severely reduce the quality of hybrid rice seeds and therefore is a serious problem in hybrid rice production. To reveal the genetic basis of mscGS, we employed the method of bulked segregant analysis combined with deep sequencing to map quantitative trait loci (QTLs) conferring mscGS. By analysing a pair of opposite DNA pools made up of 50 extreme individuals each from an F2 population of 509 individuals, we mapped two major QTLs on the long arm terminals of chromosomes 5 and 6, respectively. We named them qmscGS5 and qmscGS6. The two QTLs both function mainly in additive mode, explaining a heritability of 16.98% and 11.96% by their additive effects, respectively. The information obtained in this study will facilitate marker‐assisted breeding of low‐GS male‐sterile lines and positional cloning of genes controlling mscGS in rice.
Comparison of UV protection properties of cotton fabrics treated with aqueous and methanolic extracts of Solanum nigrum and Amaranthus viridis plants
Authors: Saleem Muhammad Asad , Nazir Ahsan , Nazir Faiza , Ayaz Pirah , Faizan Muhammad Qasim , Usman Muhammad , Hussain Tanveer
Published: September 2018

Harmful effects of ultraviolet rays and protection against them have been long discussed. Numerous synthetic dyes, finishes, UV absorbers, and optical brightening agents are present in the market for decades for achieving UV protection through textiles. However, due to environmental impacts of these chemical agents, textile industry is looking for alternatives. In this regard, some natural dyes and plant extracts have shown promising results. However, use of colorless plant extracts as UV protective finishes is still rare. In this study, ultraviolet protection factor (UPF) rating of bleached cotton fabric has been improved by the application of plant extracts with minimal change in fabric's color. For this purpose, two medicinal plants, that is, Solanum nigrum and Amaranthus viridis were selected and bleached cotton fabric was treated with their methanolic and aqueous extracts. Fabrics treated with both extracts exhibited excellent UPF ratings.
A Norm of Evidence and Research in Decision‐making (NERD): Scale Development, Reliability, and Validity
Authors: Hall Jeremy L. , Van Ryzin Gregg G.
Published: September 2018

Evidence‐based management is on the rise as a strategy to promote more rational decision‐making and effectiveness in governance and public service delivery. To understand how widespread the use of evidence is among managers in various settings, and why evidence is emphasized more in some settings than others, it is necessary to have a good measure of the use of research and evidence in management decision‐making. This article reports on the development and testing of a new multi‐item scale, Norm of Evidence and Research in Decision‐making (NERD), that can be used across organizational and functional settings to assess evidence‐based management practices within an agency. The results indicate that the scale is internally consistent (reliable) and that it correlates with criteria of the underlying construct (valid). The article concludes with a discussion of the potential utility of the scale for advancing research and understanding about the use of evidence by public and nonprofit managers.
Oxythiamine improves antifungal activity of ketoconazole evaluated in canine Malassezia pachydermatis strains
Authors: Siemieniuk Magdalena , Sosnowska Katarzyna , Czerniecki Jan , Czyzewska Urszula , Winnicka Katarzyna , Tylicki Adam
Published: September 2018

Background

Malassezia pachydermatis is an opportunistic yeast involved in skin and ear canal infections of dogs and cats. Reports suggest that strains of M. pachydermatis resistant to commonly used antifungal agents may be emerging. Therefore, new therapeutic strategies should be explored.

Objectives

The synergistic effect of oxythiamine (OT) and ketoconazole (KTC) was analysed using a reference strain and field isolates (n = 66) of M. pachydermatis. Hydrogel formulations containing these components also were evaluated.

Methods and materials

The minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of OT, KTC and their mixtures were determined by a broth macrodilution method. The antifungal effects of hydrogel formulations were determined by a plate diffusion method.

Results

The MIC and MFC values of OT were in the range 0.08 × 103 to 10 × 103 mg/L. All M. pachydermatis strains showed higher susceptibility to KTC (MICs and MFCs in the range 0.04–0.32 mg/L). Formulations that combined OT and KTC showed a synergistic effect for all tested isolates (n = 66). Hydrogels that contained OT at a concentration of 10 × 103 or 20 × 103 mg/L and KTC at the concentration of 0.1 × 103 mg/L showed a stronger effect than a commercially available product with KTC alone (20 × 103 mg/L).

