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1 – 10 of over 81000Yousef S.H. Najjar and Sharaf F. Al‐Sharif
To develop and find the effect of combination of four cycle design variables that minimizes the specific fuel consumption (sfc) of a turbofan engine.
Abstract
Purpose
To develop and find the effect of combination of four cycle design variables that minimizes the specific fuel consumption (sfc) of a turbofan engine.
Design/methodology/approach
After choosing the four variables, namely bypass ratio (B), fan pressure ratio, overall pressure ratio, and turbine inlet temperature (T04), first the sfc was minimized without a minimum thrust constraint. Then, a minimum specific thrust constraint was introduced.
Findings
The unconstrained‐specific thrust is a two‐dimensional optimization problem, whereas the specific thrust constrained problem was found to be a three‐dimensional one.
Research limitations/implications
The variables B and ï are limiting factors to further improvement, as set by their maximum practical values, whereas the other two variables are to be optimized.
Practical implications
A very useful work, in which numerical optimization program was developed, for a turbofan cycle and could be extended to other cycles.
Originality/value
This paper offers a great help to those intending to optimize certain cycles with a number of variables.
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Feng Yixiong, Gao Yicong, Mai Zeyu and Tan Jianrong
Existing models of product assembly scheme design often ignore the constraint relations among design thinking. In order to grasp the functions of each part and the constraint…
Abstract
Purpose
Existing models of product assembly scheme design often ignore the constraint relations among design thinking. In order to grasp the functions of each part and the constraint relations among them in product assembly system macroscopically, further design and variation of product assembly system should be made according to design thinking. This paper seeks to address these issues.
Design/methodology/approach
Through analyzing the similarity between biological organization system and product system and taking biology knowledge for reference, product assembly system was expressed as product function gene, product constraint gene, product function protein, product constraint protein and product cell and so on in this paper. The product gene model composed of product function gene groups and constraint genes was established and a modeling method based on it was proposed.
Findings
The author applied this method to model the 5‐DOF manipulator of complex diamond manufacturing special equipment with good results which proved the effectiveness of this modeling method.
Originality/value
By identifying constraint relations and design thinking in the gene model, the system makes the modification process which is conducted by the designers automatically identified and varied to achieve computer‐aided design and assembly.
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Alexandra E. MacDougall, Zhanna Bagdasarov, James F. Johnson and Michael D. Mumford
Business ethics provide a potent source of competitive advantage, placing increasing pressure on organizations to create and maintain an ethical workforce. Nonetheless, ethical…
Abstract
Business ethics provide a potent source of competitive advantage, placing increasing pressure on organizations to create and maintain an ethical workforce. Nonetheless, ethical breaches continue to permeate corporate life, suggesting that there is something missing from how we conceptualize and institutionalize organizational ethics. The current effort seeks to fill this void in two ways. First, we introduce an extended ethical framework premised on sensemaking in organizations. Within this framework, we suggest that multiple individual, organizational, and societal factors may differentially influence the ethical sensemaking process. Second, we contend that human resource management plays a central role in sustaining workplace ethics and explore the strategies through which human resource personnel can work to foster an ethical culture and spearhead ethics initiatives. Future research directions applicable to scholars in both the ethics and human resources domains are provided.
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Rex Asibuodu Ugulu, Andrew Arewa and Stephen Allen
The purpose of this paper is to establish the perception of tradespeople about project-specific constraints (PSCs) influencing construction productivity in Nigeria.
Abstract
Purpose
The purpose of this paper is to establish the perception of tradespeople about project-specific constraints (PSCs) influencing construction productivity in Nigeria.
Design/methodology/approach
Using a qualitative descriptive survey comprising face-to-face semi-structured interviews and a purposive sampling method, views of eight groups of tradespeople and seven project managers on live construction projects in Nigeria were collected. The study used conventional content analysis with the aid of NVivo 12 pro computer software for the analysis.
Findings
The research evaluated the PSCs and their effect on construction productivity of tradespeople. The findings identified five key PSCs, namely: lack of promotions/reward system, unsafe/poor health condition of workers, delay in material availability, inadequate site amenities and an ageing workforce. These results support earlier research on constraints influencing labour productivity, however, the poor health condition of workers and material unavailability appear to be more unique when compared to other previous studies.
