bluuebunny/crossref_metadata_2025 huggingface dataset:
Radial basis function surrogate model-based optimization of guardrail post embedment depth in different soil conditions
Authors: Ozcanan Sedat , Atahan Ali Osman
Published: May 2019

For guardrail designers, it is essential to achieve a crashworthy and optimal system design. One of the most critical parameters for an optimal road restraint system is the post embedment depth or the post-to-soil interaction. This study aims to assess the optimum post embedment depth values of three different guardrail posts embedded in soil with varying density. Posts were subjected to dynamic impact loads in the field while a detailed finite element study was performed to construct accurate models for the post–soil interaction. It is well-known that experimental tests and simulations are costly and time-consuming. Therefore, to reduce the computational cost of optimization, radial basis function–based metamodeling methodology was employed to create surrogate models that were used to replace the expensive three-dimensional finite element models. In order to establish the radial basis function model, samples were derived using the full factorial design. Afterward, radial basis function–based metamodels were generated from the derived data and objective functions performed using finite element analysis. The accuracy of the metamodels were validated by k-fold cross-validation, then optimized using multi-objective genetic algorithm. After optimum embedment depths were obtained, finite element simulations of the results were compared with full-scale crash test results. In comparison with the actual post embedment depths, optimal post embedment depths provided significant economic advantages without compromising safety and crashworthiness. It is concluded that the optimum post embedment depths provide an economic advantage of up to 17.89%, 36.75%, and 43.09% for C, S, and H types of post, respectively, when compared to actual post embedment depths.
Oil-treated pleated fibrous air filters for motor vehicle engine intake application
Authors: Maddineni Ajay Kumar , Das Dipayan , Damodaran Ravi Mohan
Published: May 2019

In this work, oil-treated pleated fibrous air filters were developed, characterized, and evaluated for motorcycle engine intake application. The effect of pleat geometry on the filtration performance was examined. Pleat pitch and pleat height were found to play important roles in determining the filtration efficiency, pressure drop, and dust holding capacity. A pleated fibrous filter prepared with optimum levels of pleat pitch and pleat height showed the best filtration performance. The treatment to the pleated filter by viscous oil yielded remarkably higher dust holding capacity and filtration efficiency, both at cleaned and clogged conditions. A statistical analysis revealed that the weight of oil played a significant role in deciding the filtration performance. The oil-treated pleated filter was installed in a commercial air intake system and its filtration performance was assessed. The filter element displayed a significant delay in evolution of pressure drop during dust loading as compared to the untreated one. However, the difference in filtration efficiency between the oil-treated and untreated filter elements was not found to be too high. Nevertheless, both of them met the standard filtration performance as per the best practices followed by the automotive industry. Overall, the oil treatment to cellulosic filters was found to be highly advantageous for motorcycle application. Practical implications of such air filter system were discussed in terms of service life, fuel consumption, and CO2 emission during filter life time.
Three-dimensional modeling and time-delay stability analysis for robotics docking simulation
Authors: Sazawal Prateek , Choukroun Daniel , Benninghoff Heike , Gill Eberhard
Published: May 2019

Hardware-in-the-loop simulations of two interacting bodies are often accompanied by a time delay. The time delay, however small, may lead to instability in the hardware-in-the-loop system. The present work investigates the source of instability in a two spacecraft system model with a time-delayed contact force feedback. A generic compliance-device-based contact force model is proposed with elastic, viscous, and Coulomb friction effects in three dimensions. A 3D nonlinear system model with time delay is simulated, and the effect of variations in contact force model parameters is studied. The system is then linearized about a nominal state to determine the stability regions in terms of parameters of the spring-dashpot contact force model by the pole placement method. Furthermore, the stability analysis is validated for the nonlinear system by energy observation for both the stable and unstable cases.
Evaluation of skin-mounted sensor for head impact measurement
Authors: Tiernan Stephen , Byrne Gary , O’Sullivan David Michael
Published: May 2019

The requirement to measure the number and severity of head impacts in sports has led to the development of many wearable sensors. The objective of this study was to determine the reliability and accuracy of a wearable head impact sensor: xPatch, X2Biosystems, Inc. The skin-mounted sensor, xPatch, was fixed onto a Hybrid III headform and dropped using an impact test rig. A total of 400 impacts were performed, ranging from 20g to 200g linear acceleration, and impact velocities of 1.2 - 3.9 m/s. During each impact, the peak linear acceleration, angular velocity and angular acceleration were recorded and compared to the reference calibrated data. Impacts were also recorded using a high-speed video camera. The results show that the linear acceleration recorded by the xPatch during frontal and side impacts had errors of up to 24% when compared to the referenced data. The angular velocity and angular acceleration had substantially larger errors of up to 47.5% and 57%, respectively. The location of the impact had a significant effect on the results: if the impact was to the side of the head, the device on that side may have an error of up to 71%, thus highlighting the importance of device location. All impacts were recorded using two separate xPatches and, in certain cases, the difference in angular velocity between the devices was 43%. In conclusion, the xPatch can be useful for identifying impacts and recording linear accelerations during front and side impacts, but the rotational velocity and acceleration data need to be interpreted with caution.
A motivational driver model for the design of a rear-end crash avoidance system
Authors: Mozaffari Hamed , Nahvi Ali
Published: May 2019

