A pseudo steady‐state model is developed to study heat transfer, fluidflow, and the interface shape in the liquid encapsulated vertical Bridgmancrystal growth. The model, which is…
Abstract
A pseudo steady‐state model is developed to study heat transfer, fluid flow, and the interface shape in the liquid encapsulated vertical Bridgman crystal growth. The model, which is governed by momentum, heat, and overall mass balances in the system, is solved by a finite‐volume/Newton method. Flow and temperature fields, as well as unknown melt/crystal and melt/encapsulant interfaces, are calculated simultaneously. Sample calculations are mainly conducted for the GaAs/B2O3/PBN system. Calculated results for the Germanium/graphite system are compared with finite element calculations by Adornato and Brown, and they are in good agreement. The effects of some process parameters, including the growth speed, ambient temperature profile and heat transfer conditions, on flow patterns, temperature fields and the interface shape are illustrated through calculated results. Interface inversion from concave to convex, by modifying the ambient temperature profile, is also demonstrated through computer simulation. Particularly, through an inverse problem approach, a flat interface can be easily obtained for various operation conditions.
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Yasunori Okano, Susumu Sakai, Takahiro Morita and Jun Shimizu
A finite difference simulation for the bulk single crystal growth of indium phosphide by the liquid encapsulated vertical gradient freezing (LE‐VGF) method with a flat bottom…
Abstract
A finite difference simulation for the bulk single crystal growth of indium phosphide by the liquid encapsulated vertical gradient freezing (LE‐VGF) method with a flat bottom crucible is presented. In order to treat a curvature interface, the boundary fixing method is applied. The transient behavior of the flow and temperature fields, the melt/crystal interface shape and the growth rate during growth are studied numerically. The crystal growth rate is not constant although the temperature lowering rate is constant. The effect of crucible thickness, thermal conductivity of the crucible and temperature of the growth furnace wall on the crystal growth behavior are discussed.
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Qingfeng Chen, Zhe Zhao, Wei Lan, Ruchang Zhang and Jiahai Liang
MicroRNAs (miRNAs) have been proved to be a significant type of non-coding RNAs related to various human diseases. This paper aims to identify the potential miRNA–disease…
Abstract
Purpose
MicroRNAs (miRNAs) have been proved to be a significant type of non-coding RNAs related to various human diseases. This paper aims to identify the potential miRNA–disease interactions.
Design/methodology/approach
A computational framework, MDIRM is presented to predict miRNAs-disease interactions. Unlike traditional approaches, the miRNA function similarity is calculated by miRNA–disease interactions. The k-mean method is further used to cluster miRNA similarity network. For miRNAs in the same cluster, their similarities are enhanced, as the miRNAs from the same cluster may be reliable. Further, the potential miRNA–disease association is predicted by using recommend method.
Findings
To evaluate the performance of our model, the fivefold cross validation is implemented to compare with two state-of-the-art methods. The experimental results indicate that MDIRM achieves an AUC of 0.926, which outperforms other methods.
Originality/value
This paper proposes a novel computational method for miRNA–disease interaction prediction based on recommend method. Identifying the relationship between miRNAs and diseases not only helps us better understand the disease occurrence and mechanism through the perspective of miRNA but also promotes disease diagnosis and treatment.
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Barbados is at a very advanced stage of population aging. Health care services are designed to ensure universal access for all Barbadians but the contributing factors for older…
Abstract
Purpose
Barbados is at a very advanced stage of population aging. Health care services are designed to ensure universal access for all Barbadians but the contributing factors for older adults’ health care utilization are not well explored. This chapter examines gender differences in the correlates of seeking medical care among older adults in Barbados.
Methodology/approach
Logistic regression models were applied to data drawn from the 2000 Survey of Health, Well-Being and Aging of Older Adults in Latin America and the Caribbean (SABE), Bridgetown sample (n = 1,068).
Findings
Health needs, based on chronic conditions, were positively associated with seeking medical care for men and women. Different forms and directions of intergenerational support were associated with men and women seeking care. Among men, receiving financial support was positively associated with seeking care. Among women, providing financial support was associated with lower odds of seeking care while receiving instrumental support was associated with higher odds of seeking care.
Research limitations/implications
Medical care is only one form of health care use and there is no specification of the nature of care or consultation. The sample is cross-sectional and limited to older adults in urban areas. The relative importance of enabling factors and health needs, especially, may differ across time and space within Barbados.