Research limitations/implications
The study focussed on the Federal Capital Territory Abuja and the Lagos State of Nigeria. It provides insight into the PSCs influencing the productivity of tradespeople in the Nigerian construction industry. Further research to identify the PSCs in depth, in the Eastern part of Nigeria is necessary.
Practical implications
The PSCs influencing tradespeople’s productivity was identified. The level of the relative impact of the PSCs is expected to guide the project team in addressing the PSCs in a method that is cost effective.
Originality/value
This study is original research that has underlined some areas of improvement in construction project performance.
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Tianyu Ying, Jun Wen, Edmund Goh and Shaohua Yang
The relationship between sex and tourism remains ambiguous in the tourism literature. Few studies have examined the underlying motivations behind sex-driven travel, and little is…
Abstract
Purpose
The relationship between sex and tourism remains ambiguous in the tourism literature. Few studies have examined the underlying motivations behind sex-driven travel, and little is known about factors inhibiting tourists' procurement of commercial sex when traveling. Therefore, this study explored male Chinese tourists' perceived constraints during decision-making and developed a comprehensive scale to assess constraints to commercial sex consumption overseas.
Design/methodology/approach
Data were obtained from male Chinese tourists purchasing commercial sex while traveling overseas. This study involved a four-stage process as recommended by Churchill (1979) for scale development research. In Stage 1, preliminary items were generated through a comprehensive review of the constraints literature and in-depth interviews with 16 sex tourists, which generated an initial 26 items. During the second stage to purify the measurement items, six items were eliminated, resulting in 20 items. Stage 3 involved exploratory factor analysis (N = 275) to extract the scale's underlying factor structure. Results revealed a five-factor structure with sufficient evidence of internal reliability given Cronbach's alpha coefficients between 0.722 and 0.843. The final stage included confirmatory factor analysis (N = 259) to verify the scale's reliability and validity.
Findings
Ultimately, 20 items were developed to measure sex tourists' perceived constraints toward engaging in commercial sex services overseas based on five factors: structural constraints, intrapersonal constraints, interpersonal constraints, value conflicts and service supply–related constraints.
Originality/value
This study advances the scope of sex tourism research by verifying how these five constraints are independent, generalized and can influence the procurement of sexual services overseas. This study is the first in sex tourism research to explore the difficulties facing sex tourists. Results offer marketers important insight on how to better address these constraints while providing a safe and legal sex tourism experience.
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This paper aims to develop and validate a framework about the enablers and constraints to the creation, sharing and use of knowledge, by analyzing how enablers and constraints in…
Abstract
Purpose
This paper aims to develop and validate a framework about the enablers and constraints to the creation, sharing and use of knowledge, by analyzing how enablers and constraints in a particular information environment – advocacy networks – impact each of the phases of the knowledge process.
Design/methodology/approach
The setting chosen for this research is a group of leading international non‐governmental organizations (INGOs), and their NGO partners in a developing country, pursuing a policy advocacy strategy in the context of an international donors conference. The qualitative research follows an embedded case study design with two levels of data collection and analysis: intra‐organizational: an individual INGO; and inter‐organizational: the advocacy network to which this INGO belongs.
Findings
Most enablers and constraints are internal to organizations and focus on the phases of knowledge use. Constraints associated with organizations' cultures, individuals' information‐processing preferences, and politics are prominent. The validated framework can then explain how specific constraints influence particular phases of the creation, sharing and use of knowledge and the nature of these constraints in settings where particular organizational cultures dominate.
Originality/value
Researchers have studied the enabling conditions through which knowledge is created and shared. Some contributions have focused on the role of personal beliefs and formal procedures; higher codification of knowledge; social capital; or technology and measurement, among others. The literature has been mainly focused on identifying particular constraints, without paying much attention to how they are manifested in the distinct phases of the knowledge process. This paper aims to make a contribution in this area.
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Yun Zhong Hu, Botao Zhong, Hanbin Luo and Hai Meng Hu
The purpose of this paper is to explore the feasibility that an ontological approach can be applied to formalize the construction regulation constraint knowledge in a…
Abstract
Purpose
The purpose of this paper is to explore the feasibility that an ontological approach can be applied to formalize the construction regulation constraint knowledge in a computer-interpretable way, for construction quality checking, during construction stage.