A motivational driver model is developed to design a rear-end crash avoidance system. Current driver assistance systems use engineering methods without considering psychological human aspects, which leads to false activation of assistance systems and complicated control algorithms. The presented driver model estimates driver’s psychological motivations using the combined longitudinal and lateral time to collision, the vehicle kinematics, and the vehicle dynamics. These motivations simplify both autonomous driving algorithms and human-machine interactions. The optimal point of a motivational multi-objective cost function defines the decision for the autonomous driving. Moreover, the motivations are used as risk assessment factors for driver–machine interaction in dangerous situations. The system is evaluated on 10 human subjects in a driving simulator. The assistance system had no false activation during the tests. It avoided collisions in all the rear-end crash avoidance scenarios, while 90% of human subjects did not.
Performing financialized subjectivities in household economy manuals under state socialism and neoliberal capitalism
Authors: Samec Tomáš , Hájek Martin
Published: May 2019

This article explores how financialized subjectivities have been performed in household economy manuals under two successive socio-economic regimes in the former Czechoslovakia and the current Czech Republic: state socialism and neoliberal capitalism. Drawing on a layered performativity framework, we studied how rhetoric, devices and instructions used in manuals construct households into self-reliant actors who embrace financial products. We found that subjects were already being financialized by the manuals of the socialist era, particularly those from the 1980s. The main change concerned the treatment of temporality and the occurrence of calculative devices. Our findings challenge the idea that financialization has emerged under the regime of neoliberal capitalism and implies that financialization is part of a longer trend in modern economic governance.
The impact of disabilities on earning or learning in Australia and the implications for career development
Authors: Athanasou James A , Murphy Gregory C , Mpofu Elias
Published: May 2019

This paper utilises the national Survey of Disability Ageing and Carers to summarise the educational disadvantages and vocational inequalities for those with disabilities in Australia. Amongst persons with a disability, there is a decidedly lower rate of school completion. Distinctly fewer persons with a disability obtain degrees. Income is markedly reduced. Labour force participation is significantly lower, and the unemployment rate in 2015 was twice that of those without a disability. Alternate duties were provided in only 2% of cases and workplace accommodation made in 4% of instances. Supported employment was available in only 2.2% of cases. A disconcerting conclusion is that, over the past decade, the unemployment rate for those with a disability has been consistently higher. Suggestions are made for career development professionals to reverse some of the disadvantages reported.
Qualitative exploration of career adaptability of Turkish adolescents
Authors: Ozdemir Nurten Karacan
Published: May 2019

This article reports on a qualitative study that uses a phenomenological approach to investigate the differences between adolescents with high and low career adaptability levels, regarding adaptive strategies and needs. The sample included students categorized as above the 75th percentile and in the bottom 25th percentile according to their scores on the Career Adapt-Abilities Scale. The data were gathered from 20 high school students (12 male and 8 female) from Ankara, Turkey, using career construction interviews. A content analysis revealed that exploration (self and occupations), persistence, and inquisitiveness were frequently observed in the high career adaptability group. On the other hand, lack of persistence, lack of confidence, and emotion-focused problem solving were prominent in the low career adaptability group. The results suggest the need for career education programs in schools that promote confidence and problem-solving skills for Turkish adolescents, especially those low on adaptability.
Linking succession planning to employee performance: The mediating roles of career development and performance appraisal
Authors: Ali Zulqurnain , Mahmood Babak , Mehreen Aqsa
Published: May 2019

Drawing on social exchange theory, the objectives of the study were to examine how succession planning relates to employee performance and assess whether career development and performance appraisal mediate this relationship. Using survey methodology, data were collected from permanent employees at several commercial banks (N = 239; 62% male). Structural equation modeling tested the proposed model. The results suggested that succession planning had a significant, positive relationship with employee performance, and both career development and performance appraisal mediated the relationship. The current study extends the social exchange theory by identifying the relationship between succession planning and employee performance in the context of the banking sector. The study suggests that if bank management builds a pool of skilled employees through succession planning and performance management, it can ameliorate inappropriate appointments in response to sudden vacancies and retirement of employees.
Fieldwork placement outcomes for international higher education students: A systematic literature review
Authors: Lee Den-Ching A , Jian Mengying , Sora Gepi , Haines Terry P
Published: May 2019