Conclusions and clinical importance

Synergy of these drugs may allow for successful topical treatment which utilizes lower doses of KTC without changing its therapeutic effectiveness. Hydrogel formulations proved to be attractive drug carriers for potential topical use.
An Analysis of Enhanced Faculty Engagement on Student Success and Satisfaction in an Online Classroom
Authors: Bao Mingzhen , Selhorst Adam L. , Moore Teresa Taylor , Dilworth Andrea
Published: September 2018

Difficulty building meaningful student and instructor relationships can create a challenge for online instructors. A Faculty of Practice (FoP) role was created in a large online university requiring greater faculty engagement to bolster student achievement. This study examined the impact of the FoP role on student success and satisfaction over a 6-month period. The position emphasized an increased engagement through enhanced personalized learning, subject-matter expertise, discipline mentoring, and community building. The increased engagement was promoted through requirements mandating a consistent presence in the classroom, personalized email interactions with students prior to course start, promotion and instruction of material through individual conferences, outreach to students with late or missing assignments, and weekly office hours including video conference options. None of these requirements are mandated for Associate Faculty (AF) teaching the courses. Data on student success included an analysis of student GPA, pass rates, completion rates, and progression to next course rates for FoP and AF courses. Student satisfaction was evaluated through the analysis of Student End-of-course Surveys (EoCS). Student data showed a significant increase in student GPA with the FoP when compared to AF courses. No differences were seen in pass, completion, or progression rates. Increase in student satisfaction for FoP courses as measured by EoCS was seen upon comparison with AF. Students noted a greater connection with the FoP and indicated stronger relationships with the FoP. Based on the analysis, we conclude the FoP role has the potential to improve student success and satisfaction in the online classroom.
Families of Children with Down Syndrome in Turkey: A Sociocultural Approach
Authors: Ordem Ozlem Aydogmus
Published: September 2018

Studies on children with Down syndrome have been on the rise in recent years because interdisciplinary and multidisciplinary approaches have been developed to understand both parents and children with Down syndrome. This study aimed to analyze the views of Turkish parents of children with Down syndrome from a critical sociocultural perspective. Five families of children with Down syndrome were interviewed. These families discussed their views composed of medical and familial discourses, legal rights, bureaucracy, sociality, socialization, outsiders’ perspectives, criticism to educational and medical system and resistance through social dialogue. The qualitative results of the study show that the families developed a different discourse that resisted the conventional discourses created by medical institutions and macro social structures. In addition, negative and pessimistic perspectives of others were, to a large extent, eliminated and transformed into more positive and optimistic viewpoints through social dialogue and constructive narratives.
Examination of Listening Anxiety of Turkish Language Teacher Candidates
Authors: Er Onur , Bozkirli Kürşad Çağrı , Polatcan Faruk
Published: September 2018

The purpose of this study is to examine the listening anxiety of Turkish language teacher candidates in terms of various variables. “Listening Anxiety Scale” developed by Maden and Durukan (2016) was used as data collection tool in the study conducted by a survey model. The Cronbach's Alpha coefficient of the scale was found to be 0.88. The data of the research was obtained from randomly selected 168 Turkish language teacher candidates studying in Atatürk University in 2017-2018 academic years. The obtained quantitative data by the application of the scale was transferred to SPSS Windows 15 package software program. As the result of the research using statistical package program for data analysis, it was found that even it has not been high, Turkish language teacher candidates have listening anxiety above the average and it was determined that listening anxiety has not differed significantly according to gender, grade, most frequently used language skill, and status of reading books regularly.
Celestial Gearbox
Authors: Efstathiou Kyriakos , Efstathiou Marianna
Published: September 2018