Originality/value
The study contributes to the literature on health care utilization among older adults within developing countries and highlights the pertinence of family relations influencing gender differences in health care utilization.
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Wei‐Wen Wu, Lawrence W. Lan and Yu‐Ting Lee
The purpose of this paper is to propose a benchmarking framework to evaluate the efficiency and effectiveness of the hotel industry, in a multi‐period context, with consideration…
Abstract
Purpose
The purpose of this paper is to propose a benchmarking framework to evaluate the efficiency and effectiveness of the hotel industry, in a multi‐period context, with consideration of perishable traits and carry‐over activities. The sustained high performers in the case study are identified and their business strategies are discussed.
Design/methodology/approach
The dynamic DEA (data envelopment analysis) approach is used to identify the multi‐period sustained high performers. The super‐efficiency DEA approach is employed to conduct a thorough ranking under an input‐output‐consumption structure. The supplementary analysis is further implemented to help elucidate the benchmarking results.
Findings
In total, nine out of 80 international tourist hotels in Taiwan during 2006‐2010 are identified as the sustained high performers. These hotels have diverged business strategies in terms of employees (intensive versus economical labor forces), products (room versus F&B (food and beverage) services), prices (extremely expensive versus very inexpensive room rates), guests (business versus tourism guests), and others (e.g. location advantages).
Originality/value
This study contributes to benchmarking literature and to hotel industry in several aspects. Compared with conventional single‐period benchmarking in efficiency aspect only, the proposed multi‐period benchmarking framework under input‐production‐consumption structure can take into account the carry‐over activities, account for perishable traits, provide more robust results, and add more useful information to facilitate the hotel managers to ameliorate the efficiency and effectiveness. The proposed framework should be readily applied to other service industries (e.g. transport).
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Hussein Bazzi, Cong Tam Nguyen and Nicolas Galanis
This work is concerned with the problem of the transient behaviours of the axisymmetric thermocapillary laminar flow occurring inside a half zone subjected to a variable thermal…
Abstract
This work is concerned with the problem of the transient behaviours of the axisymmetric thermocapillary laminar flow occurring inside a half zone subjected to a variable thermal boundary condition during a heating process. The molten liquid with its deformable free surface is considered incompressible with constant physical properties except for its density in buoyancy forces where Boussinesq’s approximation has been applied. The system of governing equations has been successfully solved by using the modified‐SIMPLE method, while the instantaneous position of the free surface was determined by employing a special procedure. Numerical simulations have been carried out for both NaNO3 and Silicon float zones operating under 1‐g and μ‐g conditions. The transient behaviours as well as the influence of the Marangoni number and the aspect ratio have been investigated.
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Alireza Moradi, Saber Saati and Mehrzad Navabakhsh
Many researchers and analysts are interested in evaluating the performance of a system with a network structure as a decision-making unit. In this regard, fuzzy network data…
Abstract
Purpose
Many researchers and analysts are interested in evaluating the performance of a system with a network structure as a decision-making unit. In this regard, fuzzy network data envelopment analysis (FNDEA) is a noticeable and worthy method for evaluating the efficiency of a system with fuzzy data. Based on the structure of a fuzzy network system, which consists of at least two serial stages, an intermediate factor has an output nature for the first stage and an input nature for the second stage. Hence, it is inappropriate to allocate the same weight for each stage using this factor. Unfortunately, contrary to real-world conditions, all previous conventional FNDEA studies have considered the same role for intermediate factors to linearize or simplify models. For the first time, this study attempts to determine the upper and lower bounds of the overall efficiencies of a fuzzy two-stage series system and its subprocesses with unequal intermediate product weights.
Design/methodology/approach
The proposed model remains in its original nature as a complex combinatorial problem in the nonlinear programming category of NP-hard problems. A genetic algorithm (GA) is utilized as a metaheuristic algorithm, and a novel hybrid GA-FNDEA algorithm is presented to solve the problem.
Findings
The findings of the study outlined several theoretical contributions and practical implications, including as compensatory property of DEA, determining upper and lower bounds, improving efficiency in nonlinear systems, reducing computational burden, enhancing evolutionary algorithms and retaining real-world conditions.
Originality/value
Contrary to real-world conditions, all previous conventional FNDEA studies have considered the same role for intermediate factors to linearize or simplify models. For the first time, this study attempts to determine the upper and lower bounds of the overall efficiencies of a fuzzy two-stage series system and its subprocesses with unequal intermediate product weights.