Fieldwork experiences can be particularly challenging for international, higher education students, as they face language and cultural difficulties, which can affect their academic progress and their fieldwork interactions with supervisors and clients. This review synthesised findings from 27 studies referring to higher education courses that employed fieldwork placements. The aims were to examine the effectiveness of placement support programs and to collate strategies that international students and/or placement supervisors felt might improve placement outcomes. Results identified a large number of activities that could be used to improve placement outcomes. However, due to the lack of comparison or observational data, it is recommended that future studies be better controlled and include longitudinal studies to better identify the effective aspects of support programs. In this way, program and policy-making will be better informed.
Predicting Academic Achievement and Counselling for Course Selection: An Examination of the Effectiveness of the Differential Aptitude Tests in Forecasting Year 12 Success
Authors: Edwards Roger
Published: May 2019

There is increasing tendency to use the Differential Aptitude Tests (DAT) for course and career counselling with students in independent schools in Australia. The OAT profile and explanatory notes may also be forwarded to students and/or parents and it is of particular concern that the full explanation of means of interpreting the profile is often not clear to the naive client. Many clients view the profile as a combination of IQ report and predictor of future academic success. To provide professional counsellors with unequivocal evidence to support their explanations to such clients, and as entry to tertiary and to many TAPE courses in Australia, is by academic achievement score, the present study examined the predictive value of the DAT for academic achievement at the end of Year 12. It was concluded that the DAT may have some value in predicting marginal variations in academic achievement, over and above that predicted by measures of general mental ability, but that individual counselling on the nature of the DAT profile is needed to demonstrate to the naive client both the distorting effect of the CSA subtest and the inappropriateness of the view that any of the DAT measures may be seen as predictors of Tertiary Entrance Score.
Software Reviews
Authors: Wiseman Richard
Published: May 2019

As a first step towards preparation of a collection of reviews of computer-assisted career guidance packages, guidelines for evaluation of such packages were published in the Journal (Vol. 2, No. 1, pp. 40–42). Comments on the guidelines, which were prepared by Dr Esther Care, were sought from readers. These and other guidelines formed the basis of a document sent to potential reviewers of packages for this special edition.

The process began by consulting practitioners, publishers and others knowledgeable in the field to ensure that as wide a range as possible of systems available in Australia would be covered in the reviews. Letters were sent to publishers and distributors requesting descriptive information about the nature of each system, its intended clients, cost and hardware requirements. For each system, a representative list of purchasers was requested from the distributor or publisher. These lists were used to ensure that a wide range of practitioners and regions of Australia would be encompassed in the reviews. We are also particularly pleased to have information from two neighbouring countries, New Zealand and Singapore, about systems developed and in use there.

From the lists provided, two purchasers of each system were selected from different types of organisations and from different states or territories. Letters inviting reviews were sent, together with the document of suggested guidelines for comment. It was stressed that the guidelines were no more than that, and that comment in any form would be welcome. Not all potential reviewers approached were able to undertake the task and a few “reserves” were called upon. Nevertheless a good cross-section of types of users and almost all regions of Australia are represented in the replies. The entries in the Journal are either directly as submitted or have been paraphrased from the summary comments made in response to the guidelines. In each of the latter cases, the paraphrased material was confirmed by the reviewer as an accurate reflection of the comments made.
Gendered Perceptions of Talent and Planned Participation in Mathematics
Authors: Watt Helen , Bornholt Laurel
Published: May 2019

An investigation of students’ perceptions of talent in relation to mathematics showed that gender stereotyped perceptions of talent were a determining factor in their planned mathematics courses in senior high school. Furthermore perception of talent affected students’ intended careers which also revealed gender imbalances in participation according to the level of mathematics required, as rated by six senior teacher educators from two universities in Sydney. The Year 10 students in Advanced and Intermediate courses were from coeducational government schools in an upper middle-class metropolitan area of Sydney. Actual performance on a standardised mathematics test was used to measure students’ achievement, and perception of talent and predicted mathematics participation were ascertained through use of a questionnaire. Despite similar performance on the test, boys perceived themselves as more talented than girls, and also planned to participate in the higher levels of mathematics more than girls, both in the Higher School Certificate and their intended career.
Career Development in the New Millennium
Authors: Ellyard Peter
Published: May 2019

In 1994, Australian people are becoming optimistic about the future after five years of pessimism. The way people view their personal and working futures is a reflection of both their experience and of the way they naturally think. In the 1980s – the decade of downsizing – organisations did not have much room for lateral thinkers. Vision vanished from our enterprises along with a concern for the long term, and there was very little commitment to research and development and to organisational learning. Much of the capacity to adapt, innovate and change went too. Now the pendulum is swinging back the other way. Vision is coming back.
Efficacy of Motivational Interviewing to Enhance Advance Directive Completion in Latinos With Chronic Illness: A Randomized Controlled Trial
Authors: Nedjat-Haiem Frances R. , Cadet Tamara J. , Amatya Anup , Thompson Beti , Mishra Shiraz I.
Published: May 2019

Background:

End-of-life (EOL) care for Latinos with chronic illness is a critically important problem. Latinos with chronic illness suffer worse health outcomes and poorer quality of care due to various issues occurring in care delivery systems. Latinos are less likely than non-Hispanic whites to prepare an advance directive (AD) for health-care decision-making that impacts treatment decisions for when EOL is near. Advance care planning (ACP) interventions tailored specifically for Latinos have rarely been implemented.