Like many great discoveries, the Antikythera Mechanism was found by accident. In time, however, analysis using X-ray and other advanced imaging revealed its true nature, and the Antikythera Mechanism is now considered as important for technology and sciences as the Acropolis for the architecture and arts. The object is the remains of the earliest known analog computer. Now we know that it was an extremely advanced mechanism that could be used to calculate and predict astronomical events. This article shows how researchers from the Aristotle University of Thessaloniki, Greece, used sophisticated imaging tools to gather data and create a working model to test their theories against the recreated mechanism itself.
Strong Medicine
Authors: Gibson Tom
Published: September 2018

In the United States, the highest incidence of ACL injury is to athletes, many of whom are soccer players. Surgery is often required to repair those torn ACLs, and surgeons are working with mechanical engineers to better understand the physiology of children’s knees in order to better repair the injuries–or perhaps avert them entirely. This article delves into how these engineers and biomechanics specialists are applying techniques normally reserved for hard materials like steel to soft tissue.
Machine Learning in Gas Turbines
Authors: Michelassi V. , Allegorico C. , Cioncolini S. , Graziano A. , Tognarelli L. , Sepe M.
Published: September 2018

This paper describes a selection of Baker Hughes, a GE company (BHGE) activities to support Gas Turbine (GT) design and operation from simple to more elaborate applications of Machine Learning (ML).
Evaluation of Wear Resistance of Dental Chairside CAD/CAM Glass Ceramics Reinforced by Different Crystalline Phases
Authors: Zhang Qianqian , Gao Shanshan , Liu Chunxu , Lu Yuqing , Chen Xin , Yu Haiyang
Published: September 2018

The mechanical properties of crystalline phase of glass ceramics are critical. This study aimed to evaluate wear resistance of different crystalline-reinforced dental chairside computer-aided design/computer-aided manufacturing (CAD/CAM) glass ceramics. Materials of feldspar (Vita Mark II, VM), leucite (IPS Empress CAD, EC), lithium disilicate (IPS e.max CAD, EX), lithium disilicate enriched with zirconia (Vita Suprinity, VS), and enamel were embedded, grounded, and polished, respectively. Samples were indented with a Vickers hardness tester to test the fracture resistance (KIC). Two-body wear tests were performed in a reciprocal ball-on-flat configuration under artificial saliva. The parameters of load force (50 N), reciprocating amplitude (500 μm), frequency (2 Hz), and the test cycle (10,000 cycles) were selected. Specimen microstructure, indentation morphology, and wear scars were observed by scanning electron microscope (SEM), optical microscopy, and three-dimensional profile microscopy. EX, VS, and EC demonstrated significantly higher KIC values than the enamel, while ceramic materials showed smaller wear depth results. Cracks, massive delamination, and shallow plow were seen on the enamel worn scar. Long deep plow, delamination, and brittle cracks are more common for VM and EC, and short shallow plow and smooth subsurface are the characteristics of EX and VS. Greater fracture toughness values indicated higher wear resistances of the materials for the test glass ceramics. The CAD/CAM glass ceramics performed greater wear resistance than enamel. Feldspar- and leucite-reinforced glass ceramics illustrated better wear resistance similar to enamel than lithium disilicate glass ceramics, providing amicable matching with the opposite teeth.
Anti-Galling Effects of α-Zirconium Phosphate Nanoparticles as Grease Additives
Authors: Chen Yan , Wang Xuezhen , Clearfield Abraham , Liang Hong
Published: September 2018

Grease plays important roles in reducing frictional loss and providing protection of rubbing surfaces. In this research, we investigated the effects of α-zirconium phosphate nanoparticles as additives in grease on the galling behavior of a pair of steels (4130 against P530). The results showed that the addition of 0.5 wt% of nanoparticles in petroleum jelly could reduce the friction for 10% and the area being galled for 80%. In terms of particle sizes, the 1 μm sized particles have profound influence in galling reduction. This is due to the increased contribution of van der Waals forces in the stacked layers of those particles. Under shear, those particles are exfoliated, resulting in low friction and more surface coverage to protect surfaces from galling.
A Comparison Study on Processing ILI Data With Different Filtering Methods
Authors: Liu Zhenhui , Kvarme Stig Olav , Lindøe Odd Einar
Published: September 2018