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Fuad Sameh Alshraiedeh and Norliza Katuk
Many REpresentational State Transfer (RESTful) Web services suffered from anti-patterns problem, which may diminish the sustainability of the services. The anti-patterns problem…
Abstract
Purpose
Many REpresentational State Transfer (RESTful) Web services suffered from anti-patterns problem, which may diminish the sustainability of the services. The anti-patterns problem could happen in the code of the programme or the uniform resource identifiers (URIs) of RESTful Web services. This study aims to address the problem by proposing a technique and an algorithm for detecting anti-patterns in RESTful Web services. Specifically, the technique is designed based on URIs parsing process.
Design/methodology/approach
The study was conducted following the design science research process, which has six activities, namely, identifying problems, identifying solutions, design the solutions, demonstrate the solution, evaluation and communicate the solution. The proposed technique was embedded in an algorithm and evaluated in four phases covering the process of extracting the URIs, implementing the anti-pattern detection algorithm, detecting the anti-patterns and validating the results.
Findings
The results of the study suggested an acceptable level of accuracy for the anti-patterns detection with 82.30% of precision, 87.86% of recall and 84.93% of F-measure.
Practical implications
The technique and the algorithm can be used by developers of RESTful Web services to detect possible anti-pattern occurrences in the service-based systems.
Originality/value
The technique is personalised to detect amorphous URI and ambiguous name anti-patterns in which it scans the Web service URIs using specified rules and compares them with pre-determined syntax and corpus.
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Hakan F. Oztop, Kolsi Lioua, Borjini Mohamad Naceur and Khaled Al-Salem
The main purpose of this paper is to conduct on three-dimensional buoyancy and thermocapillary convection in an enclosure. Entropy generation is obtained from the calculated…
Abstract
Purpose
The main purpose of this paper is to conduct on three-dimensional buoyancy and thermocapillary convection in an enclosure. Entropy generation is obtained from the calculated values of velocities and temperatures.
Design/methodology/approach
As numerical method, the vorticity-vector potential formalism allows, in a three-dimensional configuration, the elimination of the pressure, which is a delicate term to treat. The control volume finite difference method is used to discretize equations. The central-difference scheme for treating convective terms and the fully implicit procedure to discretize the temporal derivatives are retained. The grid is uniform in all directions with additional nodes on boundaries. The successive relaxation iterating scheme is used to solve the resulting non-linear algebraic equations.
Findings
Results are presented via entropy generation due to heat transfer, entropy generation due to fluid friction and total entropy generation. It is found that Marangoni number becomes more effective parameter on total entropy generation for lower values of Rayleigh numbers.
Practical implications
In any thermal system under buoyancy induced and thermocapillary flow.
Originality/value
It is believed that this is the first paper on three-dimensional solution of entropy generation in a cubical cavity under thermocapillary buoyancy flow.
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Lamia Haque and Robert Rosenheck
While many studies have shown that liver diseases (LD) can be caused or exacerbated by substance use disorders (SUD), few have examined the proportion of adults with LD and SUD…
Abstract
Purpose
While many studies have shown that liver diseases (LD) can be caused or exacerbated by substance use disorders (SUD), few have examined the proportion of adults with LD and SUD who receive mental health and addiction treatment or correlates of such use.
Design/methodology/approach
Using national Fiscal Year (FY) 2012 data from the United States Veterans Health Administration (VHA), the authors studied all 43,246 veterans diagnosed with both LD and SUD in FY 2012 and compared those who received mental health treatment (n = 30,456; 70.4%) to those who did not (n = 12,790; 29.6%).
Findings
Veterans who received mental health treatment were less like to be older than 75 years of age, more likely to have served during recent Middle East conflicts (Operation Iraqi Freedom or Operation Enduring Freedom), more likely to have been recently homeless and to have drug dependence as contrasted with alcohol dependence when compared with those who did not receive mental health treatment. Although the majority, 70.4%, received mental health treatment, only 30.6% of the total received specialized addiction treatment, and these veterans were more likely to experience homelessness and have drug dependence diagnoses.
Originality/value
This is the first study as per the authors’ best knowledge that broadly examines mental health and addiction treatment received by veterans with LD and SUD. High rates of mental health treatment in this population likely reflect the integrated nature of the VHA and its emphasis on providing comprehensive services to homeless veterans. Further research is needed to identify barriers to specialized addiction treatment in this population.