Objective:

The primary aim examines whether a motivational interviewing (MI) intervention increased rates of AD documentation among older Latinos. The secondary aim was to examine whether MI improved communication with providers and family members.

Methods:

We pilot tested a randomized controlled trial with older Latinos >50 years with one or more chronic illnesses, including cancer. Participants were randomly assigned to usual care (UC) receiving ACP education alone versus treatment (TX), which received ACP education, plus MI counseling including interactive decisional support, emotional support, and barrier navigation.

Results:

Results of logistic regression indicate TX group participants were significantly more likely to document an AD than UC, however were less ready to talk with health-care providers or family members. Those reporting navigational barriers for talking about dying is difficult showed a significant negative relationship for AD completion even with significant intervention effects.

Conclusion:

When using MI to motivate individuals toward ACP EOL conversations other factors are important to consider. Further research is needed, especially among Latinos to understand best practices for ACP education and counseling for EOL care.
Intellectual Equipoise and Challenges: Accruing Patients With Advanced Cancer to a Trial Randomizing to Surgical or Nonsurgical Management (SWOG S1316)
Authors: Deutsch Gary B. , Deneve Jeremiah L. , Al-kasspooles Mazin F. , Nfonsam Valentine N. , Gunderson Camille C. , Secord Angeles Alvarez , Rodgers Phillip , Hendren Samantha , Silberfein Eric J. , Grant Marcia , Sloan Jeff , Sun Virginia , Arnold Kathryn B. , Anderson Garnet L. , Krouse Robert S.
Published: May 2019

Background:

Prospective, randomized trials are needed to determine optimal treatment approaches for palliative care problems such as malignant bowel obstruction (MBO). Randomization poses unique issues for such studies, especially with divergent treatment approaches and varying levels of equipoise. We report our experience accruing randomized patients to the Prospective Comparative Effectiveness Trial for Malignant Bowel Obstruction (SWOG S1316) study, comparing surgical and nonsurgical management of MBO.

Methods:

Patients with MBO who were surgical candidates and had treatment equipoise were accrued and offered randomization to surgical or nonsurgical management. Patients choosing nonrandomization were offered prospective observation. Trial details are listed on www.clinicaltrials.gov (NCT #02270450). An accrual algorithm was developed to enhance enrollment.

Results:

Accrual is ongoing with 176 patients enrolled. Most (89%) patients chose nonrandomization, opting for nonsurgical management. Of 25 sites that have accrued to this study, 6 enrolled patients on the randomization arm. Approximately 59% (20/34) of the randomization accrual goal has been achieved. Patient-related factors and clinician bias have been the most prevalent reasons for lack of randomization. An algorithm was developed from clinician experience to aid randomization. Using principles in this tool, repeated physician conversations discussing treatment options and goals of care, and a supportive team–approach has helped increase accrual.

Conclusions:

Experience gained from the S1316 study can aid future palliative care trials. Although difficult, it is possible to randomize patients to palliative studies by giving clinicians clear recommendations utilizing an algorithm of conversation, allotment of necessary time to discuss the trial, and encouragement to overcome internal bias.
Ten-Year Trends of Utilization of Palliative Care Services and Life-Sustaining Treatments and Hospital Costs Associated With Patients With Terminally Ill Lung Cancer in the United States From 2005 to 2014
Authors: Hwang Jinwook , Shen Jay , Kim Sun Jung , Chun Sung-Youn , Kioka Mutsumi , Sheraz Faizan , Kim Pearl , Byun David , Yoo Ji Won
Published: May 2019

Background:

Palliative care services and life-sustaining treatments are provided to dying patients with lung cancer in the United States. However, data on the utilization trends of palliative care services and life-sustaining treatments of dying patients with lung cancer are not available.

Methods:

This study was a retrospective analysis of the National Inpatient Sample data (2005-2014) and included patients with lung cancer, aged ≥ 18 years, who died in the hospitals. Claims data of palliative care services and life-sustaining treatments that contained systemic procedures, local procedures, or surgeries were extracted. Compound annual growth rates (CAGRs) using Rao-Scott correction for χ2 tests were used to determine the statistical significance of temporal utilization trends of palliative care services and life-sustaining treatments and their hospital costs. Multilevel multivariate regressions were performed to identify factors associated with hospital costs.

Results:

A total of 120 144 weighted patients with lung cancer died in the hospitals and 41.9% of them received palliative care services. The CAGRs of systemic procedures, local procedures, surgeries, palliative care services, and hospital cost were 3.42%, 3.48%, 6.08%, 18.5%, and 5.0% (all P < .001), respectively. Increased hospital cost was attributed to systemic procedures (50.6%), local procedures (74.4%), and surgeries (68.5%; all P < .001), respectively. Palliative care services were related to decreasing hospital costs by 28.6% ( P < .001).