In-line inspection (ILI) data processing is a crucial process on assessing the remaining capacity of corroded pipelines. It is used to generate the RBP (river bottom profile) or M AV (moving average) file which could be further used in the capacity calculations. There are large uncertainties regarding the qualities of ILI data itself, which are dependent on the accuracies of the ILI tool, the reporting method and the condition of the inspected pipelines et. al. It is thus required that the post-process of the ILI data should not add more uncertainties to the capacity check. Challenges exist on generating reliable RBP/MAV from the ILI data on general base. This paper originates from work during the in-house software development for corroded pipeline tool. Three different algorithms on filtering the ILI data are examined. They are the method recommended by DNV-RP-F101 (with modification), the median filter algorithm and the gaussian filter algorithm. The latter two algorithms are from standard methods for image denoising. A comparison study has been performed with several actual ILI data sets. Finally, conclusions and suggestions have been made, which may provide useful hints for industry application.
Development of Reliable Condition Monitoring Technology for Maritime Using FMECA and Bayesian Network Modeling
Authors: Guan Shan , Knutsen Knut Erik , Alnes Øystein Åsheim
Published: September 2018

Condition monitoring technique has been widely applied in Maritime to ensure safe operation and minimise unscheduled downtime. However, in practice, ship operators need to assure that a failure mode is indeed monitored by the sensor intended for it, and the sensor has sufficient accuracy and precision for its purpose. Additionally, for a reliable condition monitoring technique, issues such as sensors degradation or drift that will reduce the data quality over time must be addressed. All these require that ship owners to select a monitoring system with the best suitable sensors technology while is economically viable. In this paper, tunnel thruster was used as a case study to demonstrate the basic approach to develop a reliable condition monitoring technique through Failure Mode, Effects and Criticality Analysis (FMECA). Based on failure modes, four types of condition monitoring techniques were identified including Vibration Monitoring, Acoustic Emission Monitoring, Wear Debris /Water in Oil Monitoring, and Thermal Monitoring, where vibration monitoring is discussed in detail as an example for defining the sensor specification. For a reliable condition monitoring technique, prediction of sensor reliability will be especially useful in the situation where sensors systems can degrade over time in service. Using temperature sensors as an example, a Bayesian network (BN) modeling approach has been carried out for assessing sensor reliability affected by aging.
On the Optimum Pressure Drop of Axial Kinetic Turbines Operating Within Nozzles
Authors: Moreu Jaime , García-Morato Ricardo , Valle Jesús , de Guzmán Santiago , Terceño Miriam
Published: September 2018

Kinetic turbines harnessing tidal and ocean currents make use, in some designs, of nozzles and/or diffusers. Nozzles come at a cost, but they can help from the structural, hydrodynamic or positioning points of view. In those cases, they might make sense as long as they drive the LCoE (Levelized Cost of Energy) down, which is the ultimate objective of energy-harnessing devices. The design must then optimize the combined performance of both blades and nozzle. However, the interaction between turbine blades and nozzle is not always fully clear, and even less its optimization. A relevant amount of efficiency can be lost if the design spiral is not appropriate.

The authors have suggested in [1] an approach for the optimization of turbines within nozzles. This approach was followed in [2] and validated with model tests. In the approach, the turbine is initially substituted by an actuator disc that applies a radially constant pressure drop. But in these references, the optimum pressure drop in the actuator disc was the same as if there was no nozzle at all, i.e., 4/9ρv2. This is equivalent to considering the nozzle coefficient does not depend on the pressure drop, and thus, on the induced velocity field. Hence it is a somewhat arbitrary assumption.