Design/methodology/approach
The ontological and semantic web technologies are used to model the construction quality constraints knowledge into Axioms/OWL and SWRL rules. Protégé platform is selected to illustrate how the construction quality checking, based on the Axioms/OWL and SWRL rules, is achieved.
Findings
The ontology and semantic web technologies can be an alternative way for modeling the construction regulation constraints in a computer-interpretable way, and can be implemented for the regulation-based construction quality checking.
Research limitations/implications
The approach is illustrated only with given specific technical constraints examples, the generality and practicality of the approach need further investigation.
Originality/value
The paper introduces an ontological and semantic approach to model and formalize the construction regulation constraints for construction quality checking, and proves the feasibility by the case studies. The proposed approach enables the regulations can be understood and retrieved semantically by computers, which facilitates the using of regulation codes.
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Marwa Khalfalli, Fouad Ben Abdelaziz and Hichem Kamoun
The purpose of this paper is to generate a daily operating theater schedule aiming to minimize completion time and maximum overtime while integrating real-life surgeon constraints…
Abstract
Purpose
The purpose of this paper is to generate a daily operating theater schedule aiming to minimize completion time and maximum overtime while integrating real-life surgeon constraints, such as their role, specialty, qualification and availability.
Design/methodology/approach
The paper deals with complete surgery process using multi-objective surgery scheduling approach. Furthermore, the combinatorial nature of the studied problem does not allow to solve it to optimality. Therefore, the authors developed two approaches embedded in a tabu search metaheuristic, namely, weighted sum and e-constraint, to minimize completion time and maximum overtime.
Findings
The integration of the upstream and downstream services of an intervention and the consideration of the specific constraints related to surgeons are very essential to obtaining more closed schedules to the realty.
Practical implications
The paper includes implications for the development of efficient schedules for a significant number of operations coming from different specialties throughout its complete surgery process under multi-resource constraints.
Social implications
The paper can help hospital managers and decision makers to well manage the budget by minimizing the overtime cost and by offering efficient daily operating theater schedule.
Originality/value
The results of the paper will help hospital managers and decision makers to well manage the budget by minimizing the overtime cost and offering efficient daily operating theater schedule.
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This chapter presents application of multi-criteria mathematical programming models by integer and mixed-integer programming for optimal allocation of workers among supporting…
Abstract
This chapter presents application of multi-criteria mathematical programming models by integer and mixed-integer programming for optimal allocation of workers among supporting services in a hospital. The services include logistics, inventory management, financial management, operations management, medical analysis, etc. The optimality criteria of the problem are minimization of operational costs of supporting services subject to some specific constraints. The constraints represent specific conditions for resource allocation in a hospital. The overall problems are formulated as assignment models, where the decision variables represent the assignment of people to various jobs. Numerical examples are presented. Some computational results modeled on a real data from a hospital in Poland are reported.
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Roda Müller-Wieland, Antonia Muschner and Martina Schraudner
Academic entrepreneurship is extremely relevant in knowledge and technology transfer (KTT). The purpose of this study is to provide insights into phase-specific constraints and…
Abstract
Purpose
Academic entrepreneurship is extremely relevant in knowledge and technology transfer (KTT). The purpose of this study is to provide insights into phase-specific constraints and needs impacting scientists’ engagement in entrepreneurial activities at public research institutions.
Design/methodology/approach
In an exploratory case study, 40 qualitative, semi-structured interviews were conducted with German academic entrepreneurs in the fields of science, technology, engineering and mathematics (STEM).
Findings
Based on the data analysis, an ideal-typical founding process with phase-specific barriers and needs was identified. Many constraints and associated needs occur in more than one phase, including the lack of knowledge, the demand for exchange formats, the lack of time and financial resources, institutionalized return options, the lack of human resources and the lack of incentives.
Research limitations/implications
Given its exploratory approach, this study has limitations regarding its generalization; however, the presented findings may induce further research and in-depth analysis on this matter.
Practical implications
Several recommendations for action are provided for each phase of the founding process to strengthen the (entrepreneurial) transfer in research organizations. Generally, a pioneering indicator of excellence in the science system should be developed to promote transfer next to publications.
Originality/value
The study contributes to existing literature on determinants of academic entrepreneurship by indicating the phase-specific constraints and needs throughout the founding process and discussing those needs in the theoretical context of current societal and technological mega-trends.
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