Conclusion:

The temporal trends of palliative care services indicate that their utilization has increased gradually. Palliative care services were associated with reduced hospital costs. However, life-sustaining treatments were associated with increased hospital costs.
How children develop their ability to combine words: a network-based approach
Authors: Barceló-Coblijn Lluís , Irurtzun Aritz , Real Puigdollers Cristina , López-Navarro Emilio , Gomila Antoni
Published: May 2019

A new way to study and represent early syntactic development is introduced that offers a promising avenue to improve on standard cumulative approaches to language learning. The analysis is inspired by complex network theory and explores an important issue in psycholinguistics: how children combine words syntactically. To this end, the article exploits the longitudinal data of multiple individual studies stored and publicly available in the CHILDES database. This analysis proves useful in two regards: in coincidence with previous approaches to syntactic development, it reveals a similar linear–nonlinear pattern of syntactic development (a combination of linear periods interrupted by abrupt transitions) in typical children regardless the language they are acquiring. It also provides a straightforward objective measure of syntactic impairment in atypically developing children. A striking difference between typical and atypical children lies in the connectivity of functional words, which suddenly become hubs but only in typical development. Our technique offers a formal measure of impairment with respect to typical syntactic development, which goes beyond the standard notion of retardation in development, for the Down syndrome condition.
Sexual Offense Legislation Across the Pond: A Review of Community Sentiment Toward the United Kingdom’s Implementation of Sarah’s Law
Authors: Zgoba Kristen M. , Cowan Devin
Published: May 2019

Within both the United States and the United Kingdom, laws have been implemented that govern the behavior of individuals convicted of certain sexually based offenses. Thus, research has naturally gravitated toward examining the public perceptions of these laws. Although both the United States and United Kingdom have laws regarding convicted sex offenders, and although these laws vary, research into the perceptions of these laws has largely been concentrated within the United States. The current study seeks to fill this gap through a survey of U.K. residents that assesses their perceptions of the implementation of Sarah’s Law. Respondents were gathered through convenience sampling methods in both Bristol and London, England ( n = 140). Overall, respondents were fairly supportive of Sarah’s Law and its current implementation. However, as opposed to respondents in the United States, U.K. respondents were also open to the idea of providing a degree of privacy to convicted sex offenders and were more tolerant of sexual offenders living near them. Finally, age, race, and parental status of the respondents were found to be statistically significant predictors among four identified dependent variables testing support of the law. Implications from these results are discussed, and a direction for future comparative research is highlighted.
Numerical calculation of the elastic field in a half-space using bilinear elements
Authors: van der Wekken CD , Vollebregt EAH
Published: May 2019

This paper considers the problem of computing the stresses inside an elastic half-space for prescribed normal and shear surface tractions. It is shown that piecewise constant loading elements result in numerical artifacts near the element boundaries. This is resolved by approximating the surface loading using bilinear elements. Three different implementations are considered, namely Dydo and Busby’s approach on the basis of potential functions, a new approach on the basis of explicit formulas, and using numerical integration. The results are thoroughly cross-validated, revealing subtle issues in the earlier works. These new results are then used to establish the reliability of a practical way forward, using the piecewise constant approach, computing values at element centers only.
Thermodynamic behavior of functionally graded sandwich plates resting on different elastic foundation and with various boundary conditions
Authors: Mekerbi Mohamed , Benyoucef Samir , Mahmoudi Abdelkader , Tounsi Abdelouahed , Bousahla Abdelmoumen A , Mahmoud SR
Published: May 2019

The thermodynamic behavior of functionally graded (FG) sandwich plates resting on Winkler/Pasternak/Kerr foundations and with various boundary conditions is studied in this paper by using a refined 2D plate theory. The displacement field of the present theory contains undetermined integral forms and involves only four unknowns to derive. The plate is considered to be subject to a time harmonic sinusoidal temperature field across its thickness. Three types of foundation are studied. Each is described by a mathematical model. Different boundary conditions are used to study the thermodynamic behavior of sandwich plates on elastic foundations. The present model gives an incredible concurrence with the accessible literature. The adaptability of the proposed theory is handled by considering the impact of different parameters like time parameter, foundation parameters and deflection on the bending response of sandwich plate through several illustrations.
Pathway Interactions Based on Drug-Induced Datasets
Authors: Kim Shinuk
Published: May 2019