This paper describes, using actuator disc theory, how nozzles affect the disc optimum pressure drop in uniform flow conditions. The effect of a hub is also analyzed. Then, using a viscous FVM CFD code, the variation of the pressure drop is quantified for two different acceleration nozzles, one suffering flow separation and the other one not. As the pressure drop increases, so does the flow expansion downstream. This rises the average radial component of velocity at the nozzle, increasing the thrust and nozzle coefficient. Therefore the optimum pressure drop goes up compared to that without nozzle. The increment in efficiency that can be obtained with this approach is quantified for the studied nozzles. Finally, the integration of this effect into the blade design is discussed.
Numerical Optimization of Hybrid Panel Joints by Mixed Adhesive/Welded Method on Shipbuilding
Authors: de Vicente Mario
Published: September 2018

The structural method for shipbuilding remains invariant for a century, the introduction of light materials in other fields, aeronautics and automotive, involves saving weight without risking structure failures. The most difficult part is to incorporate these materials in the shipbuilding industry, because the impact in cost and qualified personnel remains as a handicap. The purpose of this study is to review the shipbuilding process specifically the joints between hybrid panels and primary structural elements without a high cost in resources or material. A honeycomb core sandwich is used as a hybrid material, and the optimized mixed joint is raw steel, the clamp is directly welded to the primary members, glued to the panel with two adhesive strengths, and the mathematical formula used to simulate the debonding at the interface is based on the Cohesive Zone Model, proposed by Al-fano and Crisfield. The numerical simulation analyses consist in topological and parametric optimization, and debonding effects are simulated using contact non-linearity and fracture mechanics approaches.
New Concept Design of Large FPSO for Santos Basin - Brazil
Authors: Vilameá Eduardo M. , de Oliveira Allan C. , Ruggeri Felipe , Nishimoto Kazuo
Published: September 2018

The offshore oil fields exploitation, especially giant fields in the Santos basin, brings with it demands for systems capable of operating at ultra-deep waters, with high capacity production wells and high gas/oil ratio (GOR) with large amount of contaminants.

In this scenario, steel catenary risers (SCRs) offer the simplest, most robust and lowest cost solution. However, due to its rigidity compared to flexible risers, this solution is affected by the high dynamic forces imposed on the top of the riser, in consequence of the FPSOs large vertical movement in waves, making difficulties on their application in conventional FPSO hull units. This dynamic problem is caused by environmental conditions of the region, which are harsher than those observed in the Campos Basin.

The reservoir characteristics described above demands high-capacity oil & gas process plants, larger than those used today in the Brazilian offshore. Initial estimates show that these plants require a much larger deck area than conventional platforms and, more than that, a greatest breadth of the vessel.

This paper presents the ULFPSO (Ultra Large Floating Production, Storage and Offloading) concept, developed to satisfy such conflicting requirements. The design process, including the preliminary sizing, physical scale model test and the hull form optimization are discussed and presented in this paper based on a high-capacity process plant case study.
Developing Mk Solutions for Fatigue Crack Growth Assessment of Flaws at Weld Root Toes in Girth Welds
Authors: Zhang Yan-Hui , London Tyler , DeBono Damaso
Published: September 2018

Engineering critical assessment (ECA) is increasingly being used in the offshore industry to determine the maximum tolerable initial flaw size in girth welds for pipelines and risers. To account for the effect of the stress concentration factor (SCF) at the weld toe on the stress intensity factor range, ΔK, a magnification factor, Mk, is used. The existing Mk solutions given in BS 7910 were developed for fatigue assessment of flaws at the toes of fillet and butt welds and may not be suitable for assessing flaws at girth weld root toes, where the weld width is relatively small. On the other hand, for single-sided girth welds, fatigue cracking often initiates from weld toes on the root side, rather than on the weld cap side.

Finite element (FE) modelling was performed to determine a 2D Mk solution for ECA of a flaw at the weld root bead toe. The weld root bead profile was uniquely characterised by five variables including weld root bead width, weld root bead height, hi-lo, weld root bead angle and weld root bead radius. Following a parametric sensitivity study, defect size, weld root bead height and hi-lo were identified as the governing parameters. A total of 6,000 FE simulations was performed and three types of defect models, which covered different combinations of weld root bead height and hi-lo, were generated and analysed. A series of automation scripts were developed in the Python programming language and the Mk solution for each type of defect model was developed and provided in a parametric equation. The accuracy of the 2D Mk solutions was confirmed by the experimental data, in terms of both fatigue crack growth and S-N curves. It was found that the methods and Mk solutions currently recommended in BS 7910 and DNV OS-F101 are inappropriate for assessing a flaw at a girth weld root toe.
Development of a Screening Frequency Scanning Test Method
Authors: Zhang Yan-Hui
Published: September 2018

Fatigue crack growth rates (FCGR) in corrosive environment depends on loading frequency. Frequency scanning testing is often used to determine this effect. However, it is well known that the effect of loading frequency also depends on the magnitude of stress intensity factor range, ΔK. It is generally found that, with decreasing loading frequency, FCGR decreases in the low ΔK regime, increases and then decreases after reaching the saturating loading frequency in the intermediate ΔK regime, and keeps increasing in the high ΔK regime. To accurately characterise the effect of loading frequency on FCGR, several frequency scanning tests are required for a particular application (corrosive environment, material, welding procedure etc), each at a different ΔK level. These are time consuming and expensive tests.

A novel screening frequency scanning test method has thus been developed. The method is similar to the step load fracture toughness test method often used to make a quicker estimate of fracture toughness of material in corrosive environment. In the screening frequency scanning test, both loading frequency and ΔK are changed in steps. At a relatively low and constant ΔK level, loading frequency is reduced in steps, after a certain amount of crack growth. Once the FCGR exhibits decreasing or has achieved a saturating loading frequency with decreasing loading frequency, ΔK is then increased to another higher level and the above process is repeated; the above procedures are repeated until the target maximum ΔK and the lowest loading frequency have been achieved. This method allows an estimate of the effect of loading frequency on FCGR in a large ΔK range using a single specimen. The results of the screening frequency scanning tests demonstrated that this method was feasible and provided a good and quick estimate of the effect of loading frequency on FCGR.
Power and Thrust Capping of Tidal Stream Turbines: A Case Study of the Pentland Firth
Authors: Wang Tuo , Adcock Thomas A. A.
Published: September 2018

It will not be practical for tidal stream turbines to extract all the peaks in energy over the tidal cycle. It is widely assumed that some form of power capping strategy will be required. In this paper we examine this using a 2D shallow water model of tidal hydrodynamics of the Pentland Firth. We argue that in addition to power capping, it is sensible to control the turbines to limit the peak thrust on them. We show that this can lead to a significant reduction in the peak thrust applied to the turbines and smaller changes to the naturally occurring flow rate whilst having a minimal effect of the mean power generated.
Scale Model Investigations on Vibro Pile Driving
Authors: Stein Philipp , Hinzmann Nils , Gattermann Jörg
Published: September 2018

Monopiles installed by impact driving are the preferred system for the foundation of offshore wind turbines in water depths up to 40 m. The vibration technique as alternative installation method has big advantages regarding piling noise and installation time. Much experience exists for the design and installation of impact driven piles. Within the research project ZykLaMP, the lack of experience concerning vibrated monopiles shall be faced by means of large-scaled model investigations regarding the lateral load-bearing behavior.

Therefore, open ended steel pipe piles (L = 2.4 m, Dpile = 0.6 m) are installed into dense sand by means of impact and vibratory pile driving and then subjected to cyclic lateral loading. This paper focusses on pile driving predictions and measurements during the installation process.

Pile driving post-predictions were carried out based on a simple force equilibrium approach. Model piles were installed using two different vibro hammers with different eccentric moments and one impact hammer. Measurements of strains and accelerations were carried out to investigate dynamic movements during pile driving. Earth pressure transducers were used to investigate the development of soil stresses due to the installation process.

Measurements show that even at high acceleration amplitudes a refusal to vibratory driving may occur at a certain penetration depth. Soil stresses in the vicinity of the pile decrease to about 50 % due to vibratory driving which is one reason for the friction fatigue phenomenon.