In this study, we identified enrichment pathway connections from MCF7 breast cancer epithelial cells that were treated with 87 drugs. We extracted drug-treated samples, where the sample size was greater than or equal to 5. The drugs included 17-allylamino-geldanamycin, LY294002, trichostatin A, valproic acid, sirolimus, and wortmannin, which had sample sizes of 11, 8, 7, 7, 7, and 5, respectively. We found meaningful pathways using gene set enrichment analysis and identified intradrug and interdrug pathway interactions, which implied the influence of drug combination. Among the top 20 enrichment pathways that were wortmannin induced, there were a total of 37 intradrug pathway interactions via common genes. Thirty-seven pathway interactions were induced by valproic acid, 11 induced by trichostatin A, 20 induced by LY294002, and 59 induced by sirolimus, all via common genes. The number of interdrug-induced pathway interactions ranged from one pair of pathways to 23. The pair of ERBB_SIGNALING and INSULIN_SIGNALING pathways showed the highest score from a pair of 2 individual drugs. The highest number of pathway interactions was observed between the drugs 17-allylamino-geldanamycin and LY294002.
Steady-state performance analysis of misaligned double-layered porous journal bearings under coupled-stress lubrication with slip flow and additives percolation effect
Authors: Some Shitendu , Guha Sisir K
Published: May 2019

The aim of this paper is to address the effect of misalignment of the double-layered porous journal bearing on the steady-state performance analysis under coupled-stress lubrication with velocity phenomenon at the fine porous interface. Here, the misalignment caused by shaft displacement, e.g. axial (vertical displacement) and twisting (horizontal displacement) is considered. This analysis includes velocity slip phenomenon on the basis of Beavers-Joseph criteria. Moreover, the present analysis also focuses on the percolation effect of the additives into the pores of the porous layers. Steady-state film pressures are obtained by solving the modified Reynolds equation based on the coupled-stress lubrication theory. Under various parametric conditions, pressure profiles in the film region are discussed and demonstrated in the graphical form. Using these film pressure values, steady-state characteristics in terms of bearing load carrying capacity, attitude angle, frictional parameter, side leakage and misalignment moment are evaluated at various parametric conditions and represented in the graphical form.
Analytical analysis of a rigid rotor mounted on three hydrostatic pads lubricated with micropolar fluids
Authors: Benariba Aboubakeur , Bouzidane Ahmed , Thomas Marc
Published: May 2019

Analytical analysis of rigid rotor set vertically, supported by a new hydrostatic squeeze film damper consisting in three hydrostatic pads fed through three capillary restrictors operating with micropolar lubricant is presented. The modified Reynolds equation is obtained using the micropolar lubrication theory and solving it analytically. The calculation of the flow rate, dimensionless vibratory amplitude and amplitude of transmitted forces are determined by resolving the equations of rotor motion using nonlinear methods. It has been observed that a rigid rotor operating with micropolar lubricant shows an increase in the value of transmitted forces at high speeds and a reduction in the value of vibratory response at critical speed when compared to a corresponding similar rigid rotor operating with Newtonian lubricant.
Rheological behavior of the lubricants favoring the formation of thin layers by selective transfer in the frictional couples
Authors: Ilie Filip
Published: May 2019

During the friction process of certain materials and in the presence of some adequate lubricants (technical glycerin), the wear phenomenon manifests as a material transfer from an element of a frictional couple on the other, in the contact areas (forming a selective layer), and therefore, can function in conditions of selective transfer. This phenomenon lasts until it reaches an optimal thickness, and after that, the transferred layer may return totally or partially to the initial element. In the contact points of the frictional couples that function with the selective transfer, several physical–chemical processes take place that favor the phenomenon. An important role in the functioning of the frictional couples with a selective transfer is rheological behavior that it has the lubricant. This paper analyzes the behavior and some of the rheological properties of the technical glycerin in the frictional couples what functioning with the selective transfer, technical glycerin being the lubricant that contributes sure, to the triggering of this phenomenon.
Modeling and prediction of the running-in behavior of the piston ring pack system based on the stochastic surface roughness
Authors: Gu Chunxing , Zhang Di
Published: May 2019

This paper proposes an efficient numerical approach to predict the initial running-in process of piston ring pack/cylinder liner system. A combined mixed lubrication and wear model coupled with an oil transport model was developed. In order to predict the hydrodynamic pressure efficiently, two improved methodologies, including the Fischer-Burmsister-Newton-Schur (FBNS) approach and the Grid Refinement (GR) strategy, were adopted. Meanwhile, in order to take into account the effect of skewness, Weibull distribution function was adopted to characterize the asperity height distribution. Predicting the wear of cylinder liner was based on the Archard's wear law. The influences of asperity plastic deformation and wear on asperity height distribution were considered. The results show that the developed model can well predict the initial running-in behavior of piston ring pack/cylinder liner system under an engine-like condition.
Armed conflict, military expenditure and international tourism
Authors: Khalid Usman , Okafor Luke Emeka , Aziz Nusrate
Published: May 2019