Drivability studies using the force equilibrium model give rough predictions about whether or not a pile can be driven to a certain penetration depth but are quite sensitive to input parameters. For the model tests, post-predictions gave reasonable results.
Validated Methodology for Calculating Fatigue Capacity of Deepwater Umbilicals
Authors: Connaire Adrian , Doynov Krassimir , Nestor Ruairi , Krishnan Venkat
Published: September 2018

Steel tube umbilical designs are becoming more complex and are being deployed in increasingly severe environments. Umbilical designs can now accommodate up to 3-inch diameter steel tubes for chemical and hydraulic injection, up to four layers of armoring, multiple electrical cables and fiber optic lines. Large power transmission cables are also being incorporated in umbilical constructions. This is leading to ever increasing umbilical mass, radial loads, pressure loads and increased demands on the designer to demonstrate adequate fatigue capacity.

A method has been developed for predicting the fatigue response of deepwater umbilicals, particularly for umbilicals subject to high tension and bending loads. The method involves predicting cyclic stress in the umbilical components (steel tubes or power cables) using an industry standard, general purpose numerical tool. It comprehensively accounts for the complex relationships between umbilical curvature, tension, inter-layer contact forces and tube stress variation. This paper describes the validation of the method against measured data obtained from full scale fatigue tests performed on two deepwater umbilicals.

A key feature of the method relates to the construction and verification of suitable finite element (FE) models and the simulation of fatigue conditions. For the validation of the models, results from the full scale dynamic umbilical test cases incorporating bend stiffeners and loading arms are used, which demonstrate umbilical hysteretic behavior under cyclic bending loads. Hysteretic stress-curvature loops obtained from strain gauge readings for various tube locations within the bend stiffener regions for two umbilical constructions with significantly different lay-up configurations and fatigue stress regimes are used for comparison to strain predictions from the FE models.

A significant advantage of the modelling and analysis methods described in this paper is that it employs the widely-used industry standard numerical FE tool, Abaqus, for the modelling and analysis of the umbilical. Key features and insights from the modelling, analysis approach and validation against the results of a deepwater umbilical dynamic test program are described. A robust and efficient method for the independent assessment of the fatigue capacity of deepwater umbilicals is demonstrated.
Quantifying Multicollinearity in Ship Manoeuvring Modeling by Variance Inflation Factor
Authors: Wang Zi-Hao , Zou Zao-Jian
Published: September 2018

Parameter drift is a tricky problem in system identification, and collinearity in the identified model is considered to be its cause in the field of statistical learning. To diminish the parameter drift and identify the model parameters more accurately, a better understanding of the characteristics of collinearity is necessary. System identification is one of the effective modeling methods in the study of ship manoeuvrability. This paper aims at quantifying and analyzing the collinearity in the modeling of ship manoeuvring motion by using Variance Inflation Factor (VIF). By utilizing the multiple datasets including those from zigzag and turning tests and the combinations of manoeuvres, as well as the data processed by D-optimizing design or difference method, the VIF is applied to quantify the severity of collinearity of different model structures. The results show that the selected manoeuvring models have high collinearity under the data of single standard manoeuvre. The pre-processed test data and an appropriate model structure can alleviate the collinearity, hence to diminish the parameter drift. However, the collinearity of the selected models cannot be eliminated. Some suggestions are given for selecting more appropriate training data and mathematical model structures of ship manoeuvring to accurately estimate the model parameters.
Response of an Aluminum Stiffened Plate Under Extreme Slamming Loadings
Authors: Liu Bin , Villavicencio R. , Liu Kun , Zhu Ling , Guedes Soares C.
Published: September 2018

The slamming phenomenon often occurs when the bottom of a ship hits the seawater with a relatively high velocity in irregular waves. In extreme sea conditions, the slam induced dynamic loads can be quite large resulting in local structural damages or global deformation of the panels, in particular when ships face head sea waves with high forward speed. The paper presents finite element simulations of an aluminum stiffened plate subjected to extreme slamming loadings. The selected plate is commonly used for the design and construction of the hull of high-speed vessels. The simulations are performed with the explicit LS-DYNA finite element solver and analyze the large plastic deformation of the stiffened plate. The effect of the heat affected zone due to the welding is also assessed using the mechanical properties of an aluminum alloy grade 5083-H116. The outcomes of this study identify the parameters that should have practical importance when estimating the extent of structural deformation due to slamming loads.