This article uses a gravity model to explore whether military spending has any moderating effect on the link between armed conflict and international tourist flows. The data set consists of a panel of 188 countries over the period 1995 to 2015. We show that the moderating effect of military spending depends on the levels of relative military spending as well as geographical location. Specifically, in the presence of armed conflict, ‘moderate’ level of relative military spending helps to promote the international tourism attractiveness of destination countries, whereas ‘high’ level of relative military spending cannot reverse the negative impact of armed conflict, it rather fuels the problem. In general, countries in regions such as Southeast Asia that allocate ‘moderate’ amount of resources for security attract more international tourists relative to countries in regions, such as the Middle East and North Africa, that spend a larger share of GDP on security.
Embedding interagency working between schools and mental health specialists: A service evaluation of the Mental Health Services and Schools and Colleges Link Programme workshops
Authors: Cortina Melissa A. , Shipman Judith , Saunders Felicity , Day Laurie , Blades Rachel , Smith Jaime , Wolpert Miranda
Published: May 2019

There is increasing focus on the need for schools to work more effectively with specialist mental health providers, but there have been historic challenges in embedding closer interagency working. This article reports the results of a service evaluation of a 2-day workshop designed to facilitate improved working between schools and children and young people’s mental health services (CYPMHS). Mental health leads from 255 schools, mental health professionals and other key stakeholders all took part in one of 26 two-day workshops across the United Kingdom. The impact on interagency working was examined using changes in pre- and post-survey results, changes in self-reported aspects of interagency working and 10 local reviews of practice. The pre–post questionnaires showed improvements in interagency working (e.g. 55% of school leads reported being in ‘monthly’ or ‘continuous’ contact with the National Health Service (NHS) CYPMHS1 at follow-up, compared with 24% at baseline). The group-completed CASCADE framework showed an overall increase in collaborative working, although some areas continued to report significant challenges such as in relation to common outcome measures. The local reviews found positive changes in interagency working, in terms of building relationships, improved communication and sharing good practice. This service evaluation of the workshops found some evidence of improved interagency working between schools and CYPMHS, but more controlled research is needed to consider generalisability and scalability.
Combustion system optimization for dimethyl ether using a genetic algorithm
Authors: Zubel Marius , Ottenwälder Tamara , Heuser Benedikt , Pischinger Stefan
Published: May 2019

Dimethyl ether is a gaseous fuel which can easily be liquefied under moderate pressures. Its high reactivity makes it suitable for combustion in a compression ignition engine, and due to the high oxygen content, its combustion is virtually free of soot. The high oxygen content and low density of dimethyl ether lead to a lower volumetric heating value compared to Diesel fuel. Therefore, the hydraulic flow rates of the injectors have to be increased with larger nozzle holes. The influence of larger nozzle holes on the dimethyl ether spray formation and ignition are presented in this article. Experimental investigations were conducted at a constant-pressure vessel with optical access and with a single-cylinder research engine. Subsequently, a numerical optimization of the piston bowl and injector nozzle has been carried out. A very fast air/fuel mixture formation with dimethyl ether was observed, which leads to a lean combustion with small nozzle diameters. With increasing nozzle diameters, the combustion moves toward stoichiometric conditions and with very large diameters to rich combustion conditions. The ignition delay for small diameters is mostly dominated by the lean mixture, and for large diameters, the ignition delay is strongly influenced by cooling effects. For the optimization, the oxidation potential number was maximized, which proved suitable to simultaneously increase efficiency and reduce emissions. A conventional ω-shaped bowl and a step bowl have been optimized, and large bowl diameters were found to be beneficial for dimethyl ether combustion. Furthermore, nozzle diameters around 150 µm showed the most promising results. Compared to the dimethyl ether reference, the simulations with the optimized ω-shaped bowl showed a power increase of 2.7%. Experimentally, the optimized ω-shaped bowl in combination with the reference injector showed an efficiency increase by more than 1% at 2000 r/min full load compared to the dimethyl ether reference.
Ovulatory Shifts in Sexual Desire But Not Mate Preferences: An LH-Test-Confirmed, Longitudinal Study
Authors: van Stein K. R. , Strauß B. , Brenk-Franz K.
Published: May 2019

The presented data are part of a longitudinal within-subject study designed to examine ovulatory shifts in human sexuality in a diverse German sample using validated questionnaires. The final sample consists of 78 individuals (76 female, 2 agender) who declared to be mainly or exclusively attracted to males. Questionnaires were completed anonymously online at three cycle phases. Following the gold standard, the fertile window was calculated through the reverse cycle day method and confirmed via urinary tests detecting luteinizing hormone. The questionnaire included the Sexual Desire Inventory, Dresdner Body Image Inventory, the Revised Sociosexual Orientation Inventory, and an adjective list to measure mate preferences. One hundred eighty-four questionnaires were included in the data analysis using linear mixed models. Findings support previous research reporting heightened sexual desire and an improved body image during the fertile window. No shifts were found for mate preference or sociosexual orientation, thus adding to a growing body of literature contesting parts of the ovulatory shift hypothesis.
Structural domination in the labor market
Authors: Cicerchia Lillian
Published: May 2019

In recent years, there has been a wide-ranging debate about the neo-republican principle of non-domination. Neo-republicans argue that domination is a capacity for one to intentionally use arbitrary power to interfere in someone’s life. Critics of neo-republicanism argue that this definition of freedom as non-domination precludes a structural analysis of domination, which would explain and critique the ways in which societies produce structural domination unintentionally. The article focuses on capitalism’s labor process and its labor markets. It argues that critics are correct to think that the neo-republican principle of non-domination has an insufficient scope, but that an alternative account of structural domination should still support the neo-republican idea that agency must be involved. Otherwise, we might simply fail to explain the social processes that reproduce structural domination. What is needed is to explain how the labor process creates incentives for agents to intentionally produce structures that have unintended, yet dominating effects, and in turn, how the intentions of agents are conditioned by their social positions. Domination is thus agential and structural.
The Moral Calculus of Vocational Passion in Digital Gaming
Authors: Chia Aleena
Published: May 2019

The desire to “do what you love” energizes employment and engagement in creative industries such as digital gaming yet drains hobbyists and aspirants by normalizing expectations to sacrifice job security for passionate work. This article investigates how individuals regulate their aspirations through taken-for-granted trade-offs between vocational compromise and compensation. Multi-sited ethnographic fieldwork with players at fan conventions and recruitment events in North America suggests a moral calculus of corruption and sublimation between passion and profit, which can be traced back to industrialization’s cleavage of labor from recreation and its institution of hobbies as productive leisure. Building on existing research about waged labor’s imagined denigration of hobbies, this argument juxtaposes the passion that is corruptible by work and the passion that promises to sublimate work from drudgery. Interrogating this confounding logic cultivates counter-narratives for purposeful livelihoods beyond industrial-era notions of productivity and neoliberal notions of passion.
Becoming Gamesworkers: Diversity, Higher Education, and the Future of the Game Industry
Authors: Harvey Alison
Published: May 2019

Higher education qualifications and the training of talent have become increasingly important in game industry and policy discourse in the United Kingdom. This heightened rhetoric and dedicated pots of funding referencing the significance of the games talent pipeline may represent the opportunity to cultivate greater inclusion in the workforce, which continues to be largely homogenous in terms of gender and race. Drawing on qualitative research with stakeholders in five case study institutions, this article highlights the ways in which the production of gamesworker subjectivity by institutions, instructors, and students hinders this possibility. Transparency about the exploitative working conditions and exclusionary norms of the game industry instead becomes the grounds for aggressive and conservative performances of labor bravado, foreclosing collective action, moral arguments about addressing inequalities, and creativity. The article closes by addressing the tension between team-based collaboration and competitive individualism as a site of potential intervention.
Evaluation of the Efficacy of Rotational Corrections for Standard-Fractionation Head and Neck Image-Guided Radiotherapy
Authors: Kung Joseph S. , Tran William T. , Poon Ian , Atenafu Eshetu G. , Courneyea Lorraine , Higgins Kevin , Enepekides Danny , Sahgal Arjun , Chin Lee , Karam Irene
Published: May 2019

Purpose:

Modern linear accelerators are equipped with cone beam computed tomography and robotic couches that can correct for errors in the translational (X, Y, Z) and rotational (α, β, γ) axes prior to treatment delivery. Here, we compared the positional accuracy of 2 cone beam registration approaches: (1) employing translational shifts only in 3 degrees of freedom (X, Y, Z), versus; (2) using translational-rotational shifts in 6 degrees of freedom (X, Y, Z, α, β, γ).

Methods:

This retrospective study examined 140 interfraction cone beam images from 20 patients with head and neck cancer treated with standard intensity-modulated radiation therapy. The cone beam images were matched to planning simulation scans in 3, then in 6 degrees of freedom, using the mandible, clivus, and C2 and C7 vertebrae as surrogate volumes. Statistical analyses included a generalized mixed model and was used to assess whether there were significant differences in acceptable registrations between the 2 correction methods.

Results:

The rates of improvement with corrections in 6 degrees of freedom for the mandible with a 5-mm expansion margin were 54.55% ( P = .793), for the clivus 85.71% ( P = .222), and for C7 87.50% ( P = .015). There was a 100% increase in acceptability for the C2 vertebra within the 5-mm margin ( P < .001). For the 3-mm expansion margin, the rates of improvement for the mandible, clivus, C2, and C7 were 63.16% ( P = .070), 91.30% ( P = .011), 84.21% ( P = .027), and 76.92% ( P < .001), respectively.

Conclusions:

Significant registration improvements with the use of rotational corrections with a 5-mm expansion margin are only seen in the C7 vertebra. At the 3-mm margin, significant improvements are found for the C2, C7, and clivus registrations, suggesting that intensity-modulated radiotherapy treatments for head and neck cancers with 3-mm planning target volume margins may benefit from corrections in 6 degrees of freedom.